coreos-cloudinit: bump to 0.9.0

Logs

Documentation/cloud-config-oem.md

@@ -13,7 +13,7 @@ If no **id** field is provided, coreos-cloudinit will ignore this section.
 
 For example, the following cloud-config document...
 
-```
+```yaml
 #cloud-config
 coreos:
   oem:
@@ -26,7 +26,7 @@ coreos:
 
 ...would be rendered to the following `/etc/oem-release`:
 
-```
+```yaml
 ID=rackspace
 NAME="Rackspace Cloud Servers"
 VERSION_ID=168.0.0

Documentation/cloud-config.md

@@ -16,7 +16,7 @@ We've designed our implementation to allow the same cloud-config file to work ac
 
 The cloud-config file uses the [YAML][yaml] file format, which uses whitespace and new-lines to delimit lists, associative arrays, and values.
 
-A cloud-config file should contain an associative array which has zero or more of the following keys:
+A cloud-config file should contain `#cloud-config`, followed by an associative array which has zero or more of the following keys:
 
 - `coreos`
 - `ssh_authorized_keys`
@@ -42,7 +42,7 @@ CoreOS tries to conform to each platform's native method to provide user data. E
 The `coreos.etcd.*` parameters will be translated to a partial systemd unit acting as an etcd configuration file.
 We can use the templating feature of coreos-cloudinit to automate etcd configuration with the `$private_ipv4` and `$public_ipv4` fields. For example, the following cloud-config document...
 
-```
+```yaml
 #cloud-config
 
 coreos:
@@ -57,7 +57,7 @@ coreos:
 
 ...will generate a systemd unit drop-in like this:
 
-```
+```yaml
 [Service]
 Environment="ETCD_NAME=node001"
 Environment="ETCD_DISCOVERY=https://discovery.etcd.io/<token>"
@@ -74,7 +74,7 @@ Note that hyphens in the coreos.etcd.* keys are mapped to underscores.
 
 The `coreos.fleet.*` parameters work very similarly to `coreos.etcd.*`, and allow for the configuration of fleet through environment variables. For example, the following cloud-config document...
 
-```
+```yaml
 #cloud-config
 
 coreos:
@@ -85,7 +85,7 @@ coreos:
 
 ...will generate a systemd unit drop-in like this:
 
-```
+```yaml
 [Service]
 Environment="FLEET_PUBLIC_IP=203.0.113.29"
 Environment="FLEET_METADATA=region=us-west"
@@ -114,7 +114,7 @@ The `reboot-strategy` parameter also affects the behaviour of [locksmith](https:
 
 ##### Example
 
-```
+```yaml
 #cloud-config
 coreos:
   update:
@@ -138,7 +138,7 @@ The `coreos.units.*` parameters define a list of arbitrary systemd units to star
 
 Write a unit to disk, automatically starting it.
 
-```
+```yaml
 #cloud-config
 
 coreos:
@@ -159,7 +159,7 @@ coreos:
 
 Start the built-in `etcd` and `fleet` services:
 
-```
+```yaml
 #cloud-config
 
 coreos:
@@ -177,7 +177,7 @@ The `ssh_authorized_keys` parameter adds public SSH keys which will be authorize
 The keys will be named "coreos-cloudinit" by default.
 Override this by using the `--ssh-key-name` flag when calling `coreos-cloudinit`.
 
-```
+```yaml
 #cloud-config
 
 ssh_authorized_keys:
@@ -189,7 +189,7 @@ ssh_authorized_keys:
 The `hostname` parameter defines the system's hostname.
 This is the local part of a fully-qualified domain name (i.e. `foo` in `foo.example.com`).
 
-```
+```yaml
 #cloud-config
 
 hostname: coreos1
@@ -222,7 +222,7 @@ The following fields are not yet implemented:
 - **selinux-user**: Corresponding SELinux user
 - **ssh-import-id**: Import SSH keys by ID from Launchpad.
 
-```
+```yaml
 #cloud-config
 
 users:
@@ -261,7 +261,7 @@ Using a higher number of rounds will help create more secure passwords, but give
 
 Using the `coreos-ssh-import-github` field, we can import public SSH keys from a GitHub user to use as authorized keys to a server.
 
-```
+```yaml
 #cloud-config
 
 users:
@@ -274,7 +274,7 @@ users:
 We can also pull public SSH keys from any HTTP endpoint which matches [GitHub's API response format](https://developer.github.com/v3/users/keys/#list-public-keys-for-a-user).
 For example, if you have an installation of GitHub Enterprise, you can provide a complete URL with an authentication token:
 
-```
+```yaml
 #cloud-config
 
 users:
@@ -284,7 +284,7 @@ users:
 
 You can also specify any URL whose response matches the JSON format for public keys:
 
-```
+```yaml
 #cloud-config
 
 users:
@@ -304,7 +304,7 @@ The `write-file` parameter defines a list of files to create on the local filesy
 Explicitly not implemented is the **encoding** attribute.
 The **content** field must represent exactly what should be written to disk.
 
-```
+```yaml
 #cloud-config
 write_files:
   - path: /etc/fleet/fleet.conf
@@ -321,7 +321,7 @@ Currently, the only supported value is "localhost" which will cause your system'
 to resolve to "127.0.0.1".  This is helpful when the host does not have DNS
 infrastructure in place to resolve its own hostname, for example, when using Vagrant.
 
-```
+```yaml
 #cloud-config
 
 manage_etc_hosts: localhost

Documentation/config-drive.md

@@ -14,17 +14,21 @@ The image should be a single FAT or ISO9660 file system with the label
 
 For example, to wrap up a config named `user_data` in a config drive image:
 
-    mkdir -p /tmp/new-drive/openstack/latest
-    cp user_data /tmp/new-drive/openstack/latest/user_data
-    mkisofs -R -V config-2 -o configdrive.iso /tmp/new-drive
-    rm -r /tmp/new-drive
+```sh
+mkdir -p /tmp/new-drive/openstack/latest
+cp user_data /tmp/new-drive/openstack/latest/user_data
+mkisofs -R -V config-2 -o configdrive.iso /tmp/new-drive
+rm -r /tmp/new-drive
+```
 
 ## QEMU virtfs
 
 One exception to the above, when using QEMU it is possible to skip creating an
 image and use a plain directory containing the same contents:
 
-    qemu-system-x86_64 \
+```sh
+qemu-system-x86_64 \
     -fsdev local,id=conf,security_model=none,readonly,path=/tmp/new-drive \
     -device virtio-9p-pci,fsdev=conf,mount_tag=config-2 \
     [usual qemu options here...]
+```

Documentation/debian-interfaces.md

@@ -0,0 +1,27 @@
+#Debian Interfaces#
+**WARNING**: This option is EXPERIMENTAL and may change or be removed at any
+point.  
+There is basic support for converting from a Debian network configuration to
+networkd unit files. The -convert-netconf=debian option is used to activate
+this feature.
+
+#convert-netconf#
+Default: ""  
+Read the network config provided in cloud-drive and translate it from the
+specified format into networkd unit files (requires the -from-configdrive
+flag). Currently only supports "debian" which provides support for a small
+subset of the [Debian network configuration]
+(https://wiki.debian.org/NetworkConfiguration). These options include:
+
+- interface config methods
+	- static
+		- address/netmask
+		- gateway
+		- hwaddress
+		- dns-nameservers
+	- dhcp
+		- hwaddress
+	- manual
+	- loopback
+- vlan_raw_device
+- bond-slaves

coreos-cloudinit.go

@@ -1,71 +1,69 @@
 package main
 
 import (
-	"encoding/json"
 	"flag"
 	"fmt"
-	"io/ioutil"
 	"os"
-	"path"
+	"sync"
+	"time"
 
 	"github.com/coreos/coreos-cloudinit/datasource"
 	"github.com/coreos/coreos-cloudinit/initialize"
-	"github.com/coreos/coreos-cloudinit/network"
+	"github.com/coreos/coreos-cloudinit/pkg"
 	"github.com/coreos/coreos-cloudinit/system"
 )
 
-const version = "0.7.7"
+const (
+	version               = "0.9.0"
+	datasourceInterval    = 100 * time.Millisecond
+	datasourceMaxInterval = 30 * time.Second
+	datasourceTimeout     = 5 * time.Minute
+)
+
+var (
+	printVersion  bool
+	ignoreFailure bool
+	sources       struct {
+		file            string
+		configDrive     string
+		metadataService bool
+		url             string
+		procCmdLine     bool
+	}
+	convertNetconf string
+	workspace      string
+	sshKeyName     string
+)
+
+func init() {
+	flag.BoolVar(&printVersion, "version", false, "Print the version and exit")
+	flag.BoolVar(&ignoreFailure, "ignore-failure", false, "Exits with 0 status in the event of malformed input from user-data")
+	flag.StringVar(&sources.file, "from-file", "", "Read user-data from provided file")
+	flag.StringVar(&sources.configDrive, "from-configdrive", "", "Read data from provided cloud-drive directory")
+	flag.BoolVar(&sources.metadataService, "from-metadata-service", false, "Download data from metadata service")
+	flag.StringVar(&sources.url, "from-url", "", "Download user-data from provided url")
+	flag.BoolVar(&sources.procCmdLine, "from-proc-cmdline", false, fmt.Sprintf("Parse %s for '%s=<url>', using the cloud-config served by an HTTP GET to <url>", datasource.ProcCmdlineLocation, datasource.ProcCmdlineCloudConfigFlag))
+	flag.StringVar(&convertNetconf, "convert-netconf", "", "Read the network config provided in cloud-drive and translate it from the specified format into networkd unit files (requires the -from-configdrive flag)")
+	flag.StringVar(&workspace, "workspace", "/var/lib/coreos-cloudinit", "Base directory coreos-cloudinit should use to store data")
+	flag.StringVar(&sshKeyName, "ssh-key-name", initialize.DefaultSSHKeyName, "Add SSH keys to the system with the given name")
+}
 
 func main() {
-	var printVersion bool
-	flag.BoolVar(&printVersion, "version", false, "Print the version and exit")
-
-	var ignoreFailure bool
-	flag.BoolVar(&ignoreFailure, "ignore-failure", false, "Exits with 0 status in the event of malformed input from user-data")
-
-	var file string
-	flag.StringVar(&file, "from-file", "", "Read user-data from provided file")
-
-	var configdrive string
-	flag.StringVar(&configdrive, "from-configdrive", "", "Read user-data from provided cloud-drive directory")
-
-	var url string
-	flag.StringVar(&url, "from-url", "", "Download user-data from provided url")
-
-	var useProcCmdline bool
-	flag.BoolVar(&useProcCmdline, "from-proc-cmdline", false, fmt.Sprintf("Parse %s for '%s=<url>', using the cloud-config served by an HTTP GET to <url>", datasource.ProcCmdlineLocation, datasource.ProcCmdlineCloudConfigFlag))
-
-	var convertNetconf string
-	flag.StringVar(&convertNetconf, "convert-netconf", "", "Read the network config provided in cloud-drive and translate it from the specified format into networkd unit files (requires the -from-configdrive flag)")
-
-	var workspace string
-	flag.StringVar(&workspace, "workspace", "/var/lib/coreos-cloudinit", "Base directory coreos-cloudinit should use to store data")
-
-	var sshKeyName string
-	flag.StringVar(&sshKeyName, "ssh-key-name", initialize.DefaultSSHKeyName, "Add SSH keys to the system with the given name")
-
 	flag.Parse()
 
+	die := func() {
+		if ignoreFailure {
+			os.Exit(0)
+		}
+		os.Exit(1)
+	}
+
 	if printVersion == true {
 		fmt.Printf("coreos-cloudinit version %s\n", version)
 		os.Exit(0)
 	}
 
-	var ds datasource.Datasource
-	if file != "" {
-		ds = datasource.NewLocalFile(file)
-	} else if url != "" {
-		ds = datasource.NewMetadataService(url)
-	} else if configdrive != "" {
-		ds = datasource.NewConfigDrive(configdrive)
-	} else if useProcCmdline {
-		ds = datasource.NewProcCmdline()
-	} else {
-		fmt.Println("Provide one of --from-file, --from-configdrive, --from-url or --from-proc-cmdline")
-		os.Exit(1)
-	}
-
-	if convertNetconf != "" && configdrive == "" {
+	if convertNetconf != "" && sources.configDrive == "" {
 		fmt.Println("-convert-netconf flag requires -from-configdrive")
 		os.Exit(1)
 	}
@@ -78,111 +76,206 @@ func main() {
 		os.Exit(1)
 	}
 
+	dss := getDatasources()
+	if len(dss) == 0 {
+		fmt.Println("Provide at least one of --from-file, --from-configdrive, --from-metadata-service, --from-url or --from-proc-cmdline")
+		os.Exit(1)
+	}
+
+	ds := selectDatasource(dss)
+	if ds == nil {
+		fmt.Println("No datasources available in time")
+		die()
+	}
+
 	fmt.Printf("Fetching user-data from datasource of type %q\n", ds.Type())
-	userdataBytes, err := ds.Fetch()
+	userdataBytes, err := ds.FetchUserdata()
 	if err != nil {
 		fmt.Printf("Failed fetching user-data from datasource: %v\n", err)
-		if ignoreFailure {
-			os.Exit(0)
-		} else {
-			os.Exit(1)
+		die()
+	}
+
+	fmt.Printf("Fetching meta-data from datasource of type %q\n", ds.Type())
+	metadataBytes, err := ds.FetchMetadata()
+	if err != nil {
+		fmt.Printf("Failed fetching meta-data from datasource: %v\n", err)
+		die()
+	}
+
+	// Extract IPv4 addresses from metadata if possible
+	var subs map[string]string
+	if len(metadataBytes) > 0 {
+		subs, err = initialize.ExtractIPsFromMetadata(metadataBytes)
+		if err != nil {
+			fmt.Printf("Failed extracting IPs from meta-data: %v\n", err)
+			die()
 		}
 	}
 
-	env := initialize.NewEnvironment("/", workspace)
-	if len(userdataBytes) > 0 {
-		if err := processUserdata(string(userdataBytes), env); err != nil {
-			fmt.Printf("Failed resolving user-data: %v\n", err)
-			if !ignoreFailure {
-				os.Exit(1)
-			}
+	// Apply environment to user-data
+	env := initialize.NewEnvironment("/", ds.ConfigRoot(), workspace, convertNetconf, sshKeyName, subs)
+	userdata := env.Apply(string(userdataBytes))
+
+	var ccm, ccu *initialize.CloudConfig
+	var script *system.Script
+	if ccm, err = initialize.ParseMetaData(string(metadataBytes)); err != nil {
+		fmt.Printf("Failed to parse meta-data: %v\n", err)
+		die()
 	}
+	if ud, err := initialize.ParseUserData(userdata); err != nil {
+		fmt.Printf("Failed to parse user-data: %v\n", err)
+		die()
 	} else {
-		fmt.Println("No user data to handle.")
+		switch t := ud.(type) {
+		case *initialize.CloudConfig:
+			ccu = t
+		case system.Script:
+			script = &t
+		}
 	}
 
-	if convertNetconf != "" {
-		if err := processNetconf(convertNetconf, configdrive); err != nil {
-			fmt.Printf("Failed to process network config: %v\n", err)
-			if !ignoreFailure {
-				os.Exit(1)
+	var cc *initialize.CloudConfig
+	if ccm != nil && ccu != nil {
+		fmt.Println("Merging cloud-config from meta-data and user-data")
+		merged := mergeCloudConfig(*ccm, *ccu)
+		cc = &merged
+	} else if ccm != nil && ccu == nil {
+		fmt.Println("Processing cloud-config from meta-data")
+		cc = ccm
+	} else if ccm == nil && ccu != nil {
+		fmt.Println("Processing cloud-config from user-data")
+		cc = ccu
+	} else {
+		fmt.Println("No cloud-config data to handle.")
 	}
+
+	if cc != nil {
+		if err = initialize.Apply(*cc, env); err != nil {
+			fmt.Printf("Failed to apply cloud-config: %v\n", err)
+			die()
+		}
+	}
+
+	if script != nil {
+		if err = runScript(*script, env); err != nil {
+			fmt.Printf("Failed to run script: %v\n", err)
+			die()
 		}
 	}
 }
 
-func processUserdata(userdata string, env *initialize.Environment) error {
-	userdata = env.Apply(userdata)
-
-	parsed, err := initialize.ParseUserData(userdata)
-	if err != nil {
-		fmt.Printf("Failed parsing user-data: %v\n", err)
-		return err
+// mergeCloudConfig merges certain options from mdcc (a CloudConfig derived from
+// meta-data) onto udcc (a CloudConfig derived from user-data), if they are
+// not already set on udcc (i.e. user-data always takes precedence)
+// NB: This needs to be kept in sync with ParseMetadata so that it tracks all
+// elements of a CloudConfig which that function can populate.
+func mergeCloudConfig(mdcc, udcc initialize.CloudConfig) (cc initialize.CloudConfig) {
+	if mdcc.Hostname != "" {
+		if udcc.Hostname != "" {
+			fmt.Printf("Warning: user-data hostname (%s) overrides metadata hostname (%s)", udcc.Hostname, mdcc.Hostname)
+		} else {
+			udcc.Hostname = mdcc.Hostname
 		}
 
-	err = initialize.PrepWorkspace(env.Workspace())
+	}
+	for _, key := range mdcc.SSHAuthorizedKeys {
+		udcc.SSHAuthorizedKeys = append(udcc.SSHAuthorizedKeys, key)
+	}
+	if mdcc.NetworkConfigPath != "" {
+		if udcc.NetworkConfigPath != "" {
+			fmt.Printf("Warning: user-data NetworkConfigPath %s overrides metadata NetworkConfigPath %s", udcc.NetworkConfigPath, mdcc.NetworkConfigPath)
+		} else {
+			udcc.NetworkConfigPath = mdcc.NetworkConfigPath
+		}
+	}
+	return udcc
+}
+
+// getDatasources creates a slice of possible Datasources for cloudinit based
+// on the different source command-line flags.
+func getDatasources() []datasource.Datasource {
+	dss := make([]datasource.Datasource, 0, 5)
+	if sources.file != "" {
+		dss = append(dss, datasource.NewLocalFile(sources.file))
+	}
+	if sources.url != "" {
+		dss = append(dss, datasource.NewRemoteFile(sources.url))
+	}
+	if sources.configDrive != "" {
+		dss = append(dss, datasource.NewConfigDrive(sources.configDrive))
+	}
+	if sources.metadataService {
+		dss = append(dss, datasource.NewMetadataService())
+	}
+	if sources.procCmdLine {
+		dss = append(dss, datasource.NewProcCmdline())
+	}
+	return dss
+}
+
+// selectDatasource attempts to choose a valid Datasource to use based on its
+// current availability. The first Datasource to report to be available is
+// returned. Datasources will be retried if possible if they are not
+// immediately available. If all Datasources are permanently unavailable or
+// datasourceTimeout is reached before one becomes available, nil is returned.
+func selectDatasource(sources []datasource.Datasource) datasource.Datasource {
+	ds := make(chan datasource.Datasource)
+	stop := make(chan struct{})
+	var wg sync.WaitGroup
+
+	for _, s := range sources {
+		wg.Add(1)
+		go func(s datasource.Datasource) {
+			defer wg.Done()
+
+			duration := datasourceInterval
+			for {
+				fmt.Printf("Checking availability of %q\n", s.Type())
+				if s.IsAvailable() {
+					ds <- s
+					return
+				} else if !s.AvailabilityChanges() {
+					return
+				}
+				select {
+				case <-stop:
+					return
+				case <-time.Tick(duration):
+					duration = pkg.ExpBackoff(duration, datasourceMaxInterval)
+				}
+			}
+		}(s)
+	}
+
+	done := make(chan struct{})
+	go func() {
+		wg.Wait()
+		close(done)
+	}()
+
+	var s datasource.Datasource
+	select {
+	case s = <-ds:
+	case <-done:
+	case <-time.Tick(datasourceTimeout):
+	}
+
+	close(stop)
+	return s
+}
+
+// TODO(jonboulle): this should probably be refactored and moved into a different module
+func runScript(script system.Script, env *initialize.Environment) error {
+	err := initialize.PrepWorkspace(env.Workspace())
 	if err != nil {
 		fmt.Printf("Failed preparing workspace: %v\n", err)
 		return err
 	}
-
-	switch t := parsed.(type) {
-	case initialize.CloudConfig:
-		err = initialize.Apply(t, env)
-	case system.Script:
-		var path string
-		path, err = initialize.PersistScriptInWorkspace(t, env.Workspace())
+	path, err := initialize.PersistScriptInWorkspace(script, env.Workspace())
 	if err == nil {
 		var name string
 		name, err = system.ExecuteScript(path)
 		initialize.PersistUnitNameInWorkspace(name, env.Workspace())
 	}
-	}
-
 	return err
 }
-
-func processNetconf(convertNetconf, configdrive string) error {
-	openstackRoot := path.Join(configdrive, "openstack")
-	metadataFilename := path.Join(openstackRoot, "latest", "meta_data.json")
-	metadataBytes, err := ioutil.ReadFile(metadataFilename)
-	if err != nil {
-		return err
-	}
-
-	var metadata struct {
-		NetworkConfig struct {
-			ContentPath string `json:"content_path"`
-		} `json:"network_config"`
-	}
-	if err := json.Unmarshal(metadataBytes, &metadata); err != nil {
-		return err
-	}
-	configPath := metadata.NetworkConfig.ContentPath
-	if configPath == "" {
-		fmt.Printf("No network config specified in %q.\n", metadataFilename)
-		return nil
-	}
-
-	netconfBytes, err := ioutil.ReadFile(path.Join(openstackRoot, configPath))
-	if err != nil {
-		return err
-	}
-
-	var interfaces []network.InterfaceGenerator
-	switch convertNetconf {
-	case "debian":
-		interfaces, err = network.ProcessDebianNetconf(string(netconfBytes))
-	default:
-		return fmt.Errorf("Unsupported network config format %q", convertNetconf)
-	}
-
-	if err != nil {
-		return err
-	}
-
-	if err := system.WriteNetworkdConfigs(interfaces); err != nil {
-		return err
-	}
-	return system.RestartNetwork(interfaces)
-}

coreos-cloudinit_test.go

@@ -0,0 +1,110 @@
+package main
+
+import (
+	"reflect"
+	"testing"
+
+	"github.com/coreos/coreos-cloudinit/initialize"
+)
+
+func TestMergeCloudConfig(t *testing.T) {
+	simplecc := initialize.CloudConfig{
+		SSHAuthorizedKeys: []string{"abc", "def"},
+		Hostname:          "foobar",
+		NetworkConfigPath: "/path/somewhere",
+	}
+	for i, tt := range []struct {
+		udcc initialize.CloudConfig
+		mdcc initialize.CloudConfig
+		want initialize.CloudConfig
+	}{
+		{
+			// If mdcc is empty, udcc should be returned unchanged
+			simplecc,
+			initialize.CloudConfig{},
+			simplecc,
+		},
+		{
+			// If udcc is empty, mdcc should be returned unchanged(overridden)
+			initialize.CloudConfig{},
+			simplecc,
+			simplecc,
+		},
+		{
+			// user-data should override completely in the case of conflicts
+			simplecc,
+			initialize.CloudConfig{
+				Hostname:          "meta-hostname",
+				NetworkConfigPath: "/path/meta",
+			},
+			simplecc,
+		},
+		{
+			// Mixed merge should succeed
+			initialize.CloudConfig{
+				SSHAuthorizedKeys: []string{"abc", "def"},
+				Hostname:          "user-hostname",
+				NetworkConfigPath: "/path/somewhere",
+			},
+			initialize.CloudConfig{
+				SSHAuthorizedKeys: []string{"woof", "qux"},
+				Hostname:          "meta-hostname",
+			},
+			initialize.CloudConfig{
+				SSHAuthorizedKeys: []string{"abc", "def", "woof", "qux"},
+				Hostname:          "user-hostname",
+				NetworkConfigPath: "/path/somewhere",
+			},
+		},
+		{
+			// Completely non-conflicting merge should be fine
+			initialize.CloudConfig{
+				Hostname: "supercool",
+			},
+			initialize.CloudConfig{
+				SSHAuthorizedKeys: []string{"zaphod", "beeblebrox"},
+				NetworkConfigPath: "/dev/fun",
+			},
+			initialize.CloudConfig{
+				Hostname:          "supercool",
+				SSHAuthorizedKeys: []string{"zaphod", "beeblebrox"},
+				NetworkConfigPath: "/dev/fun",
+			},
+		},
+		{
+			// Non-mergeable settings in user-data should not be affected
+			initialize.CloudConfig{
+				Hostname:       "mememe",
+				ManageEtcHosts: initialize.EtcHosts("lolz"),
+			},
+			initialize.CloudConfig{
+				Hostname:          "youyouyou",
+				NetworkConfigPath: "meta-meta-yo",
+			},
+			initialize.CloudConfig{
+				Hostname:          "mememe",
+				ManageEtcHosts:    initialize.EtcHosts("lolz"),
+				NetworkConfigPath: "meta-meta-yo",
+			},
+		},
+		{
+			// Non-mergeable (unexpected) settings in meta-data are ignored
+			initialize.CloudConfig{
+				Hostname: "mememe",
+			},
+			initialize.CloudConfig{
+				ManageEtcHosts:    initialize.EtcHosts("lolz"),
+				NetworkConfigPath: "meta-meta-yo",
+			},
+			initialize.CloudConfig{
+				Hostname:          "mememe",
+				NetworkConfigPath: "meta-meta-yo",
+			},
+		},
+	} {
+		got := mergeCloudConfig(tt.mdcc, tt.udcc)
+		if !reflect.DeepEqual(got, tt.want) {
+			t.Errorf("case #%d: mergeCloudConfig mutated CloudConfig unexpectedly:\ngot:\n%s\nwant:\n%s", i, got, tt.want)
+		}
+	}
+}

datasource/configdrive.go

@@ -7,21 +7,42 @@ import (
 )
 
 type configDrive struct {
-	path string
+	root string
 }
 
-func NewConfigDrive(path string) *configDrive {
-	return &configDrive{path}
+func NewConfigDrive(root string) *configDrive {
+	return &configDrive{path.Join(root, "openstack")}
 }
 
-func (self *configDrive) Fetch() ([]byte, error) {
-	data, err := ioutil.ReadFile(path.Join(self.path, "openstack", "latest", "user_data"))
+func (cd *configDrive) IsAvailable() bool {
+	_, err := os.Stat(cd.root)
+	return !os.IsNotExist(err)
+}
+
+func (cd *configDrive) AvailabilityChanges() bool {
+	return true
+}
+
+func (cd *configDrive) ConfigRoot() string {
+	return cd.root
+}
+
+func (cd *configDrive) FetchMetadata() ([]byte, error) {
+	return cd.readFile("meta_data.json")
+}
+
+func (cd *configDrive) FetchUserdata() ([]byte, error) {
+	return cd.readFile("user_data")
+}
+
+func (cd *configDrive) Type() string {
+	return "cloud-drive"
+}
+
+func (cd *configDrive) readFile(filename string) ([]byte, error) {
+	data, err := ioutil.ReadFile(path.Join(cd.root, "latest", filename))
 	if os.IsNotExist(err) {
 		err = nil
 	}
 	return data, err
 }
-
-func (self *configDrive) Type() string {
-	return "cloud-drive"
-}

datasource/datasource.go

@@ -1,6 +1,10 @@
 package datasource
 
 type Datasource interface {
-	Fetch() ([]byte, error)
+	IsAvailable() bool
+	AvailabilityChanges() bool
+	ConfigRoot() string
+	FetchMetadata() ([]byte, error)
+	FetchUserdata() ([]byte, error)
 	Type() string
 }

datasource/file.go

@@ -2,6 +2,7 @@ package datasource
 
 import (
 	"io/ioutil"
+	"os"
 )
 
 type localFile struct {
@@ -12,10 +13,27 @@ func NewLocalFile(path string) *localFile {
 	return &localFile{path}
 }
 
-func (self *localFile) Fetch() ([]byte, error) {
-	return ioutil.ReadFile(self.path)
+func (f *localFile) IsAvailable() bool {
+	_, err := os.Stat(f.path)
+	return !os.IsNotExist(err)
 }
 
-func (self *localFile) Type() string {
+func (f *localFile) AvailabilityChanges() bool {
+	return true
+}
+
+func (f *localFile) ConfigRoot() string {
+	return ""
+}
+
+func (f *localFile) FetchMetadata() ([]byte, error) {
+	return []byte{}, nil
+}
+
+func (f *localFile) FetchUserdata() ([]byte, error) {
+	return ioutil.ReadFile(f.path)
+}
+
+func (f *localFile) Type() string {
 	return "local-file"
 }

datasource/metadata_service.go

@@ -1,20 +1,155 @@
 package datasource
 
-import "github.com/coreos/coreos-cloudinit/pkg"
+import (
+	"bufio"
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"strings"
 
-type metadataService struct {
-	url string
+	"github.com/coreos/coreos-cloudinit/pkg"
+)
+
+// metadataService retrieves metadata from either an OpenStack[1] (2012-08-10)
+// or EC2[2] (2009-04-04) compatible endpoint. It will first attempt to
+// directly retrieve a JSON blob from the OpenStack endpoint. If that fails
+// with a 404, it then attempts to retrieve metadata bit-by-bit from the EC2
+// endpoint, and populates that into an equivalent JSON blob. metadataService
+// also checks for userdata from EC2 and, if that fails with a 404, OpenStack.
+//
+// [1] http://docs.openstack.org/grizzly/openstack-compute/admin/content/metadata-service.html
+// [2] http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/AESDG-chapter-instancedata.html#instancedata-data-categories
+
+const (
+	BaseUrl              = "http://169.254.169.254/"
+	Ec2ApiVersion        = "2009-04-04"
+	Ec2UserdataUrl       = BaseUrl + Ec2ApiVersion + "/user-data"
+	Ec2MetadataUrl       = BaseUrl + Ec2ApiVersion + "/meta-data"
+	OpenstackApiVersion  = "openstack/2012-08-10"
+	OpenstackUserdataUrl = BaseUrl + OpenstackApiVersion + "/user_data"
+)
+
+type metadataService struct{}
+
+type getter interface {
+	GetRetry(string) ([]byte, error)
 }
 
-func NewMetadataService(url string) *metadataService {
-	return &metadataService{url}
+func NewMetadataService() *metadataService {
+	return &metadataService{}
 }
 
-func (ms *metadataService) Fetch() ([]byte, error) {
+func (ms *metadataService) IsAvailable() bool {
 	client := pkg.NewHttpClient()
-	return client.Get(ms.url)
+	_, err := client.Get(BaseUrl)
+	return (err == nil)
+}
+
+func (ms *metadataService) AvailabilityChanges() bool {
+	return true
+}
+
+func (ms *metadataService) ConfigRoot() string {
+	return ""
+}
+
+func (ms *metadataService) FetchMetadata() ([]byte, error) {
+	return fetchMetadata(pkg.NewHttpClient())
+}
+
+func (ms *metadataService) FetchUserdata() ([]byte, error) {
+	client := pkg.NewHttpClient()
+	if data, err := client.GetRetry(Ec2UserdataUrl); err == nil {
+		return data, err
+	} else if _, ok := err.(pkg.ErrTimeout); ok {
+		return data, err
+	}
+
+	if data, err := client.GetRetry(OpenstackUserdataUrl); err == nil {
+		return data, err
+	} else if _, ok := err.(pkg.ErrNotFound); ok {
+		return []byte{}, nil
+	} else {
+		return data, err
+	}
 }
 
 func (ms *metadataService) Type() string {
 	return "metadata-service"
 }
+
+func fetchMetadata(client getter) ([]byte, error) {
+	attrs := make(map[string]interface{})
+	if keynames, err := fetchAttributes(client, fmt.Sprintf("%s/public-keys", Ec2MetadataUrl)); err == nil {
+		keyIDs := make(map[string]string)
+		for _, keyname := range keynames {
+			tokens := strings.SplitN(keyname, "=", 2)
+			if len(tokens) != 2 {
+				return nil, fmt.Errorf("malformed public key: %q\n", keyname)
+			}
+			keyIDs[tokens[1]] = tokens[0]
+		}
+
+		keys := make(map[string]string)
+		for name, id := range keyIDs {
+			sshkey, err := fetchAttribute(client, fmt.Sprintf("%s/public-keys/%s/openssh-key", Ec2MetadataUrl, id))
+			if err != nil {
+				return nil, err
+			}
+			keys[name] = sshkey
+			fmt.Printf("Found SSH key for %q\n", name)
+		}
+		attrs["public_keys"] = keys
+	} else if _, ok := err.(pkg.ErrNotFound); !ok {
+		return nil, err
+	}
+
+	if hostname, err := fetchAttribute(client, fmt.Sprintf("%s/hostname", Ec2MetadataUrl)); err == nil {
+		attrs["hostname"] = hostname
+	} else if _, ok := err.(pkg.ErrNotFound); !ok {
+		return nil, err
+	}
+
+	if localAddr, err := fetchAttribute(client, fmt.Sprintf("%s/local-ipv4", Ec2MetadataUrl)); err == nil {
+		attrs["local-ipv4"] = localAddr
+	} else if _, ok := err.(pkg.ErrNotFound); !ok {
+		return nil, err
+	}
+
+	if publicAddr, err := fetchAttribute(client, fmt.Sprintf("%s/public-ipv4", Ec2MetadataUrl)); err == nil {
+		attrs["public-ipv4"] = publicAddr
+	} else if _, ok := err.(pkg.ErrNotFound); !ok {
+		return nil, err
+	}
+
+	if content_path, err := fetchAttribute(client, fmt.Sprintf("%s/network_config/content_path", Ec2MetadataUrl)); err == nil {
+		attrs["network_config"] = map[string]string{
+			"content_path": content_path,
+		}
+	} else if _, ok := err.(pkg.ErrNotFound); !ok {
+		return nil, err
+	}
+
+	return json.Marshal(attrs)
+}
+
+func fetchAttributes(client getter, url string) ([]string, error) {
+	resp, err := client.GetRetry(url)
+	if err != nil {
+		return nil, err
+	}
+	scanner := bufio.NewScanner(bytes.NewBuffer(resp))
+	data := make([]string, 0)
+	for scanner.Scan() {
+		data = append(data, scanner.Text())
+	}
+	return data, scanner.Err()
+}
+
+func fetchAttribute(client getter, url string) (string, error) {
+	if attrs, err := fetchAttributes(client, url); err == nil && len(attrs) > 0 {
+		return attrs[0], nil
+	} else {
+		return "", err
+	}
+}

datasource/metadata_service_test.go

@@ -0,0 +1,159 @@
+package datasource
+
+import (
+	"bytes"
+	"fmt"
+	"reflect"
+	"testing"
+
+	"github.com/coreos/coreos-cloudinit/pkg"
+)
+
+type TestHttpClient struct {
+	metadata map[string]string
+	err      error
+}
+
+func (t *TestHttpClient) GetRetry(url string) ([]byte, error) {
+	if t.err != nil {
+		return nil, t.err
+	}
+	if val, ok := t.metadata[url]; ok {
+		return []byte(val), nil
+	} else {
+		return nil, pkg.ErrNotFound{fmt.Errorf("not found: %q", url)}
+	}
+}
+
+func TestFetchAttributes(t *testing.T) {
+	for _, s := range []struct {
+		metadata map[string]string
+		err      error
+		tests    []struct {
+			path string
+			val  []string
+		}
+	}{
+		{
+			metadata: map[string]string{
+				"/":      "a\nb\nc/",
+				"/c/":    "d\ne/",
+				"/c/e/":  "f",
+				"/a":     "1",
+				"/b":     "2",
+				"/c/d":   "3",
+				"/c/e/f": "4",
+			},
+			tests: []struct {
+				path string
+				val  []string
+			}{
+				{"/", []string{"a", "b", "c/"}},
+				{"/b", []string{"2"}},
+				{"/c/d", []string{"3"}},
+				{"/c/e/", []string{"f"}},
+			},
+		},
+		{
+			err: pkg.ErrNotFound{fmt.Errorf("test error")},
+			tests: []struct {
+				path string
+				val  []string
+			}{
+				{"", nil},
+			},
+		},
+	} {
+		client := &TestHttpClient{s.metadata, s.err}
+		for _, tt := range s.tests {
+			attrs, err := fetchAttributes(client, tt.path)
+			if err != s.err {
+				t.Fatalf("bad error for %q (%q): want %q, got %q", tt.path, s.metadata, s.err, err)
+			}
+			if !reflect.DeepEqual(attrs, tt.val) {
+				t.Fatalf("bad fetch for %q (%q): want %q, got %q", tt.path, s.metadata, tt.val, attrs)
+			}
+		}
+	}
+}
+
+func TestFetchAttribute(t *testing.T) {
+	for _, s := range []struct {
+		metadata map[string]string
+		err      error
+		tests    []struct {
+			path string
+			val  string
+		}
+	}{
+		{
+			metadata: map[string]string{
+				"/":      "a\nb\nc/",
+				"/c/":    "d\ne/",
+				"/c/e/":  "f",
+				"/a":     "1",
+				"/b":     "2",
+				"/c/d":   "3",
+				"/c/e/f": "4",
+			},
+			tests: []struct {
+				path string
+				val  string
+			}{
+				{"/a", "1"},
+				{"/b", "2"},
+				{"/c/d", "3"},
+				{"/c/e/f", "4"},
+			},
+		},
+		{
+			err: pkg.ErrNotFound{fmt.Errorf("test error")},
+			tests: []struct {
+				path string
+				val  string
+			}{
+				{"", ""},
+			},
+		},
+	} {
+		client := &TestHttpClient{s.metadata, s.err}
+		for _, tt := range s.tests {
+			attr, err := fetchAttribute(client, tt.path)
+			if err != s.err {
+				t.Fatalf("bad error for %q (%q): want %q, got %q", tt.path, s.metadata, s.err, err)
+			}
+			if attr != tt.val {
+				t.Fatalf("bad fetch for %q (%q): want %q, got %q", tt.path, s.metadata, tt.val, attr)
+			}
+		}
+	}
+}
+
+func TestFetchMetadata(t *testing.T) {
+	for _, tt := range []struct {
+		metadata map[string]string
+		err      error
+		expect   []byte
+	}{
+		{
+			metadata: map[string]string{
+				"http://169.254.169.254/2009-04-04/meta-data/hostname":                    "host",
+				"http://169.254.169.254/2009-04-04/meta-data/public-keys":                 "0=test1\n",
+				"http://169.254.169.254/2009-04-04/meta-data/public-keys/0":               "openssh-key",
+				"http://169.254.169.254/2009-04-04/meta-data/public-keys/0/openssh-key":   "key",
+				"http://169.254.169.254/2009-04-04/meta-data/network_config/content_path": "path",
+			},
+			expect: []byte(`{"hostname":"host","network_config":{"content_path":"path"},"public_keys":{"test1":"key"}}`),
+		},
+		{err: pkg.ErrTimeout{fmt.Errorf("test error")}},
+	} {
+		client := &TestHttpClient{tt.metadata, tt.err}
+		metadata, err := fetchMetadata(client)
+		if err != tt.err {
+			t.Fatalf("bad error (%q): want %q, got %q", tt.metadata, tt.err, err)
+		}
+		if !bytes.Equal(metadata, tt.expect) {
+			t.Fatalf("bad fetch (%q): want %q, got %q", tt.metadata, tt.expect, metadata)
+		}
+	}
+}

datasource/proc_cmdline.go

@@ -14,7 +14,7 @@ const (
 	ProcCmdlineCloudConfigFlag = "cloud-config-url"
 )
 
-type procCmdline struct{
+type procCmdline struct {
 	Location string
 }
 
@@ -22,8 +22,31 @@ func NewProcCmdline() *procCmdline {
 	return &procCmdline{Location: ProcCmdlineLocation}
 }
 
-func (self *procCmdline) Fetch() ([]byte, error) {
-	contents, err := ioutil.ReadFile(self.Location)
+func (c *procCmdline) IsAvailable() bool {
+	contents, err := ioutil.ReadFile(c.Location)
+	if err != nil {
+		return false
+	}
+
+	cmdline := strings.TrimSpace(string(contents))
+	_, err = findCloudConfigURL(cmdline)
+	return (err == nil)
+}
+
+func (c *procCmdline) AvailabilityChanges() bool {
+	return false
+}
+
+func (c *procCmdline) ConfigRoot() string {
+	return ""
+}
+
+func (c *procCmdline) FetchMetadata() ([]byte, error) {
+	return []byte{}, nil
+}
+
+func (c *procCmdline) FetchUserdata() ([]byte, error) {
+	contents, err := ioutil.ReadFile(c.Location)
 	if err != nil {
 		return nil, err
 	}
@@ -35,7 +58,7 @@ func (self *procCmdline) Fetch() ([]byte, error) {
 	}
 
 	client := pkg.NewHttpClient()
-	cfg, err := client.Get(url)
+	cfg, err := client.GetRetry(url)
 	if err != nil {
 		return nil, err
 	}
@@ -43,7 +66,7 @@ func (self *procCmdline) Fetch() ([]byte, error) {
 	return cfg, nil
 }
 
-func (self *procCmdline) Type() string {
+func (c *procCmdline) Type() string {
 	return "proc-cmdline"
 }
 

datasource/proc_cmdline_test.go

@@ -77,7 +77,7 @@ func TestProcCmdlineAndFetchConfig(t *testing.T) {
 
 	p := NewProcCmdline()
 	p.Location = file.Name()
-	cfg, err := p.Fetch()
+	cfg, err := p.FetchUserdata()
 	if err != nil {
 		t.Errorf("Test produced error: %v", err)
 	}

datasource/url.go

@@ -0,0 +1,38 @@
+package datasource
+
+import "github.com/coreos/coreos-cloudinit/pkg"
+
+type remoteFile struct {
+	url string
+}
+
+func NewRemoteFile(url string) *remoteFile {
+	return &remoteFile{url}
+}
+
+func (f *remoteFile) IsAvailable() bool {
+	client := pkg.NewHttpClient()
+	_, err := client.Get(f.url)
+	return (err == nil)
+}
+
+func (f *remoteFile) AvailabilityChanges() bool {
+	return true
+}
+
+func (f *remoteFile) ConfigRoot() string {
+	return ""
+}
+
+func (f *remoteFile) FetchMetadata() ([]byte, error) {
+	return []byte{}, nil
+}
+
+func (f *remoteFile) FetchUserdata() ([]byte, error) {
+	client := pkg.NewHttpClient()
+	return client.GetRetry(f.url)
+}
+
+func (f *remoteFile) Type() string {
+	return "url"
+}

initialize/config.go

@@ -3,10 +3,13 @@ package initialize
 import (
 	"errors"
 	"fmt"
+	"io/ioutil"
 	"log"
+	"path"
 
 	"github.com/coreos/coreos-cloudinit/third_party/launchpad.net/goyaml"
 
+	"github.com/coreos/coreos-cloudinit/network"
 	"github.com/coreos/coreos-cloudinit/system"
 )
 
@@ -38,6 +41,7 @@ type CloudConfig struct {
 	Hostname          string
 	Users             []system.User
 	ManageEtcHosts    EtcHosts `yaml:"manage_etc_hosts"`
+	NetworkConfigPath string
 }
 
 type warner func(format string, v ...interface{})
@@ -219,21 +223,72 @@ func Apply(cfg CloudConfig, env *Environment) error {
 		cfg.Coreos.Units = append(cfg.Coreos.Units, u...)
 	}
 
+	wroteEnvironment := false
 	for _, file := range cfg.WriteFiles {
-		path, err := system.WriteFile(&file, env.Root())
+		fullPath, err := system.WriteFile(&file, env.Root())
 		if err != nil {
 			return err
 		}
-		log.Printf("Wrote file %s to filesystem", path)
+		if path.Clean(file.Path) == "/etc/environment" {
+			wroteEnvironment = true
+		}
+		log.Printf("Wrote file %s to filesystem", fullPath)
 	}
 
+	if !wroteEnvironment {
+		ef := env.DefaultEnvironmentFile()
+		if ef != nil {
+			err := system.WriteEnvFile(ef, env.Root())
+			if err != nil {
+				return err
+			}
+			log.Printf("Updated /etc/environment")
+		}
+	}
+
+	if env.NetconfType() != "" {
+		netconfBytes, err := ioutil.ReadFile(path.Join(env.ConfigRoot(), cfg.NetworkConfigPath))
+		if err != nil {
+			return err
+		}
+
+		var interfaces []network.InterfaceGenerator
+		switch env.NetconfType() {
+		case "debian":
+			interfaces, err = network.ProcessDebianNetconf(string(netconfBytes))
+		default:
+			return fmt.Errorf("Unsupported network config format %q", env.NetconfType())
+		}
+
+		if err != nil {
+			return err
+		}
+
+		if err := system.WriteNetworkdConfigs(interfaces); err != nil {
+			return err
+		}
+		if err := system.RestartNetwork(interfaces); err != nil {
+			return err
+		}
+	}
+
+	um := system.NewUnitManager(env.Root())
+	return processUnits(cfg.Coreos.Units, env.Root(), um)
+
+}
+
+// processUnits takes a set of Units and applies them to the given root using
+// the given UnitManager. This can involve things like writing unit files to
+// disk, masking/unmasking units, or invoking systemd
+// commands against units. It returns any error encountered.
+func processUnits(units []system.Unit, root string, um system.UnitManager) error {
 	commands := make(map[string]string, 0)
 	reload := false
-	for _, unit := range cfg.Coreos.Units {
-		dst := unit.Destination(env.Root())
+	for _, unit := range units {
+		dst := unit.Destination(root)
 		if unit.Content != "" {
 			log.Printf("Writing unit %s to filesystem at path %s", unit.Name, dst)
-			if err := system.PlaceUnit(&unit, dst); err != nil {
+			if err := um.PlaceUnit(&unit, dst); err != nil {
 				return err
 			}
 			log.Printf("Placed unit %s at %s", unit.Name, dst)
@@ -242,12 +297,12 @@ func Apply(cfg CloudConfig, env *Environment) error {
 
 		if unit.Mask {
 			log.Printf("Masking unit file %s", unit.Name)
-			if err := system.MaskUnit(&unit, env.Root()); err != nil {
+			if err := um.MaskUnit(&unit); err != nil {
 				return err
 			}
 		} else if unit.Runtime {
 			log.Printf("Ensuring runtime unit file %s is unmasked", unit.Name)
-			if err := system.UnmaskUnit(&unit, env.Root()); err != nil {
+			if err := um.UnmaskUnit(&unit); err != nil {
 				return err
 			}
 		}
@@ -255,7 +310,7 @@ func Apply(cfg CloudConfig, env *Environment) error {
 		if unit.Enable {
 			if unit.Group() != "network" {
 				log.Printf("Enabling unit file %s", unit.Name)
-				if err := system.EnableUnitFile(unit.Name, unit.Runtime); err != nil {
+				if err := um.EnableUnitFile(unit.Name, unit.Runtime); err != nil {
 					return err
 				}
 				log.Printf("Enabled unit %s", unit.Name)
@@ -272,14 +327,14 @@ func Apply(cfg CloudConfig, env *Environment) error {
 	}
 
 	if reload {
-		if err := system.DaemonReload(); err != nil {
+		if err := um.DaemonReload(); err != nil {
 			return errors.New(fmt.Sprintf("failed systemd daemon-reload: %v", err))
 		}
 	}
 
 	for unit, command := range commands {
 		log.Printf("Calling unit command '%s %s'", command, unit)
-		res, err := system.RunUnitCommand(command, unit)
+		res, err := um.RunUnitCommand(command, unit)
 		if err != nil {
 			return err
 		}

initialize/config_test.go

@@ -4,6 +4,8 @@ import (
 	"fmt"
 	"strings"
 	"testing"
+
+	"github.com/coreos/coreos-cloudinit/system"
 )
 
 func TestCloudConfigUnknownKeys(t *testing.T) {
@@ -332,3 +334,109 @@ users:
 		t.Errorf("Failed to parse no-log-init field")
 	}
 }
+
+type TestUnitManager struct {
+	placed   []string
+	enabled  []string
+	masked   []string
+	unmasked []string
+	commands map[string]string
+	reload   bool
+}
+
+func (tum *TestUnitManager) PlaceUnit(unit *system.Unit, dst string) error {
+	tum.placed = append(tum.placed, unit.Name)
+	return nil
+}
+func (tum *TestUnitManager) EnableUnitFile(unit string, runtime bool) error {
+	tum.enabled = append(tum.enabled, unit)
+	return nil
+}
+func (tum *TestUnitManager) RunUnitCommand(command, unit string) (string, error) {
+	tum.commands = make(map[string]string)
+	tum.commands[unit] = command
+	return "", nil
+}
+func (tum *TestUnitManager) DaemonReload() error {
+	tum.reload = true
+	return nil
+}
+func (tum *TestUnitManager) MaskUnit(unit *system.Unit) error {
+	tum.masked = append(tum.masked, unit.Name)
+	return nil
+}
+func (tum *TestUnitManager) UnmaskUnit(unit *system.Unit) error {
+	tum.unmasked = append(tum.unmasked, unit.Name)
+	return nil
+}
+
+func TestProcessUnits(t *testing.T) {
+	tum := &TestUnitManager{}
+	units := []system.Unit{
+		system.Unit{
+			Name: "foo",
+			Mask: true,
+		},
+	}
+	if err := processUnits(units, "", tum); err != nil {
+		t.Fatalf("unexpected error calling processUnits: %v", err)
+	}
+	if len(tum.masked) != 1 || tum.masked[0] != "foo" {
+		t.Errorf("expected foo to be masked, but found %v", tum.masked)
+	}
+
+	tum = &TestUnitManager{}
+	units = []system.Unit{
+		system.Unit{
+			Name: "bar.network",
+		},
+	}
+	if err := processUnits(units, "", tum); err != nil {
+		t.Fatalf("unexpected error calling processUnits: %v", err)
+	}
+	if _, ok := tum.commands["systemd-networkd.service"]; !ok {
+		t.Errorf("expected systemd-networkd.service to be reloaded!")
+	}
+
+	tum = &TestUnitManager{}
+	units = []system.Unit{
+		system.Unit{
+			Name:    "baz.service",
+			Content: "[Service]\nExecStart=/bin/true",
+		},
+	}
+	if err := processUnits(units, "", tum); err != nil {
+		t.Fatalf("unexpected error calling processUnits: %v", err)
+	}
+	if len(tum.placed) != 1 || tum.placed[0] != "baz.service" {
+		t.Fatalf("expected baz.service to be written, but got %v", tum.placed)
+	}
+
+	tum = &TestUnitManager{}
+	units = []system.Unit{
+		system.Unit{
+			Name:    "locksmithd.service",
+			Runtime: true,
+		},
+	}
+	if err := processUnits(units, "", tum); err != nil {
+		t.Fatalf("unexpected error calling processUnits: %v", err)
+	}
+	if len(tum.unmasked) != 1 || tum.unmasked[0] != "locksmithd.service" {
+		t.Fatalf("expected locksmithd.service to be unmasked, but got %v", tum.unmasked)
+	}
+
+	tum = &TestUnitManager{}
+	units = []system.Unit{
+		system.Unit{
+			Name:   "woof",
+			Enable: true,
+		},
+	}
+	if err := processUnits(units, "", tum); err != nil {
+		t.Fatalf("unexpected error calling processUnits: %v", err)
+	}
+	if len(tum.enabled) != 1 || tum.enabled[0] != "woof" {
+		t.Fatalf("expected woof to be enabled, but got %v", tum.enabled)
+	}
+}

initialize/env.go

@@ -4,48 +4,89 @@ import (
 	"os"
 	"path"
 	"strings"
+
+	"github.com/coreos/coreos-cloudinit/system"
 )
 
 const DefaultSSHKeyName = "coreos-cloudinit"
 
 type Environment struct {
 	root          string
+	configRoot    string
 	workspace     string
+	netconfType   string
 	sshKeyName    string
 	substitutions map[string]string
 }
 
-func NewEnvironment(root, workspace string) *Environment {
-	substitutions := map[string]string{
+// TODO(jonboulle): this is getting unwieldy, should be able to simplify the interface somehow
+func NewEnvironment(root, configRoot, workspace, netconfType, sshKeyName string, substitutions map[string]string) *Environment {
+	if substitutions == nil {
+		substitutions = make(map[string]string)
+	}
+	// If certain values are not in the supplied substitution, fall back to retrieving them from the environment
+	for k, v := range map[string]string{
 		"$public_ipv4":  os.Getenv("COREOS_PUBLIC_IPV4"),
 		"$private_ipv4": os.Getenv("COREOS_PRIVATE_IPV4"),
+	} {
+		if _, ok := substitutions[k]; !ok {
+			substitutions[k] = v
 		}
-	return &Environment{root, workspace, DefaultSSHKeyName, substitutions}
+	}
+	return &Environment{root, configRoot, workspace, netconfType, sshKeyName, substitutions}
 }
 
-func (self *Environment) Workspace() string {
-	return path.Join(self.root, self.workspace)
+func (e *Environment) Workspace() string {
+	return path.Join(e.root, e.workspace)
 }
 
-func (self *Environment) Root() string {
-	return self.root
+func (e *Environment) Root() string {
+	return e.root
 }
 
-func (self *Environment) SSHKeyName() string {
-	return self.sshKeyName
+func (e *Environment) ConfigRoot() string {
+	return e.configRoot
 }
 
-func (self *Environment) SetSSHKeyName(name string) {
-	self.sshKeyName = name
+func (e *Environment) NetconfType() string {
+	return e.netconfType
 }
 
-func (self *Environment) Apply(data string) string {
-	for key, val := range self.substitutions {
+func (e *Environment) SSHKeyName() string {
+	return e.sshKeyName
+}
+
+func (e *Environment) SetSSHKeyName(name string) {
+	e.sshKeyName = name
+}
+
+func (e *Environment) Apply(data string) string {
+	for key, val := range e.substitutions {
 		data = strings.Replace(data, key, val, -1)
 	}
 	return data
 }
 
+func (e *Environment) DefaultEnvironmentFile() *system.EnvFile {
+	ef := system.EnvFile{
+		File: &system.File{
+			Path: "/etc/environment",
+		},
+		Vars: map[string]string{},
+	}
+	if ip, ok := e.substitutions["$public_ipv4"]; ok && len(ip) > 0 {
+		ef.Vars["COREOS_PUBLIC_IPV4"] = ip
+	}
+	if ip, ok := e.substitutions["$private_ipv4"]; ok && len(ip) > 0 {
+		ef.Vars["COREOS_PRIVATE_IPV4"] = ip
+	}
+	if len(ef.Vars) == 0 {
+		return nil
+	} else {
+		return &ef
+	}
+}
+
 // normalizeSvcEnv standardizes the keys of the map (environment variables for a service)
 // by replacing any dashes with underscores and ensuring they are entirely upper case.
 // For example, "some-env" --> "SOME_ENV"

initialize/env_test.go

@@ -1,27 +1,106 @@
 package initialize
 
 import (
+	"io/ioutil"
 	"os"
+	"path"
 	"testing"
+
+	"github.com/coreos/coreos-cloudinit/system"
 )
 
 func TestEnvironmentApply(t *testing.T) {
-	os.Setenv("COREOS_PUBLIC_IPV4", "192.0.2.3")
-	os.Setenv("COREOS_PRIVATE_IPV4", "192.0.2.203")
-	env := NewEnvironment("./", "./")
-	input := `[Service]
+	os.Setenv("COREOS_PUBLIC_IPV4", "1.2.3.4")
+	os.Setenv("COREOS_PRIVATE_IPV4", "5.6.7.8")
+	for _, tt := range []struct {
+		subs  map[string]string
+		input string
+		out   string
+	}{
+		{
+			// Substituting both values directly should always take precedence
+			// over environment variables
+			map[string]string{
+				"$public_ipv4":  "192.0.2.3",
+				"$private_ipv4": "192.0.2.203",
+			},
+			`[Service]
 ExecStart=/usr/bin/echo "$public_ipv4"
 ExecStop=/usr/bin/echo $private_ipv4
-ExecStop=/usr/bin/echo $unknown
-`
-	expected := `[Service]
+ExecStop=/usr/bin/echo $unknown`,
+			`[Service]
 ExecStart=/usr/bin/echo "192.0.2.3"
 ExecStop=/usr/bin/echo 192.0.2.203
-ExecStop=/usr/bin/echo $unknown
-`
+ExecStop=/usr/bin/echo $unknown`,
+		},
+		{
+			// Substituting one value directly while falling back with the other
+			map[string]string{"$private_ipv4": "127.0.0.1"},
+			"$private_ipv4\n$public_ipv4",
+			"127.0.0.1\n1.2.3.4",
+		},
+		{
+			// Falling back to environment variables for both values
+			map[string]string{"foo": "bar"},
+			"$private_ipv4\n$public_ipv4",
+			"5.6.7.8\n1.2.3.4",
+		},
+		{
+			// No substitutions
+			nil,
+			"$private_ipv4\nfoobar",
+			"5.6.7.8\nfoobar",
+		},
+	} {
 
-	output := env.Apply(input)
-	if output != expected {
-		t.Fatalf("Environment incorrectly applied.\nOutput:\n%s\nExpected:\n%s", output, expected)
+		env := NewEnvironment("./", "./", "./", "", "", tt.subs)
+		got := env.Apply(tt.input)
+		if got != tt.out {
+			t.Fatalf("Environment incorrectly applied.\ngot:\n%s\nwant:\n%s", got, tt.out)
+		}
+	}
+}
+
+func TestEnvironmentFile(t *testing.T) {
+	subs := map[string]string{
+		"$public_ipv4":  "1.2.3.4",
+		"$private_ipv4": "5.6.7.8",
+	}
+	expect := "COREOS_PUBLIC_IPV4=1.2.3.4\nCOREOS_PRIVATE_IPV4=5.6.7.8\n"
+
+	dir, err := ioutil.TempDir(os.TempDir(), "coreos-cloudinit-")
+	if err != nil {
+		t.Fatalf("Unable to create tempdir: %v", err)
+	}
+	defer os.RemoveAll(dir)
+
+	env := NewEnvironment("./", "./", "./", "", "", subs)
+	ef := env.DefaultEnvironmentFile()
+	err = system.WriteEnvFile(ef, dir)
+	if err != nil {
+		t.Fatalf("WriteEnvFile failed: %v", err)
+	}
+
+	fullPath := path.Join(dir, "etc", "environment")
+	contents, err := ioutil.ReadFile(fullPath)
+	if err != nil {
+		t.Fatalf("Unable to read expected file: %v", err)
+	}
+
+	if string(contents) != expect {
+		t.Fatalf("File has incorrect contents: %q", contents)
+	}
+}
+
+func TestEnvironmentFileNil(t *testing.T) {
+	subs := map[string]string{
+		"$public_ipv4":  "",
+		"$private_ipv4": "",
+	}
+
+	env := NewEnvironment("./", "./", "./", "", "", subs)
+	ef := env.DefaultEnvironmentFile()
+	if ef != nil {
+		t.Fatalf("Environment file not nil: %v", ef)
 	}
 }

initialize/etcd.go

@@ -3,6 +3,7 @@ package initialize
 import (
 	"errors"
 	"fmt"
+	"sort"
 
 	"github.com/coreos/coreos-cloudinit/system"
 )
@@ -19,9 +20,16 @@ func (ee EtcdEnvironment) String() (out string) {
 		}
 	}
 
+	var sorted sort.StringSlice
+	for k, _ := range norm {
+		sorted = append(sorted, k)
+	}
+	sorted.Sort()
+
 	out += "[Service]\n"
 
-	for key, val := range norm {
+	for _, key := range sorted {
+		val := norm[key]
 		out += fmt.Sprintf("Environment=\"ETCD_%s=%s\"\n", key, val)
 	}
 

initialize/etcd_test.go

@@ -70,6 +70,8 @@ func TestEtcdEnvironmentWrittenToDisk(t *testing.T) {
 	}
 	defer os.RemoveAll(dir)
 
+	sd := system.NewUnitManager(dir)
+
 	uu, err := ee.Units(dir)
 	if err != nil {
 		t.Fatalf("Generating etcd unit failed: %v", err)
@@ -81,7 +83,7 @@ func TestEtcdEnvironmentWrittenToDisk(t *testing.T) {
 
 	dst := u.Destination(dir)
 	os.Stderr.WriteString("writing to " + dir + "\n")
-	if err := system.PlaceUnit(&u, dst); err != nil {
+	if err := sd.PlaceUnit(&u, dst); err != nil {
 		t.Fatalf("Writing of EtcdEnvironment failed: %v", err)
 	}
 
@@ -102,8 +104,8 @@ func TestEtcdEnvironmentWrittenToDisk(t *testing.T) {
 	}
 
 	expect := `[Service]
-Environment="ETCD_NAME=node001"
 Environment="ETCD_DISCOVERY=http://disco.example.com/foobar"
+Environment="ETCD_NAME=node001"
 Environment="ETCD_PEER_BIND_ADDR=127.0.0.1:7002"
 `
 	if string(contents) != expect {
@@ -119,6 +121,8 @@ func TestEtcdEnvironmentWrittenToDiskDefaultToMachineID(t *testing.T) {
 	}
 	defer os.RemoveAll(dir)
 
+	sd := system.NewUnitManager(dir)
+
 	os.Mkdir(path.Join(dir, "etc"), os.FileMode(0755))
 	err = ioutil.WriteFile(path.Join(dir, "etc", "machine-id"), []byte("node007"), os.FileMode(0444))
 	if err != nil {
@@ -136,7 +140,7 @@ func TestEtcdEnvironmentWrittenToDiskDefaultToMachineID(t *testing.T) {
 
 	dst := u.Destination(dir)
 	os.Stderr.WriteString("writing to " + dir + "\n")
-	if err := system.PlaceUnit(&u, dst); err != nil {
+	if err := sd.PlaceUnit(&u, dst); err != nil {
 		t.Fatalf("Writing of EtcdEnvironment failed: %v", err)
 	}
 

initialize/meta_data.go

@@ -0,0 +1,52 @@
+package initialize
+
+import "encoding/json"
+
+// ParseMetaData parses a JSON blob in the OpenStack metadata service format, and
+// converts it to a partially hydrated CloudConfig
+func ParseMetaData(contents string) (*CloudConfig, error) {
+	if len(contents) == 0 {
+		return nil, nil
+	}
+	var metadata struct {
+		SSHAuthorizedKeyMap map[string]string `json:"public_keys"`
+		Hostname            string            `json:"hostname"`
+		NetworkConfig       struct {
+			ContentPath string `json:"content_path"`
+		} `json:"network_config"`
+	}
+	if err := json.Unmarshal([]byte(contents), &metadata); err != nil {
+		return nil, err
+	}
+
+	var cfg CloudConfig
+	if len(metadata.SSHAuthorizedKeyMap) > 0 {
+		cfg.SSHAuthorizedKeys = make([]string, 0, len(metadata.SSHAuthorizedKeyMap))
+		for _, key := range metadata.SSHAuthorizedKeyMap {
+			cfg.SSHAuthorizedKeys = append(cfg.SSHAuthorizedKeys, key)
+		}
+	}
+	cfg.Hostname = metadata.Hostname
+	cfg.NetworkConfigPath = metadata.NetworkConfig.ContentPath
+	return &cfg, nil
+}
+
+// ExtractIPsFromMetaData parses a JSON blob in the OpenStack metadata service format,
+// and returns a substitution map possibly containing private_ipv4 and public_ipv4 addresses
+func ExtractIPsFromMetadata(contents []byte) (map[string]string, error) {
+	var ips struct {
+		Public  string `json:"public-ipv4"`
+		Private string `json:"local-ipv4"`
+	}
+	if err := json.Unmarshal(contents, &ips); err != nil {
+		return nil, err
+	}
+	m := make(map[string]string)
+	if ips.Private != "" {
+		m["$private_ipv4"] = ips.Private
+	}
+	if ips.Public != "" {
+		m["$public_ipv4"] = ips.Public
+	}
+	return m, nil
+}

initialize/meta_data_test.go

@@ -0,0 +1,69 @@
+package initialize
+
+import "reflect"
+import "testing"
+
+func TestParseMetadata(t *testing.T) {
+	for i, tt := range []struct {
+		in   string
+		want *CloudConfig
+		err  bool
+	}{
+		{"", nil, false},
+		{`garbage, invalid json`, nil, true},
+		{`{"foo": "bar"}`, &CloudConfig{}, false},
+		{`{"network_config": {"content_path": "asdf"}}`, &CloudConfig{NetworkConfigPath: "asdf"}, false},
+		{`{"hostname": "turkleton"}`, &CloudConfig{Hostname: "turkleton"}, false},
+		{`{"public_keys": {"jack": "jill", "bob": "alice"}}`, &CloudConfig{SSHAuthorizedKeys: []string{"jill", "alice"}}, false},
+		{`{"unknown": "thing", "hostname": "my_host", "public_keys": {"do": "re", "mi": "fa"}, "network_config": {"content_path": "/root", "blah": "zzz"}}`, &CloudConfig{SSHAuthorizedKeys: []string{"re", "fa"}, Hostname: "my_host", NetworkConfigPath: "/root"}, false},
+	} {
+		got, err := ParseMetaData(tt.in)
+		if tt.err != (err != nil) {
+			t.Errorf("case #%d: bad error state: got %t, want %t (err=%v)", i, (err != nil), tt.err, err)
+		}
+		if got == nil {
+			if tt.want != nil {
+				t.Errorf("case #%d: unexpected nil output", i)
+			}
+		} else if tt.want == nil {
+			t.Errorf("case #%d: unexpected non-nil output", i)
+		} else {
+			if !reflect.DeepEqual(*got, *tt.want) {
+				t.Errorf("case #%d: bad output:\ngot\n%v\nwant\n%v", i, *got, *tt.want)
+			}
+		}
+	}
+
+}
+
+func TestExtractIPsFromMetadata(t *testing.T) {
+	for i, tt := range []struct {
+		in  []byte
+		err bool
+		out map[string]string
+	}{
+		{
+			[]byte(`{"public-ipv4": "12.34.56.78", "local-ipv4": "1.2.3.4"}`),
+			false,
+			map[string]string{"$public_ipv4": "12.34.56.78", "$private_ipv4": "1.2.3.4"},
+		},
+		{
+			[]byte(`{"local-ipv4": "127.0.0.1", "something_else": "don't care"}`),
+			false,
+			map[string]string{"$private_ipv4": "127.0.0.1"},
+		},
+		{
+			[]byte(`garbage`),
+			true,
+			nil,
+		},
+	} {
+		got, err := ExtractIPsFromMetadata(tt.in)
+		if (err != nil) != tt.err {
+			t.Errorf("bad error state (got %t, want %t)", err != nil, tt.err)
+		}
+		if !reflect.DeepEqual(got, tt.out) {
+			t.Errorf("case %d: got %s, want %s", i, got, tt.out)
+		}
+	}
+}

initialize/ssh_keys.go

@@ -25,7 +25,7 @@ func SSHImportKeysFromURL(system_user string, url string) error {
 
 func fetchUserKeys(url string) ([]string, error) {
 	client := pkg.NewHttpClient()
-	data, err := client.Get(url)
+	data, err := client.GetRetry(url)
 	if err != nil {
 		return nil, err
 	}

initialize/user_data.go

@@ -9,6 +9,9 @@ import (
 )
 
 func ParseUserData(contents string) (interface{}, error) {
+	if len(contents) == 0 {
+		return nil, nil
+	}
 	header := strings.SplitN(contents, "\n", 2)[0]
 
 	// Explicitly trim the header so we can handle user-data from
@@ -19,14 +22,9 @@ func ParseUserData(contents string) (interface{}, error) {
 	if strings.HasPrefix(header, "#!") {
 		log.Printf("Parsing user-data as script")
 		return system.Script(contents), nil
-
 	} else if header == "#cloud-config" {
 		log.Printf("Parsing user-data as cloud-config")
-		cfg, err := NewCloudConfig(contents)
-		if err != nil {
-			log.Fatal(err.Error())
-		}
-		return *cfg, nil
+		return NewCloudConfig(contents)
 	} else {
 		return nil, fmt.Errorf("Unrecognized user-data header: %s", header)
 	}

initialize/user_data_test.go

@@ -37,7 +37,7 @@ func TestParseConfigCRLF(t *testing.T) {
 		t.Fatalf("Failed parsing config: %v", err)
 	}
 
-	cfg := ud.(CloudConfig)
+	cfg := ud.(*CloudConfig)
 
 	if cfg.Hostname != "foo" {
 		t.Error("Failed parsing hostname from config")
@@ -47,3 +47,12 @@ func TestParseConfigCRLF(t *testing.T) {
 		t.Error("Parsed incorrect number of SSH keys")
 	}
 }
+
+func TestParseConfigEmpty(t *testing.T) {
+	i, e := ParseUserData(``)
+	if i != nil {
+		t.Error("ParseUserData of empty string returned non-nil unexpectedly")
+	} else if e != nil {
+		t.Error("ParseUserData of empty string returned error unexpectedly")
+	}
+}

network/interface.go

@@ -3,19 +3,30 @@ package network
 import (
 	"fmt"
 	"strconv"
+	"strings"
 )
 
 type InterfaceGenerator interface {
 	Name() string
+	Filename() string
 	Netdev() string
 	Link() string
 	Network() string
+	Type() string
+	ModprobeParams() string
+}
+
+type networkInterface interface {
+	InterfaceGenerator
+	Children() []networkInterface
+	setConfigDepth(int)
 }
 
 type logicalInterface struct {
 	name        string
 	config      configMethod
-	children []InterfaceGenerator
+	children    []networkInterface
+	configDepth int
 }
 
 func (i *logicalInterface) Network() string {
@@ -48,6 +59,26 @@ func (i *logicalInterface) Network() string {
 	return config
 }
 
+func (i *logicalInterface) Link() string {
+	return ""
+}
+
+func (i *logicalInterface) Filename() string {
+	return fmt.Sprintf("%02x-%s", i.configDepth, i.name)
+}
+
+func (i *logicalInterface) Children() []networkInterface {
+	return i.children
+}
+
+func (i *logicalInterface) ModprobeParams() string {
+	return ""
+}
+
+func (i *logicalInterface) setConfigDepth(depth int) {
+	i.configDepth = depth
+}
+
 type physicalInterface struct {
 	logicalInterface
 }
@@ -60,13 +91,14 @@ func (p *physicalInterface) Netdev() string {
 	return ""
 }
 
-func (p *physicalInterface) Link() string {
-	return ""
+func (p *physicalInterface) Type() string {
+	return "physical"
 }
 
 type bondInterface struct {
 	logicalInterface
 	slaves  []string
+	options map[string]string
 }
 
 func (b *bondInterface) Name() string {
@@ -77,8 +109,17 @@ func (b *bondInterface) Netdev() string {
 	return fmt.Sprintf("[NetDev]\nKind=bond\nName=%s\n", b.name)
 }
 
-func (b *bondInterface) Link() string {
-	return ""
+func (b *bondInterface) Type() string {
+	return "bond"
+}
+
+func (b *bondInterface) ModprobeParams() string {
+	params := ""
+	for name, val := range b.options {
+		params += fmt.Sprintf("%s=%s ", name, val)
+	}
+	params = strings.TrimSuffix(params, " ")
+	return params
 }
 
 type vlanInterface struct {
@@ -92,102 +133,161 @@ func (v *vlanInterface) Name() string {
 }
 
 func (v *vlanInterface) Netdev() string {
-	return fmt.Sprintf("[NetDev]\nKind=vlan\nName=%s\n\n[VLAN]\nId=%d\n", v.name, v.id)
+	config := fmt.Sprintf("[NetDev]\nKind=vlan\nName=%s\n", v.name)
+	switch c := v.config.(type) {
+	case configMethodStatic:
+		if c.hwaddress != nil {
+			config += fmt.Sprintf("MACAddress=%s\n", c.hwaddress)
+		}
+	case configMethodDHCP:
+		if c.hwaddress != nil {
+			config += fmt.Sprintf("MACAddress=%s\n", c.hwaddress)
+		}
+	}
+	config += fmt.Sprintf("\n[VLAN]\nId=%d\n", v.id)
+	return config
 }
 
-func (v *vlanInterface) Link() string {
-	return ""
+func (v *vlanInterface) Type() string {
+	return "vlan"
 }
 
 func buildInterfaces(stanzas []*stanzaInterface) []InterfaceGenerator {
-	bondStanzas := make(map[string]*stanzaInterface)
-	physicalStanzas := make(map[string]*stanzaInterface)
-	vlanStanzas := make(map[string]*stanzaInterface)
+	interfaceMap := createInterfaces(stanzas)
+	linkAncestors(interfaceMap)
+	markConfigDepths(interfaceMap)
+
+	interfaces := make([]InterfaceGenerator, 0, len(interfaceMap))
+	for _, iface := range interfaceMap {
+		interfaces = append(interfaces, iface)
+	}
+
+	return interfaces
+}
+
+func createInterfaces(stanzas []*stanzaInterface) map[string]networkInterface {
+	interfaceMap := make(map[string]networkInterface)
 	for _, iface := range stanzas {
 		switch iface.kind {
 		case interfaceBond:
-			bondStanzas[iface.name] = iface
-		case interfacePhysical:
-			physicalStanzas[iface.name] = iface
-		case interfaceVLAN:
-			vlanStanzas[iface.name] = iface
+			bondOptions := make(map[string]string)
+			for _, k := range []string{"mode", "miimon", "lacp-rate"} {
+				if v, ok := iface.options["bond-"+k]; ok && len(v) > 0 {
+					bondOptions[k] = v[0]
+				}
+			}
+			interfaceMap[iface.name] = &bondInterface{
+				logicalInterface{
+					name:     iface.name,
+					config:   iface.configMethod,
+					children: []networkInterface{},
+				},
+				iface.options["bond-slaves"],
+				bondOptions,
+			}
+			for _, slave := range iface.options["bond-slaves"] {
+				if _, ok := interfaceMap[slave]; !ok {
+					interfaceMap[slave] = &physicalInterface{
+						logicalInterface{
+							name:     slave,
+							config:   configMethodManual{},
+							children: []networkInterface{},
+						},
+					}
 				}
 			}
 
-	physicals := make(map[string]*physicalInterface)
-	for _, p := range physicalStanzas {
-		if _, ok := p.configMethod.(configMethodLoopback); ok {
+		case interfacePhysical:
+			if _, ok := iface.configMethod.(configMethodLoopback); ok {
 				continue
 			}
-		physicals[p.name] = &physicalInterface{
+			interfaceMap[iface.name] = &physicalInterface{
 				logicalInterface{
-				name:     p.name,
-				config:   p.configMethod,
-				children: []InterfaceGenerator{},
+					name:     iface.name,
+					config:   iface.configMethod,
+					children: []networkInterface{},
 				},
 			}
-	}
 
-	bonds := make(map[string]*bondInterface)
-	for _, b := range bondStanzas {
-		bonds[b.name] = &bondInterface{
-			logicalInterface{
-				name:     b.name,
-				config:   b.configMethod,
-				children: []InterfaceGenerator{},
-			},
-			b.options["slaves"],
-		}
-	}
-
-	vlans := make(map[string]*vlanInterface)
-	for _, v := range vlanStanzas {
+		case interfaceVLAN:
 			var rawDevice string
-		id, _ := strconv.Atoi(v.options["id"][0])
-		if device := v.options["raw_device"]; len(device) == 1 {
+			id, _ := strconv.Atoi(iface.options["id"][0])
+			if device := iface.options["raw_device"]; len(device) == 1 {
 				rawDevice = device[0]
-		}
-		vlans[v.name] = &vlanInterface{
+				if _, ok := interfaceMap[rawDevice]; !ok {
+					interfaceMap[rawDevice] = &physicalInterface{
 						logicalInterface{
-				name:     v.name,
-				config:   v.configMethod,
-				children: []InterfaceGenerator{},
+							name:     rawDevice,
+							config:   configMethodManual{},
+							children: []networkInterface{},
+						},
+					}
+				}
+			}
+			interfaceMap[iface.name] = &vlanInterface{
+				logicalInterface{
+					name:     iface.name,
+					config:   iface.configMethod,
+					children: []networkInterface{},
 				},
 				id,
 				rawDevice,
 			}
 		}
-
-	for _, vlan := range vlans {
-		if physical, ok := physicals[vlan.rawDevice]; ok {
-			physical.children = append(physical.children, vlan)
 	}
-		if bond, ok := bonds[vlan.rawDevice]; ok {
-			bond.children = append(bond.children, vlan)
-		}
-	}
-
-	for _, bond := range bonds {
-		for _, slave := range bond.slaves {
-			if physical, ok := physicals[slave]; ok {
-				physical.children = append(physical.children, bond)
-			}
-			if pBond, ok := bonds[slave]; ok {
-				pBond.children = append(pBond.children, bond)
-			}
-		}
-	}
-
-	interfaces := make([]InterfaceGenerator, 0, len(physicals)+len(bonds)+len(vlans))
-	for _, physical := range physicals {
-		interfaces = append(interfaces, physical)
-	}
-	for _, bond := range bonds {
-		interfaces = append(interfaces, bond)
-	}
-	for _, vlan := range vlans {
-		interfaces = append(interfaces, vlan)
-	}
-
-	return interfaces
+	return interfaceMap
+}
+
+func linkAncestors(interfaceMap map[string]networkInterface) {
+	for _, iface := range interfaceMap {
+		switch i := iface.(type) {
+		case *vlanInterface:
+			if parent, ok := interfaceMap[i.rawDevice]; ok {
+				switch p := parent.(type) {
+				case *physicalInterface:
+					p.children = append(p.children, iface)
+				case *bondInterface:
+					p.children = append(p.children, iface)
+				}
+			}
+		case *bondInterface:
+			for _, slave := range i.slaves {
+				if parent, ok := interfaceMap[slave]; ok {
+					switch p := parent.(type) {
+					case *physicalInterface:
+						p.children = append(p.children, iface)
+					case *bondInterface:
+						p.children = append(p.children, iface)
+					}
+				}
+			}
+		}
+	}
+}
+
+func markConfigDepths(interfaceMap map[string]networkInterface) {
+	rootInterfaceMap := make(map[string]networkInterface)
+	for k, v := range interfaceMap {
+		rootInterfaceMap[k] = v
+	}
+
+	for _, iface := range interfaceMap {
+		for _, child := range iface.Children() {
+			delete(rootInterfaceMap, child.Name())
+		}
+	}
+	for _, iface := range rootInterfaceMap {
+		setDepth(iface)
+	}
+}
+
+func setDepth(iface networkInterface) int {
+	maxDepth := 0
+	for _, child := range iface.Children() {
+		if depth := setDepth(child); depth > maxDepth {
+			maxDepth = depth
+		}
+	}
+	iface.setConfigDepth(maxDepth)
+	return (maxDepth + 1)
 }

network/interface_test.go

@@ -30,12 +30,13 @@ func TestPhysicalInterfaceLink(t *testing.T) {
 func TestPhysicalInterfaceNetwork(t *testing.T) {
 	p := physicalInterface{logicalInterface{
 		name: "testname",
-		children: []InterfaceGenerator{
+		children: []networkInterface{
 			&bondInterface{
 				logicalInterface{
 					name: "testbond1",
 				},
 				nil,
+				nil,
 			},
 			&vlanInterface{
 				logicalInterface{
@@ -67,14 +68,14 @@ VLAN=testvlan2
 }
 
 func TestBondInterfaceName(t *testing.T) {
-	b := bondInterface{logicalInterface{name: "testname"}, nil}
+	b := bondInterface{logicalInterface{name: "testname"}, nil, nil}
 	if b.Name() != "testname" {
 		t.FailNow()
 	}
 }
 
 func TestBondInterfaceNetdev(t *testing.T) {
-	b := bondInterface{logicalInterface{name: "testname"}, nil}
+	b := bondInterface{logicalInterface{name: "testname"}, nil, nil}
 	netdev := `[NetDev]
 Kind=bond
 Name=testname
@@ -96,12 +97,13 @@ func TestBondInterfaceNetwork(t *testing.T) {
 		logicalInterface{
 			name:   "testname",
 			config: configMethodDHCP{},
-			children: []InterfaceGenerator{
+			children: []networkInterface{
 				&bondInterface{
 					logicalInterface{
 						name: "testbond1",
 					},
 					nil,
+					nil,
 				},
 				&vlanInterface{
 					logicalInterface{
@@ -120,6 +122,7 @@ func TestBondInterfaceNetwork(t *testing.T) {
 			},
 		},
 		nil,
+		nil,
 	}
 	network := `[Match]
 Name=testname
@@ -143,16 +146,26 @@ func TestVLANInterfaceName(t *testing.T) {
 }
 
 func TestVLANInterfaceNetdev(t *testing.T) {
-	v := vlanInterface{logicalInterface{name: "testname"}, 1, ""}
-	netdev := `[NetDev]
-Kind=vlan
-Name=testname
-
-[VLAN]
-Id=1
-`
-	if v.Netdev() != netdev {
-		t.FailNow()
+	for _, tt := range []struct {
+		i vlanInterface
+		l string
+	}{
+		{
+			vlanInterface{logicalInterface{name: "testname"}, 1, ""},
+			"[NetDev]\nKind=vlan\nName=testname\n\n[VLAN]\nId=1\n",
+		},
+		{
+			vlanInterface{logicalInterface{name: "testname", config: configMethodStatic{hwaddress: net.HardwareAddr([]byte{0, 1, 2, 3, 4, 5})}}, 1, ""},
+			"[NetDev]\nKind=vlan\nName=testname\nMACAddress=00:01:02:03:04:05\n\n[VLAN]\nId=1\n",
+		},
+		{
+			vlanInterface{logicalInterface{name: "testname", config: configMethodDHCP{hwaddress: net.HardwareAddr([]byte{0, 1, 2, 3, 4, 5})}}, 1, ""},
+			"[NetDev]\nKind=vlan\nName=testname\nMACAddress=00:01:02:03:04:05\n\n[VLAN]\nId=1\n",
+		},
+	} {
+		if tt.i.Netdev() != tt.l {
+			t.Fatalf("bad netdev config (%q): got %q, want %q", tt.i, tt.i.Netdev(), tt.l)
+		}
 	}
 }
 
@@ -208,6 +221,61 @@ Gateway=1.2.3.4
 	}
 }
 
+func TestType(t *testing.T) {
+	for _, tt := range []struct {
+		i InterfaceGenerator
+		t string
+	}{
+		{
+			i: &physicalInterface{},
+			t: "physical",
+		},
+		{
+			i: &vlanInterface{},
+			t: "vlan",
+		},
+		{
+			i: &bondInterface{},
+			t: "bond",
+		},
+	} {
+		if tp := tt.i.Type(); tp != tt.t {
+			t.Fatalf("bad type (%q): got %s, want %s", tt.i, tp, tt.t)
+		}
+	}
+}
+
+func TestModprobeParams(t *testing.T) {
+	for _, tt := range []struct {
+		i InterfaceGenerator
+		p string
+	}{
+		{
+			i: &physicalInterface{},
+			p: "",
+		},
+		{
+			i: &vlanInterface{},
+			p: "",
+		},
+		{
+			i: &bondInterface{
+				logicalInterface{},
+				nil,
+				map[string]string{
+					"a": "1",
+					"b": "2",
+				},
+			},
+			p: "a=1 b=2",
+		},
+	} {
+		if p := tt.i.ModprobeParams(); p != tt.p {
+			t.Fatalf("bad params (%q): got %s, want %s", tt.i, p, tt.p)
+		}
+	}
+}
+
 func TestBuildInterfacesLo(t *testing.T) {
 	stanzas := []*stanzaInterface{
 		&stanzaInterface{
@@ -224,6 +292,81 @@ func TestBuildInterfacesLo(t *testing.T) {
 	}
 }
 
+func TestBuildInterfacesBlindBond(t *testing.T) {
+	stanzas := []*stanzaInterface{
+		{
+			name:         "bond0",
+			kind:         interfaceBond,
+			auto:         false,
+			configMethod: configMethodManual{},
+			options: map[string][]string{
+				"bond-slaves": []string{"eth0"},
+			},
+		},
+	}
+	interfaces := buildInterfaces(stanzas)
+	bond0 := &bondInterface{
+		logicalInterface{
+			name:        "bond0",
+			config:      configMethodManual{},
+			children:    []networkInterface{},
+			configDepth: 0,
+		},
+		[]string{"eth0"},
+		map[string]string{},
+	}
+	eth0 := &physicalInterface{
+		logicalInterface{
+			name:        "eth0",
+			config:      configMethodManual{},
+			children:    []networkInterface{bond0},
+			configDepth: 1,
+		},
+	}
+	expect := []InterfaceGenerator{bond0, eth0}
+	if !reflect.DeepEqual(interfaces, expect) {
+		t.FailNow()
+	}
+}
+
+func TestBuildInterfacesBlindVLAN(t *testing.T) {
+	stanzas := []*stanzaInterface{
+		{
+			name:         "vlan0",
+			kind:         interfaceVLAN,
+			auto:         false,
+			configMethod: configMethodManual{},
+			options: map[string][]string{
+				"id":         []string{"0"},
+				"raw_device": []string{"eth0"},
+			},
+		},
+	}
+	interfaces := buildInterfaces(stanzas)
+	vlan0 := &vlanInterface{
+		logicalInterface{
+			name:        "vlan0",
+			config:      configMethodManual{},
+			children:    []networkInterface{},
+			configDepth: 0,
+		},
+		0,
+		"eth0",
+	}
+	eth0 := &physicalInterface{
+		logicalInterface{
+			name:        "eth0",
+			config:      configMethodManual{},
+			children:    []networkInterface{vlan0},
+			configDepth: 1,
+		},
+	}
+	expect := []InterfaceGenerator{eth0, vlan0}
+	if !reflect.DeepEqual(interfaces, expect) {
+		t.FailNow()
+	}
+}
+
 func TestBuildInterfaces(t *testing.T) {
 	stanzas := []*stanzaInterface{
 		&stanzaInterface{
@@ -239,7 +382,9 @@ func TestBuildInterfaces(t *testing.T) {
 			auto:         false,
 			configMethod: configMethodManual{},
 			options: map[string][]string{
-				"slaves": []string{"eth0"},
+				"bond-slaves": []string{"eth0"},
+				"bond-mode":   []string{"4"},
+				"bond-miimon": []string{"100"},
 			},
 		},
 		&stanzaInterface{
@@ -248,7 +393,7 @@ func TestBuildInterfaces(t *testing.T) {
 			auto:         false,
 			configMethod: configMethodManual{},
 			options: map[string][]string{
-				"slaves": []string{"bond0"},
+				"bond-slaves": []string{"bond0"},
 			},
 		},
 		&stanzaInterface{
@@ -277,7 +422,8 @@ func TestBuildInterfaces(t *testing.T) {
 		logicalInterface{
 			name:        "vlan1",
 			config:      configMethodManual{},
-			children: []InterfaceGenerator{},
+			children:    []networkInterface{},
+			configDepth: 0,
 		},
 		1,
 		"bond0",
@@ -286,7 +432,8 @@ func TestBuildInterfaces(t *testing.T) {
 		logicalInterface{
 			name:        "vlan0",
 			config:      configMethodManual{},
-			children: []InterfaceGenerator{},
+			children:    []networkInterface{},
+			configDepth: 0,
 		},
 		0,
 		"eth0",
@@ -295,23 +442,31 @@ func TestBuildInterfaces(t *testing.T) {
 		logicalInterface{
 			name:        "bond1",
 			config:      configMethodManual{},
-			children: []InterfaceGenerator{},
+			children:    []networkInterface{},
+			configDepth: 0,
 		},
 		[]string{"bond0"},
+		map[string]string{},
 	}
 	bond0 := &bondInterface{
 		logicalInterface{
 			name:        "bond0",
 			config:      configMethodManual{},
-			children: []InterfaceGenerator{vlan1, bond1},
+			children:    []networkInterface{bond1, vlan1},
+			configDepth: 1,
 		},
 		[]string{"eth0"},
+		map[string]string{
+			"mode":   "4",
+			"miimon": "100",
+		},
 	}
 	eth0 := &physicalInterface{
 		logicalInterface{
 			name:        "eth0",
 			config:      configMethodManual{},
-			children: []InterfaceGenerator{vlan0, bond0},
+			children:    []networkInterface{bond0, vlan0},
+			configDepth: 2,
 		},
 	}
 	expect := []InterfaceGenerator{eth0, bond0, bond1, vlan0, vlan1}
@@ -319,3 +474,19 @@ func TestBuildInterfaces(t *testing.T) {
 		t.FailNow()
 	}
 }
+
+func TestFilename(t *testing.T) {
+	for _, tt := range []struct {
+		i logicalInterface
+		f string
+	}{
+		{logicalInterface{name: "iface", configDepth: 0}, "00-iface"},
+		{logicalInterface{name: "iface", configDepth: 9}, "09-iface"},
+		{logicalInterface{name: "iface", configDepth: 10}, "0a-iface"},
+		{logicalInterface{name: "iface", configDepth: 53}, "35-iface"},
+	} {
+		if tt.i.Filename() != tt.f {
+			t.Fatalf("bad filename (%q): got %q, want %q", tt.i, tt.i.Filename(), tt.f)
+		}
+	}
+}

network/stanza.go

@@ -40,13 +40,16 @@ type configMethodStatic struct {
 	address     net.IPNet
 	nameservers []net.IP
 	routes      []route
+	hwaddress   net.HardwareAddr
 }
 
 type configMethodLoopback struct{}
 
 type configMethodManual struct{}
 
-type configMethodDHCP struct{}
+type configMethodDHCP struct {
+	hwaddress net.HardwareAddr
+}
 
 func parseStanzas(lines []string) (stanzas []stanza, err error) {
 	rawStanzas, err := splitStanzas(lines)
@@ -96,7 +99,7 @@ func splitStanzas(lines []string) ([][]string, error) {
 		} else if curStanza != nil {
 			curStanza = append(curStanza, line)
 		} else {
-			return nil, fmt.Errorf("missing stanza start '%s'", line)
+			return nil, fmt.Errorf("missing stanza start %q", line)
 		}
 	}
 
@@ -142,7 +145,7 @@ func parseStanza(rawStanza []string) (stanza, error) {
 	case "iface":
 		return parseInterfaceStanza(attributes, rawStanza[1:])
 	default:
-		return nil, fmt.Errorf("unknown stanza '%s'", kind)
+		return nil, fmt.Errorf("unknown stanza %q", kind)
 	}
 }
 
@@ -204,7 +207,7 @@ func parseInterfaceStanza(attributes []string, options []string) (*stanzaInterfa
 			}
 		}
 		if config.address.IP == nil || config.address.Mask == nil {
-			return nil, fmt.Errorf("malformed static network config for '%s'", iface)
+			return nil, fmt.Errorf("malformed static network config for %q", iface)
 		}
 		if gateways, ok := optionMap["gateway"]; ok {
 			if len(gateways) == 1 {
@@ -217,6 +220,11 @@ func parseInterfaceStanza(attributes []string, options []string) (*stanzaInterfa
 				})
 			}
 		}
+		if hwaddress, err := parseHwaddress(optionMap, iface); err == nil {
+			config.hwaddress = hwaddress
+		} else {
+			return nil, err
+		}
 		for _, nameserver := range optionMap["dns-nameservers"] {
 			config.nameservers = append(config.nameservers, net.ParseIP(nameserver))
 		}
@@ -245,9 +253,15 @@ func parseInterfaceStanza(attributes []string, options []string) (*stanzaInterfa
 	case "manual":
 		conf = configMethodManual{}
 	case "dhcp":
-		conf = configMethodDHCP{}
+		config := configMethodDHCP{}
+		if hwaddress, err := parseHwaddress(optionMap, iface); err == nil {
+			config.hwaddress = hwaddress
+		} else {
+			return nil, err
+		}
+		conf = config
 	default:
-		return nil, fmt.Errorf("invalid config method '%s'", confMethod)
+		return nil, fmt.Errorf("invalid config method %q", confMethod)
 	}
 
 	if _, ok := optionMap["vlan_raw_device"]; ok {
@@ -265,8 +279,20 @@ func parseInterfaceStanza(attributes []string, options []string) (*stanzaInterfa
 	return parsePhysicalStanza(iface, conf, attributes, optionMap)
 }
 
+func parseHwaddress(options map[string][]string, iface string) (net.HardwareAddr, error) {
+	if hwaddress, ok := options["hwaddress"]; ok && len(hwaddress) == 2 {
+		switch hwaddress[0] {
+		case "ether":
+			if address, err := net.ParseMAC(hwaddress[1]); err == nil {
+				return address, nil
+			}
+			return nil, fmt.Errorf("malformed hwaddress option for %q", iface)
+		}
+	}
+	return nil, nil
+}
+
 func parseBondStanza(iface string, conf configMethod, attributes []string, options map[string][]string) (*stanzaInterface, error) {
-	options["slaves"] = options["bond-slaves"]
 	return &stanzaInterface{name: iface, kind: interfaceBond, configMethod: conf, options: options}, nil
 }
 
@@ -282,11 +308,11 @@ func parseVLANStanza(iface string, conf configMethod, attributes []string, optio
 	} else if strings.HasPrefix(iface, "vlan") {
 		id = strings.TrimPrefix(iface, "vlan")
 	} else {
-		return nil, fmt.Errorf("malformed vlan name %s", iface)
+		return nil, fmt.Errorf("malformed vlan name %q", iface)
 	}
 
 	if _, err := strconv.Atoi(id); err != nil {
-		return nil, fmt.Errorf("malformed vlan name %s", iface)
+		return nil, fmt.Errorf("malformed vlan name %q", iface)
 	}
 	options["id"] = []string{id}
 	options["raw_device"] = options["vlan_raw_device"]

network/stanza_test.go

@@ -42,6 +42,8 @@ func TestBadParseInterfaceStanza(t *testing.T) {
 		{[]string{"eth", "inet", "static"}, []string{"netmask 255.255.255.0"}, "malformed static network config"},
 		{[]string{"eth", "inet", "static"}, []string{"address invalid", "netmask 255.255.255.0"}, "malformed static network config"},
 		{[]string{"eth", "inet", "static"}, []string{"address 192.168.1.100", "netmask invalid"}, "malformed static network config"},
+		{[]string{"eth", "inet", "static"}, []string{"address 192.168.1.100", "netmask 255.255.255.0", "hwaddress ether NotAnAddress"}, "malformed hwaddress option"},
+		{[]string{"eth", "inet", "dhcp"}, []string{"hwaddress ether NotAnAddress"}, "malformed hwaddress option"},
 	} {
 		_, err := parseInterfaceStanza(tt.in, tt.opts)
 		if err == nil || !strings.HasPrefix(err.Error(), tt.e) {
@@ -127,7 +129,7 @@ func TestParseBondStanzaNoSlaves(t *testing.T) {
 	if err != nil {
 		t.FailNow()
 	}
-	if bond.options["slaves"] != nil {
+	if bond.options["bond-slaves"] != nil {
 		t.FailNow()
 	}
 }
@@ -150,9 +152,6 @@ func TestParseBondStanza(t *testing.T) {
 	if bond.configMethod != conf {
 		t.FailNow()
 	}
-	if !reflect.DeepEqual(bond.options["slaves"], options["bond-slaves"]) {
-		t.FailNow()
-	}
 }
 
 func TestParsePhysicalStanza(t *testing.T) {
@@ -407,7 +406,46 @@ func TestParseInterfaceStanzaOptions(t *testing.T) {
 	}
 }
 
-func TestParseInterfaceStazaBond(t *testing.T) {
+func TestParseInterfaceStanzaHwaddress(t *testing.T) {
+	for _, tt := range []struct {
+		attr []string
+		opt  []string
+		hw   net.HardwareAddr
+	}{
+		{
+			[]string{"mybond", "inet", "dhcp"},
+			[]string{},
+			nil,
+		},
+		{
+			[]string{"mybond", "inet", "dhcp"},
+			[]string{"hwaddress ether 00:01:02:03:04:05"},
+			net.HardwareAddr([]byte{0, 1, 2, 3, 4, 5}),
+		},
+		{
+			[]string{"mybond", "inet", "static"},
+			[]string{"hwaddress ether 00:01:02:03:04:05", "address 192.168.1.100", "netmask 255.255.255.0"},
+			net.HardwareAddr([]byte{0, 1, 2, 3, 4, 5}),
+		},
+	} {
+		iface, err := parseInterfaceStanza(tt.attr, tt.opt)
+		if err != nil {
+			t.Fatalf("error in parseInterfaceStanza (%q, %q): %q", tt.attr, tt.opt, err)
+		}
+		switch c := iface.configMethod.(type) {
+		case configMethodStatic:
+			if !reflect.DeepEqual(c.hwaddress, tt.hw) {
+				t.Fatalf("bad hwaddress (%q, %q): got %q, want %q", tt.attr, tt.opt, c.hwaddress, tt.hw)
+			}
+		case configMethodDHCP:
+			if !reflect.DeepEqual(c.hwaddress, tt.hw) {
+				t.Fatalf("bad hwaddress (%q, %q): got %q, want %q", tt.attr, tt.opt, c.hwaddress, tt.hw)
+			}
+		}
+	}
+}
+
+func TestParseInterfaceStanzaBond(t *testing.T) {
 	iface, err := parseInterfaceStanza([]string{"mybond", "inet", "manual"}, []string{"bond-slaves eth"})
 	if err != nil {
 		t.FailNow()
@@ -417,7 +455,7 @@ func TestParseInterfaceStazaBond(t *testing.T) {
 	}
 }
 
-func TestParseInterfaceStazaVLANName(t *testing.T) {
+func TestParseInterfaceStanzaVLANName(t *testing.T) {
 	iface, err := parseInterfaceStanza([]string{"eth0.1", "inet", "manual"}, nil)
 	if err != nil {
 		t.FailNow()
@@ -427,7 +465,7 @@ func TestParseInterfaceStazaVLANName(t *testing.T) {
 	}
 }
 
-func TestParseInterfaceStazaVLANOption(t *testing.T) {
+func TestParseInterfaceStanzaVLANOption(t *testing.T) {
 	iface, err := parseInterfaceStanza([]string{"vlan1", "inet", "manual"}, []string{"vlan_raw_device eth"})
 	if err != nil {
 		t.FailNow()

pkg/http_client.go

@@ -18,6 +18,28 @@ const (
 	HTTP_4xx = 4
 )
 
+type Err error
+
+type ErrTimeout struct {
+	Err
+}
+
+type ErrNotFound struct {
+	Err
+}
+
+type ErrInvalid struct {
+	Err
+}
+
+type ErrServer struct {
+	Err
+}
+
+type ErrNetwork struct {
+	Err
+}
+
 type HttpClient struct {
 	// Maximum exp backoff duration. Defaults to 5 seconds
 	MaxBackoff time.Duration
@@ -31,18 +53,42 @@ type HttpClient struct {
 
 	// Whether or not to skip TLS verification. Defaults to false
 	SkipTLS bool
+
+	client *http.Client
 }
 
 func NewHttpClient() *HttpClient {
-	return &HttpClient{
+	hc := &HttpClient{
 		MaxBackoff: time.Second * 5,
 		MaxRetries: 15,
 		Timeout:    time.Duration(2) * time.Second,
 		SkipTLS:    false,
 	}
+
+	// We need to create our own client in order to add timeout support.
+	// TODO(c4milo) Replace it once Go 1.3 is officially used by CoreOS
+	// More info: https://code.google.com/p/go/source/detail?r=ada6f2d5f99f
+	hc.client = &http.Client{
+		Transport: &http.Transport{
+			TLSClientConfig: &tls.Config{
+				InsecureSkipVerify: hc.SkipTLS,
+			},
+			Dial: func(network, addr string) (net.Conn, error) {
+				deadline := time.Now().Add(hc.Timeout)
+				c, err := net.DialTimeout(network, addr, hc.Timeout)
+				if err != nil {
+					return nil, err
+				}
+				c.SetDeadline(deadline)
+				return c, nil
+			},
+		},
+	}
+
+	return hc
 }
 
-func expBackoff(interval, max time.Duration) time.Duration {
+func ExpBackoff(interval, max time.Duration) time.Duration {
 	interval = interval * 2
 	if interval > max {
 		interval = max
@@ -50,74 +96,61 @@ func expBackoff(interval, max time.Duration) time.Duration {
 	return interval
 }
 
-// Fetches a given URL with support for exponential backoff and maximum retries
-func (h *HttpClient) Get(rawurl string) ([]byte, error) {
+// GetRetry fetches a given URL with support for exponential backoff and maximum retries
+func (h *HttpClient) GetRetry(rawurl string) ([]byte, error) {
 	if rawurl == "" {
-		return nil, errors.New("URL is empty. Skipping.")
+		return nil, ErrInvalid{errors.New("URL is empty. Skipping.")}
 	}
 
 	url, err := neturl.Parse(rawurl)
 	if err != nil {
-		return nil, err
+		return nil, ErrInvalid{err}
 	}
 
 	// Unfortunately, url.Parse is too generic to throw errors if a URL does not
 	// have a valid HTTP scheme. So, we have to do this extra validation
 	if !strings.HasPrefix(url.Scheme, "http") {
-		return nil, fmt.Errorf("URL %s does not have a valid HTTP scheme. Skipping.", rawurl)
+		return nil, ErrInvalid{fmt.Errorf("URL %s does not have a valid HTTP scheme. Skipping.", rawurl)}
 	}
 
 	dataURL := url.String()
 
-	// We need to create our own client in order to add timeout support.
-	// TODO(c4milo) Replace it once Go 1.3 is officially used by CoreOS
-	// More info: https://code.google.com/p/go/source/detail?r=ada6f2d5f99f
-	transport := &http.Transport{
-		TLSClientConfig: &tls.Config{
-			InsecureSkipVerify: h.SkipTLS,
-		},
-		Dial: func(network, addr string) (net.Conn, error) {
-			deadline := time.Now().Add(h.Timeout)
-			c, err := net.DialTimeout(network, addr, h.Timeout)
-			if err != nil {
-				return nil, err
-			}
-			c.SetDeadline(deadline)
-			return c, nil
-		},
-	}
-
-	client := &http.Client{
-		Transport: transport,
-	}
-
 	duration := 50 * time.Millisecond
 	for retry := 1; retry <= h.MaxRetries; retry++ {
 		log.Printf("Fetching data from %s. Attempt #%d", dataURL, retry)
 
-		resp, err := client.Get(dataURL)
-
-		if err == nil {
-			defer resp.Body.Close()
-			status := resp.StatusCode / 100
-
-			if status == HTTP_2xx {
-				return ioutil.ReadAll(resp.Body)
+		data, err := h.Get(dataURL)
+		switch err.(type) {
+		case ErrNetwork:
+			log.Printf(err.Error())
+		case ErrServer:
+			log.Printf(err.Error())
+		case ErrNotFound:
+			return data, err
+		default:
+			return data, err
 		}
 
-			if status == HTTP_4xx {
-				return nil, fmt.Errorf("Not found. HTTP status code: %d", resp.StatusCode)
-			}
-
-			log.Printf("Server error. HTTP status code: %d", resp.StatusCode)
-		} else {
-			log.Printf("Unable to fetch data: %s", err.Error())
-		}
-
-		duration = expBackoff(duration, h.MaxBackoff)
+		duration = ExpBackoff(duration, h.MaxBackoff)
 		log.Printf("Sleeping for %v...", duration)
 		time.Sleep(duration)
 	}
 
-	return nil, fmt.Errorf("Unable to fetch data. Maximum retries reached: %d", h.MaxRetries)
+	return nil, ErrTimeout{fmt.Errorf("Unable to fetch data. Maximum retries reached: %d", h.MaxRetries)}
+}
+
+func (h *HttpClient) Get(dataURL string) ([]byte, error) {
+	if resp, err := h.client.Get(dataURL); err == nil {
+		defer resp.Body.Close()
+		switch resp.StatusCode / 100 {
+		case HTTP_2xx:
+			return ioutil.ReadAll(resp.Body)
+		case HTTP_4xx:
+			return nil, ErrNotFound{fmt.Errorf("Not found. HTTP status code: %d", resp.StatusCode)}
+		default:
+			return nil, ErrServer{fmt.Errorf("Server error. HTTP status code: %d", resp.StatusCode)}
+		}
+	} else {
+		return nil, ErrNetwork{fmt.Errorf("Unable to fetch data: %s", err.Error())}
+	}
 }

pkg/http_client_test.go

@@ -14,7 +14,7 @@ func TestExpBackoff(t *testing.T) {
 	duration := time.Millisecond
 	max := time.Hour
 	for i := 0; i < math.MaxUint16; i++ {
-		duration = expBackoff(duration, max)
+		duration = ExpBackoff(duration, max)
 		if duration < 0 {
 			t.Fatalf("duration too small: %v %v", duration, i)
 		}
@@ -51,7 +51,7 @@ func TestGetURLExpBackOff(t *testing.T) {
 		ts := httptest.NewServer(mux)
 		defer ts.Close()
 
-		data, err := client.Get(ts.URL)
+		data, err := client.GetRetry(ts.URL)
 		if err != nil {
 			t.Errorf("Test case %d produced error: %v", i, err)
 		}
@@ -76,7 +76,7 @@ func TestGetURL4xx(t *testing.T) {
 	}))
 	defer ts.Close()
 
-	_, err := client.Get(ts.URL)
+	_, err := client.GetRetry(ts.URL)
 	if err == nil {
 		t.Errorf("Incorrect result\ngot:  %s\nwant: %s", err.Error(), "Not found. HTTP status code: 404")
 	}
@@ -107,7 +107,7 @@ coreos:
 	}))
 	defer ts.Close()
 
-	data, err := client.Get(ts.URL)
+	data, err := client.GetRetry(ts.URL)
 	if err != nil {
 		t.Errorf("Incorrect result\ngot:  %v\nwant: %v", err, nil)
 	}
@@ -132,7 +132,7 @@ func TestGetMalformedURL(t *testing.T) {
 	}
 
 	for _, test := range tests {
-		_, err := client.Get(test.url)
+		_, err := client.GetRetry(test.url)
 		if err == nil || err.Error() != test.want {
 			t.Errorf("Incorrect result\ngot:  %v\nwant: %v", err, test.want)
 		}

system/env_file.go

@@ -0,0 +1,89 @@
+package system
+
+import (
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path"
+	"regexp"
+)
+
+type EnvFile struct {
+	Vars map[string]string
+	// mask File.Content, it shouldn't be used.
+	Content interface{} `json:"-" yaml:"-"`
+	*File
+}
+
+// only allow sh compatible identifiers
+var validKey = regexp.MustCompile(`^[a-zA-Z0-9_]+$`)
+
+// match each line, optionally capturing valid identifiers, discarding dos line endings
+var lineLexer = regexp.MustCompile(`(?m)^((?:([a-zA-Z0-9_]+)=)?.*?)\r?\n`)
+
+// mergeEnvContents: Update the existing file contents with new values,
+// preserving variable ordering and all content this code doesn't understand.
+// All new values are appended to the bottom of the old.
+func mergeEnvContents(old []byte, pending map[string]string) []byte {
+	var buf bytes.Buffer
+	var match [][]byte
+
+	// it is awkward for the regex to handle a missing newline gracefully
+	if len(old) != 0 && !bytes.HasSuffix(old, []byte{'\n'}) {
+		old = append(old, byte('\n'))
+	}
+
+	for _, match = range lineLexer.FindAllSubmatch(old, -1) {
+		key := string(match[2])
+		if value, ok := pending[key]; ok {
+			fmt.Fprintf(&buf, "%s=%s\n", key, value)
+			delete(pending, key)
+		} else {
+			fmt.Fprintf(&buf, "%s\n", match[1])
+		}
+	}
+
+	for key, value := range pending {
+		fmt.Fprintf(&buf, "%s=%s\n", key, value)
+	}
+
+	return buf.Bytes()
+}
+
+// WriteEnvFile updates an existing env `KEY=value` formated file with
+// new values provided in EnvFile.Vars; File.Content is ignored.
+// Existing ordering and any unknown formatting such as comments are
+// preserved. If no changes are required the file is untouched.
+func WriteEnvFile(ef *EnvFile, root string) error {
+	// validate new keys, mergeEnvContents uses pending to track writes
+	pending := make(map[string]string, len(ef.Vars))
+	for key, value := range ef.Vars {
+		if !validKey.MatchString(key) {
+			return fmt.Errorf("Invalid name %q for %s", key, ef.Path)
+		}
+		pending[key] = value
+	}
+
+	if len(pending) == 0 {
+		return nil
+	}
+
+	oldContent, err := ioutil.ReadFile(path.Join(root, ef.Path))
+	if err != nil {
+		if os.IsNotExist(err) {
+			oldContent = []byte{}
+		} else {
+			return err
+		}
+	}
+
+	newContent := mergeEnvContents(oldContent, pending)
+	if bytes.Equal(oldContent, newContent) {
+		return nil
+	}
+
+	ef.File.Content = string(newContent)
+	_, err = WriteFile(ef.File, root)
+	return err
+}

system/env_file_test.go

@@ -0,0 +1,426 @@
+package system
+
+import (
+	"io/ioutil"
+	"os"
+	"path"
+	"strings"
+	"syscall"
+	"testing"
+)
+
+const (
+	base          = "# a file\nFOO=base\n\nBAR= hi there\n"
+	baseNoNewline = "# a file\nFOO=base\n\nBAR= hi there"
+	baseDos       = "# a file\r\nFOO=base\r\n\r\nBAR= hi there\r\n"
+	expectUpdate  = "# a file\nFOO=test\n\nBAR= hi there\nNEW=a value\n"
+	expectCreate  = "FOO=test\nNEW=a value\n"
+)
+
+var (
+	valueUpdate = map[string]string{
+		"FOO": "test",
+		"NEW": "a value",
+	}
+	valueNoop = map[string]string{
+		"FOO": "base",
+	}
+	valueEmpty   = map[string]string{}
+	valueInvalid = map[string]string{
+		"FOO-X": "test",
+	}
+)
+
+func TestWriteEnvFileUpdate(t *testing.T) {
+	dir, err := ioutil.TempDir(os.TempDir(), "coreos-cloudinit-")
+	if err != nil {
+		t.Fatalf("Unable to create tempdir: %v", err)
+	}
+	defer os.RemoveAll(dir)
+
+	name := "foo.conf"
+	fullPath := path.Join(dir, name)
+	ioutil.WriteFile(fullPath, []byte(base), 0644)
+
+	oldStat, err := os.Stat(fullPath)
+	if err != nil {
+		t.Fatalf("Unable to stat file: %v", err)
+	}
+
+	ef := EnvFile{
+		File: &File{
+			Path: name,
+		},
+		Vars: valueUpdate,
+	}
+
+	err = WriteEnvFile(&ef, dir)
+	if err != nil {
+		t.Fatalf("WriteFile failed: %v", err)
+	}
+
+	contents, err := ioutil.ReadFile(fullPath)
+	if err != nil {
+		t.Fatalf("Unable to read expected file: %v", err)
+	}
+
+	if string(contents) != expectUpdate {
+		t.Fatalf("File has incorrect contents: %q", contents)
+	}
+
+	newStat, err := os.Stat(fullPath)
+	if err != nil {
+		t.Fatalf("Unable to stat file: %v", err)
+	}
+
+	if oldStat.Sys().(*syscall.Stat_t).Ino == newStat.Sys().(*syscall.Stat_t).Ino {
+		t.Fatalf("File was not replaced: %s", fullPath)
+	}
+}
+
+func TestWriteEnvFileUpdateNoNewline(t *testing.T) {
+	dir, err := ioutil.TempDir(os.TempDir(), "coreos-cloudinit-")
+	if err != nil {
+		t.Fatalf("Unable to create tempdir: %v", err)
+	}
+	defer os.RemoveAll(dir)
+
+	name := "foo.conf"
+	fullPath := path.Join(dir, name)
+	ioutil.WriteFile(fullPath, []byte(baseNoNewline), 0644)
+
+	oldStat, err := os.Stat(fullPath)
+	if err != nil {
+		t.Fatalf("Unable to stat file: %v", err)
+	}
+
+	ef := EnvFile{
+		File: &File{
+			Path: name,
+		},
+		Vars: valueUpdate,
+	}
+
+	err = WriteEnvFile(&ef, dir)
+	if err != nil {
+		t.Fatalf("WriteFile failed: %v", err)
+	}
+
+	contents, err := ioutil.ReadFile(fullPath)
+	if err != nil {
+		t.Fatalf("Unable to read expected file: %v", err)
+	}
+
+	if string(contents) != expectUpdate {
+		t.Fatalf("File has incorrect contents: %q", contents)
+	}
+
+	newStat, err := os.Stat(fullPath)
+	if err != nil {
+		t.Fatalf("Unable to stat file: %v", err)
+	}
+
+	if oldStat.Sys().(*syscall.Stat_t).Ino == newStat.Sys().(*syscall.Stat_t).Ino {
+		t.Fatalf("File was not replaced: %s", fullPath)
+	}
+}
+
+func TestWriteEnvFileCreate(t *testing.T) {
+	dir, err := ioutil.TempDir(os.TempDir(), "coreos-cloudinit-")
+	if err != nil {
+		t.Fatalf("Unable to create tempdir: %v", err)
+	}
+	defer os.RemoveAll(dir)
+
+	name := "foo.conf"
+	fullPath := path.Join(dir, name)
+
+	ef := EnvFile{
+		File: &File{
+			Path: name,
+		},
+		Vars: valueUpdate,
+	}
+
+	err = WriteEnvFile(&ef, dir)
+	if err != nil {
+		t.Fatalf("WriteFile failed: %v", err)
+	}
+
+	contents, err := ioutil.ReadFile(fullPath)
+	if err != nil {
+		t.Fatalf("Unable to read expected file: %v", err)
+	}
+
+	if string(contents) != expectCreate {
+		t.Fatalf("File has incorrect contents: %q", contents)
+	}
+}
+
+func TestWriteEnvFileNoop(t *testing.T) {
+	dir, err := ioutil.TempDir(os.TempDir(), "coreos-cloudinit-")
+	if err != nil {
+		t.Fatalf("Unable to create tempdir: %v", err)
+	}
+	defer os.RemoveAll(dir)
+
+	name := "foo.conf"
+	fullPath := path.Join(dir, name)
+	ioutil.WriteFile(fullPath, []byte(base), 0644)
+
+	oldStat, err := os.Stat(fullPath)
+	if err != nil {
+		t.Fatalf("Unable to stat file: %v", err)
+	}
+
+	ef := EnvFile{
+		File: &File{
+			Path: name,
+		},
+		Vars: valueNoop,
+	}
+
+	err = WriteEnvFile(&ef, dir)
+	if err != nil {
+		t.Fatalf("WriteFile failed: %v", err)
+	}
+
+	contents, err := ioutil.ReadFile(fullPath)
+	if err != nil {
+		t.Fatalf("Unable to read expected file: %v", err)
+	}
+
+	if string(contents) != base {
+		t.Fatalf("File has incorrect contents: %q", contents)
+	}
+
+	newStat, err := os.Stat(fullPath)
+	if err != nil {
+		t.Fatalf("Unable to stat file: %v", err)
+	}
+
+	if oldStat.Sys().(*syscall.Stat_t).Ino != newStat.Sys().(*syscall.Stat_t).Ino {
+		t.Fatalf("File was replaced: %s", fullPath)
+	}
+}
+
+func TestWriteEnvFileUpdateDos(t *testing.T) {
+	dir, err := ioutil.TempDir(os.TempDir(), "coreos-cloudinit-")
+	if err != nil {
+		t.Fatalf("Unable to create tempdir: %v", err)
+	}
+	defer os.RemoveAll(dir)
+
+	name := "foo.conf"
+	fullPath := path.Join(dir, name)
+	ioutil.WriteFile(fullPath, []byte(baseDos), 0644)
+
+	oldStat, err := os.Stat(fullPath)
+	if err != nil {
+		t.Fatalf("Unable to stat file: %v", err)
+	}
+
+	ef := EnvFile{
+		File: &File{
+			Path: name,
+		},
+		Vars: valueUpdate,
+	}
+
+	err = WriteEnvFile(&ef, dir)
+	if err != nil {
+		t.Fatalf("WriteFile failed: %v", err)
+	}
+
+	contents, err := ioutil.ReadFile(fullPath)
+	if err != nil {
+		t.Fatalf("Unable to read expected file: %v", err)
+	}
+
+	if string(contents) != expectUpdate {
+		t.Fatalf("File has incorrect contents: %q", contents)
+	}
+
+	newStat, err := os.Stat(fullPath)
+	if err != nil {
+		t.Fatalf("Unable to stat file: %v", err)
+	}
+
+	if oldStat.Sys().(*syscall.Stat_t).Ino == newStat.Sys().(*syscall.Stat_t).Ino {
+		t.Fatalf("File was not replaced: %s", fullPath)
+	}
+}
+
+// A middle ground noop, values are unchanged but we did have a value.
+// Seems reasonable to rewrite the file in Unix format anyway.
+func TestWriteEnvFileDos2Unix(t *testing.T) {
+	dir, err := ioutil.TempDir(os.TempDir(), "coreos-cloudinit-")
+	if err != nil {
+		t.Fatalf("Unable to create tempdir: %v", err)
+	}
+	defer os.RemoveAll(dir)
+
+	name := "foo.conf"
+	fullPath := path.Join(dir, name)
+	ioutil.WriteFile(fullPath, []byte(baseDos), 0644)
+
+	oldStat, err := os.Stat(fullPath)
+	if err != nil {
+		t.Fatalf("Unable to stat file: %v", err)
+	}
+
+	ef := EnvFile{
+		File: &File{
+			Path: name,
+		},
+		Vars: valueNoop,
+	}
+
+	err = WriteEnvFile(&ef, dir)
+	if err != nil {
+		t.Fatalf("WriteFile failed: %v", err)
+	}
+
+	contents, err := ioutil.ReadFile(fullPath)
+	if err != nil {
+		t.Fatalf("Unable to read expected file: %v", err)
+	}
+
+	if string(contents) != base {
+		t.Fatalf("File has incorrect contents: %q", contents)
+	}
+
+	newStat, err := os.Stat(fullPath)
+	if err != nil {
+		t.Fatalf("Unable to stat file: %v", err)
+	}
+
+	if oldStat.Sys().(*syscall.Stat_t).Ino == newStat.Sys().(*syscall.Stat_t).Ino {
+		t.Fatalf("File was not replaced: %s", fullPath)
+	}
+}
+
+// If it really is a noop (structure is empty) don't even do dos2unix
+func TestWriteEnvFileEmpty(t *testing.T) {
+	dir, err := ioutil.TempDir(os.TempDir(), "coreos-cloudinit-")
+	if err != nil {
+		t.Fatalf("Unable to create tempdir: %v", err)
+	}
+	defer os.RemoveAll(dir)
+
+	name := "foo.conf"
+	fullPath := path.Join(dir, name)
+	ioutil.WriteFile(fullPath, []byte(baseDos), 0644)
+
+	oldStat, err := os.Stat(fullPath)
+	if err != nil {
+		t.Fatalf("Unable to stat file: %v", err)
+	}
+
+	ef := EnvFile{
+		File: &File{
+			Path: name,
+		},
+		Vars: valueEmpty,
+	}
+
+	err = WriteEnvFile(&ef, dir)
+	if err != nil {
+		t.Fatalf("WriteFile failed: %v", err)
+	}
+
+	contents, err := ioutil.ReadFile(fullPath)
+	if err != nil {
+		t.Fatalf("Unable to read expected file: %v", err)
+	}
+
+	if string(contents) != baseDos {
+		t.Fatalf("File has incorrect contents: %q", contents)
+	}
+
+	newStat, err := os.Stat(fullPath)
+	if err != nil {
+		t.Fatalf("Unable to stat file: %v", err)
+	}
+
+	if oldStat.Sys().(*syscall.Stat_t).Ino != newStat.Sys().(*syscall.Stat_t).Ino {
+		t.Fatalf("File was replaced: %s", fullPath)
+	}
+}
+
+// no point in creating empty files
+func TestWriteEnvFileEmptyNoCreate(t *testing.T) {
+	dir, err := ioutil.TempDir(os.TempDir(), "coreos-cloudinit-")
+	if err != nil {
+		t.Fatalf("Unable to create tempdir: %v", err)
+	}
+	defer os.RemoveAll(dir)
+
+	name := "foo.conf"
+	fullPath := path.Join(dir, name)
+
+	ef := EnvFile{
+		File: &File{
+			Path: name,
+		},
+		Vars: valueEmpty,
+	}
+
+	err = WriteEnvFile(&ef, dir)
+	if err != nil {
+		t.Fatalf("WriteFile failed: %v", err)
+	}
+
+	contents, err := ioutil.ReadFile(fullPath)
+	if err == nil {
+		t.Fatalf("File has incorrect contents: %q", contents)
+	} else if !os.IsNotExist(err) {
+		t.Fatalf("Unexpected error while reading file: %v", err)
+	}
+}
+
+func TestWriteEnvFilePermFailure(t *testing.T) {
+	dir, err := ioutil.TempDir(os.TempDir(), "coreos-cloudinit-")
+	if err != nil {
+		t.Fatalf("Unable to create tempdir: %v", err)
+	}
+	defer os.RemoveAll(dir)
+
+	name := "foo.conf"
+	fullPath := path.Join(dir, name)
+	ioutil.WriteFile(fullPath, []byte(base), 0000)
+
+	ef := EnvFile{
+		File: &File{
+			Path: name,
+		},
+		Vars: valueUpdate,
+	}
+
+	err = WriteEnvFile(&ef, dir)
+	if !os.IsPermission(err) {
+		t.Fatalf("Not a pemission denied error: %v", err)
+	}
+}
+
+func TestWriteEnvFileNameFailure(t *testing.T) {
+	dir, err := ioutil.TempDir(os.TempDir(), "coreos-cloudinit-")
+	if err != nil {
+		t.Fatalf("Unable to create tempdir: %v", err)
+	}
+	defer os.RemoveAll(dir)
+
+	name := "foo.conf"
+
+	ef := EnvFile{
+		File: &File{
+			Path: name,
+		},
+		Vars: valueInvalid,
+	}
+
+	err = WriteEnvFile(&ef, dir)
+	if err == nil || !strings.HasPrefix(err.Error(), "Invalid name") {
+		t.Fatalf("Not an invalid name error: %v", err)
+	}
+}

system/networkd.go

@@ -2,10 +2,11 @@ package system
 
 import (
 	"fmt"
-	"io/ioutil"
+	"log"
 	"net"
 	"os/exec"
-	"path"
+	"strings"
+	"time"
 
 	"github.com/coreos/coreos-cloudinit/network"
 	"github.com/coreos/coreos-cloudinit/third_party/github.com/dotcloud/docker/pkg/netlink"
@@ -17,6 +18,13 @@ const (
 
 func RestartNetwork(interfaces []network.InterfaceGenerator) (err error) {
 	defer func() {
+		if e := restartNetworkd(); e != nil {
+			err = e
+			return
+		}
+		// TODO(crawford): Get rid of this once networkd fixes the race
+		// https://bugs.freedesktop.org/show_bug.cgi?id=76077
+		time.Sleep(5 * time.Second)
 		if e := restartNetworkd(); e != nil {
 			err = e
 		}
@@ -26,16 +34,17 @@ func RestartNetwork(interfaces []network.InterfaceGenerator) (err error) {
 		return
 	}
 
-	if err = probe8012q(); err != nil {
+	if err = maybeProbe8012q(interfaces); err != nil {
 		return
 	}
-	return
+	return maybeProbeBonding(interfaces)
 }
 
 func downNetworkInterfaces(interfaces []network.InterfaceGenerator) error {
 	sysInterfaceMap := make(map[string]*net.Interface)
 	if systemInterfaces, err := net.Interfaces(); err == nil {
 		for _, iface := range systemInterfaces {
+			iface := iface
 			sysInterfaceMap[iface.Name] = &iface
 		}
 	} else {
@@ -44,6 +53,7 @@ func downNetworkInterfaces(interfaces []network.InterfaceGenerator) error {
 
 	for _, iface := range interfaces {
 		if systemInterface, ok := sysInterfaceMap[iface.Name()]; ok {
+			log.Printf("Taking down interface %q\n", systemInterface.Name)
 			if err := netlink.NetworkLinkDown(systemInterface); err != nil {
 				fmt.Printf("Error while downing interface %q (%s). Continuing...\n", systemInterface.Name, err)
 			}
@@ -53,26 +63,45 @@ func downNetworkInterfaces(interfaces []network.InterfaceGenerator) error {
 	return nil
 }
 
-func probe8012q() error {
+func maybeProbe8012q(interfaces []network.InterfaceGenerator) error {
+	for _, iface := range interfaces {
+		if iface.Type() == "vlan" {
+			log.Printf("Probing LKM %q (%q)\n", "8021q", "8021q")
 			return exec.Command("modprobe", "8021q").Run()
+		}
+	}
+	return nil
+}
+
+func maybeProbeBonding(interfaces []network.InterfaceGenerator) error {
+	args := []string{"bonding"}
+	for _, iface := range interfaces {
+		if iface.Type() == "bond" {
+			args = append(args, strings.Split(iface.ModprobeParams(), " ")...)
+			break
+		}
+	}
+	log.Printf("Probing LKM %q (%q)\n", "bonding", args)
+	return exec.Command("modprobe", args...).Run()
 }
 
 func restartNetworkd() error {
-	_, err := RunUnitCommand("restart", "systemd-networkd.service")
+	log.Printf("Restarting networkd.service\n")
+	_, err := NewUnitManager("").RunUnitCommand("restart", "systemd-networkd.service")
 	return err
 }
 
 func WriteNetworkdConfigs(interfaces []network.InterfaceGenerator) error {
 	for _, iface := range interfaces {
-		filename := path.Join(runtimeNetworkPath, fmt.Sprintf("%s.netdev", iface.Name()))
+		filename := fmt.Sprintf("%s.netdev", iface.Filename())
 		if err := writeConfig(filename, iface.Netdev()); err != nil {
 			return err
 		}
-		filename = path.Join(runtimeNetworkPath, fmt.Sprintf("%s.link", iface.Name()))
+		filename = fmt.Sprintf("%s.link", iface.Filename())
 		if err := writeConfig(filename, iface.Link()); err != nil {
 			return err
 		}
-		filename = path.Join(runtimeNetworkPath, fmt.Sprintf("%s.network", iface.Name()))
+		filename = fmt.Sprintf("%s.network", iface.Filename())
 		if err := writeConfig(filename, iface.Network()); err != nil {
 			return err
 		}
@@ -84,6 +113,7 @@ func writeConfig(filename string, config string) error {
 	if config == "" {
 		return nil
 	}
-
-	return ioutil.WriteFile(filename, []byte(config), 0444)
+	log.Printf("Writing networkd unit %q\n", filename)
+	_, err := WriteFile(&File{Content: config, Path: filename}, runtimeNetworkPath)
+	return err
 }

system/systemd.go

@@ -13,63 +13,21 @@ import (
 	"github.com/coreos/coreos-cloudinit/third_party/github.com/coreos/go-systemd/dbus"
 )
 
+func NewUnitManager(root string) UnitManager {
+	return &systemd{root}
+}
+
+type systemd struct {
+	root string
+}
+
 // fakeMachineID is placed on non-usr CoreOS images and should
 // never be used as a true MachineID
 const fakeMachineID = "42000000000000000000000000000042"
 
-// Name for drop-in service configuration files created by cloudconfig
-const cloudConfigDropIn = "20-cloudinit.conf"
-
-type Unit struct {
-	Name    string
-	Mask    bool
-	Enable  bool
-	Runtime bool
-	Content string
-	Command string
-
-	// For drop-in units, a cloudinit.conf is generated.
-	// This is currently unbound in YAML (and hence unsettable in cloud-config files)
-	// until the correct behaviour for multiple drop-in units is determined.
-	DropIn bool `yaml:"-"`
-}
-
-func (u *Unit) Type() string {
-	ext := filepath.Ext(u.Name)
-	return strings.TrimLeft(ext, ".")
-}
-
-func (u *Unit) Group() (group string) {
-	t := u.Type()
-	if t == "network" || t == "netdev" || t == "link" {
-		group = "network"
-	} else {
-		group = "system"
-	}
-	return
-}
-
-type Script []byte
-
-// Destination builds the appropriate absolute file path for
-// the Unit. The root argument indicates the effective base
-// directory of the system (similar to a chroot).
-func (u *Unit) Destination(root string) string {
-	dir := "etc"
-	if u.Runtime {
-		dir = "run"
-	}
-
-	if u.DropIn {
-		return path.Join(root, dir, "systemd", u.Group(), fmt.Sprintf("%s.d", u.Name), cloudConfigDropIn)
-	} else {
-		return path.Join(root, dir, "systemd", u.Group(), u.Name)
-	}
-}
-
 // PlaceUnit writes a unit file at the provided destination, creating
 // parent directories as necessary.
-func PlaceUnit(u *Unit, dst string) error {
+func (s *systemd) PlaceUnit(u *Unit, dst string) error {
 	dir := filepath.Dir(dst)
 	if _, err := os.Stat(dir); os.IsNotExist(err) {
 		if err := os.MkdirAll(dir, os.FileMode(0755)); err != nil {
@@ -91,7 +49,7 @@ func PlaceUnit(u *Unit, dst string) error {
 	return nil
 }
 
-func EnableUnitFile(unit string, runtime bool) error {
+func (s *systemd) EnableUnitFile(unit string, runtime bool) error {
 	conn, err := dbus.New()
 	if err != nil {
 		return err
@@ -102,7 +60,7 @@ func EnableUnitFile(unit string, runtime bool) error {
 	return err
 }
 
-func RunUnitCommand(command, unit string) (string, error) {
+func (s *systemd) RunUnitCommand(command, unit string) (string, error) {
 	conn, err := dbus.New()
 	if err != nil {
 		return "", err
@@ -131,7 +89,7 @@ func RunUnitCommand(command, unit string) (string, error) {
 	return fn(unit, "replace")
 }
 
-func DaemonReload() error {
+func (s *systemd) DaemonReload() error {
 	conn, err := dbus.New()
 	if err != nil {
 		return err
@@ -140,6 +98,57 @@ func DaemonReload() error {
 	return conn.Reload()
 }
 
+// MaskUnit masks the given Unit by symlinking its unit file to
+// /dev/null, analogous to `systemctl mask`.
+// N.B.: Unlike `systemctl mask`, this function will *remove any existing unit
+// file at the location*, to ensure that the mask will succeed.
+func (s *systemd) MaskUnit(unit *Unit) error {
+	masked := unit.Destination(s.root)
+	if _, err := os.Stat(masked); os.IsNotExist(err) {
+		if err := os.MkdirAll(path.Dir(masked), os.FileMode(0755)); err != nil {
+			return err
+		}
+	} else if err := os.Remove(masked); err != nil {
+		return err
+	}
+	return os.Symlink("/dev/null", masked)
+}
+
+// UnmaskUnit is analogous to systemd's unit_file_unmask. If the file
+// associated with the given Unit is empty or appears to be a symlink to
+// /dev/null, it is removed.
+func (s *systemd) UnmaskUnit(unit *Unit) error {
+	masked := unit.Destination(s.root)
+	ne, err := nullOrEmpty(masked)
+	if os.IsNotExist(err) {
+		return nil
+	} else if err != nil {
+		return err
+	}
+	if !ne {
+		log.Printf("%s is not null or empty, refusing to unmask", masked)
+		return nil
+	}
+	return os.Remove(masked)
+}
+
+// nullOrEmpty checks whether a given path appears to be an empty regular file
+// or a symlink to /dev/null
+func nullOrEmpty(path string) (bool, error) {
+	fi, err := os.Stat(path)
+	if err != nil {
+		return false, err
+	}
+	m := fi.Mode()
+	if m.IsRegular() && fi.Size() <= 0 {
+		return true, nil
+	}
+	if m&os.ModeCharDevice > 0 {
+		return true, nil
+	}
+	return false, nil
+}
+
 func ExecuteScript(scriptPath string) (string, error) {
 	props := []dbus.Property{
 		dbus.PropDescription("Unit generated and executed by coreos-cloudinit on behalf of user"),
@@ -178,54 +187,3 @@ func MachineID(root string) string {
 
 	return id
 }
-
-// MaskUnit masks the given Unit by symlinking its unit file to
-// /dev/null, analogous to `systemctl mask`.
-// N.B.: Unlike `systemctl mask`, this function will *remove any existing unit
-// file at the location*, to ensure that the mask will succeed.
-func MaskUnit(unit *Unit, root string) error {
-	masked := unit.Destination(root)
-	if _, err := os.Stat(masked); os.IsNotExist(err) {
-		if err := os.MkdirAll(path.Dir(masked), os.FileMode(0755)); err != nil {
-			return err
-		}
-	} else if err := os.Remove(masked); err != nil {
-		return err
-	}
-	return os.Symlink("/dev/null", masked)
-}
-
-// UnmaskUnit is analogous to systemd's unit_file_unmask. If the file
-// associated with the given Unit is empty or appears to be a symlink to
-// /dev/null, it is removed.
-func UnmaskUnit(unit *Unit, root string) error {
-	masked := unit.Destination(root)
-	ne, err := nullOrEmpty(masked)
-	if os.IsNotExist(err) {
-		return nil
-	} else if err != nil {
-		return err
-	}
-	if !ne {
-		log.Printf("%s is not null or empty, refusing to unmask", masked)
-		return nil
-	}
-	return os.Remove(masked)
-}
-
-// nullOrEmpty checks whether a given path appears to be an empty regular file
-// or a symlink to /dev/null
-func nullOrEmpty(path string) (bool, error) {
-	fi, err := os.Stat(path)
-	if err != nil {
-		return false, err
-	}
-	m := fi.Mode()
-	if m.IsRegular() && fi.Size() <= 0 {
-		return true, nil
-	}
-	if m&os.ModeCharDevice > 0 {
-		return true, nil
-	}
-	return false, nil
-}

system/systemd_test.go

@@ -25,13 +25,15 @@ Address=10.209.171.177/19
 	}
 	defer os.RemoveAll(dir)
 
+	sd := &systemd{dir}
+
 	dst := u.Destination(dir)
 	expectDst := path.Join(dir, "run", "systemd", "network", "50-eth0.network")
 	if dst != expectDst {
 		t.Fatalf("unit.Destination returned %s, expected %s", dst, expectDst)
 	}
 
-	if err := PlaceUnit(&u, dst); err != nil {
+	if err := sd.PlaceUnit(&u, dst); err != nil {
 		t.Fatalf("PlaceUnit failed: %v", err)
 	}
 
@@ -100,13 +102,15 @@ Where=/media/state
 	}
 	defer os.RemoveAll(dir)
 
+	sd := &systemd{dir}
+
 	dst := u.Destination(dir)
 	expectDst := path.Join(dir, "etc", "systemd", "system", "media-state.mount")
 	if dst != expectDst {
 		t.Fatalf("unit.Destination returned %s, expected %s", dst, expectDst)
 	}
 
-	if err := PlaceUnit(&u, dst); err != nil {
+	if err := sd.PlaceUnit(&u, dst); err != nil {
 		t.Fatalf("PlaceUnit failed: %v", err)
 	}
 
@@ -155,9 +159,11 @@ func TestMaskUnit(t *testing.T) {
 	}
 	defer os.RemoveAll(dir)
 
+	sd := &systemd{dir}
+
 	// Ensure mask works with units that do not currently exist
 	uf := &Unit{Name: "foo.service"}
-	if err := MaskUnit(uf, dir); err != nil {
+	if err := sd.MaskUnit(uf); err != nil {
 		t.Fatalf("Unable to mask new unit: %v", err)
 	}
 	fooPath := path.Join(dir, "etc", "systemd", "system", "foo.service")
@@ -175,7 +181,7 @@ func TestMaskUnit(t *testing.T) {
 	if _, err := os.Create(barPath); err != nil {
 		t.Fatalf("Error creating new unit file: %v", err)
 	}
-	if err := MaskUnit(ub, dir); err != nil {
+	if err := sd.MaskUnit(ub); err != nil {
 		t.Fatalf("Unable to mask existing unit: %v", err)
 	}
 	barTgt, err := os.Readlink(barPath)
@@ -194,8 +200,10 @@ func TestUnmaskUnit(t *testing.T) {
 	}
 	defer os.RemoveAll(dir)
 
+	sd := &systemd{dir}
+
 	nilUnit := &Unit{Name: "null.service"}
-	if err := UnmaskUnit(nilUnit, dir); err != nil {
+	if err := sd.UnmaskUnit(nilUnit); err != nil {
 		t.Errorf("unexpected error from unmasking nonexistent unit: %v", err)
 	}
 
@@ -211,7 +219,7 @@ func TestUnmaskUnit(t *testing.T) {
 	if err := ioutil.WriteFile(dst, []byte(uf.Content), 700); err != nil {
 		t.Fatalf("Unable to write unit file: %v", err)
 	}
-	if err := UnmaskUnit(uf, dir); err != nil {
+	if err := sd.UnmaskUnit(uf); err != nil {
 		t.Errorf("unmask of non-empty unit returned unexpected error: %v", err)
 	}
 	got, _ := ioutil.ReadFile(dst)
@@ -224,7 +232,7 @@ func TestUnmaskUnit(t *testing.T) {
 	if err := os.Symlink("/dev/null", dst); err != nil {
 		t.Fatalf("Unable to create masked unit: %v", err)
 	}
-	if err := UnmaskUnit(ub, dir); err != nil {
+	if err := sd.UnmaskUnit(ub); err != nil {
 		t.Errorf("unmask of unit returned unexpected error: %v", err)
 	}
 	if _, err := os.Stat(dst); !os.IsNotExist(err) {

system/unit.go

@@ -0,0 +1,67 @@
+package system
+
+import (
+	"fmt"
+	"path"
+	"path/filepath"
+	"strings"
+)
+
+// Name for drop-in service configuration files created by cloudconfig
+const cloudConfigDropIn = "20-cloudinit.conf"
+
+type UnitManager interface {
+	PlaceUnit(unit *Unit, dst string) error
+	EnableUnitFile(unit string, runtime bool) error
+	RunUnitCommand(command, unit string) (string, error)
+	DaemonReload() error
+	MaskUnit(unit *Unit) error
+	UnmaskUnit(unit *Unit) error
+}
+
+type Unit struct {
+	Name    string
+	Mask    bool
+	Enable  bool
+	Runtime bool
+	Content string
+	Command string
+
+	// For drop-in units, a cloudinit.conf is generated.
+	// This is currently unbound in YAML (and hence unsettable in cloud-config files)
+	// until the correct behaviour for multiple drop-in units is determined.
+	DropIn bool `yaml:"-"`
+}
+
+func (u *Unit) Type() string {
+	ext := filepath.Ext(u.Name)
+	return strings.TrimLeft(ext, ".")
+}
+
+func (u *Unit) Group() (group string) {
+	t := u.Type()
+	if t == "network" || t == "netdev" || t == "link" {
+		group = "network"
+	} else {
+		group = "system"
+	}
+	return
+}
+
+type Script []byte
+
+// Destination builds the appropriate absolute file path for
+// the Unit. The root argument indicates the effective base
+// directory of the system (similar to a chroot).
+func (u *Unit) Destination(root string) string {
+	dir := "etc"
+	if u.Runtime {
+		dir = "run"
+	}
+
+	if u.DropIn {
+		return path.Join(root, dir, "systemd", u.Group(), fmt.Sprintf("%s.d", u.Name), cloudConfigDropIn)
+	} else {
+		return path.Join(root, dir, "systemd", u.Group(), u.Name)
+	}
+}

test

@@ -18,7 +18,7 @@ declare -a TESTPKGS=(initialize system datasource pkg network)
 if [ -z "$PKG" ]; then
 	GOFMTPATH="$TESTPKGS coreos-cloudinit.go"
 	# prepend repo path to each package
-	TESTPKGS=${TESTPKGS[@]/#/${REPO_PATH}/}
+	TESTPKGS="${TESTPKGS[@]/#/${REPO_PATH}/} ./"
 else
 	GOFMTPATH="$TESTPKGS"
 	# strip out slashes and dots from PKG=./foo/

units/user-configdrive.service

@@ -1,7 +1,7 @@
 [Unit]
 Description=Load cloud-config from /media/configdrive
 Requires=coreos-setup-environment.service
-After=coreos-setup-environment.service
+After=coreos-setup-environment.service system-config.target
 Before=user-config.target
 
 # HACK: work around ordering between config drive and ec2 metadata It is
@@ -13,7 +13,6 @@ Before=user-config.target
 # systemd knows about the ordering as early as possible.
 # coreos-cloudinit could implement a simple lock but that cannot be used
 # until after the systemd dbus calls are made non-blocking.
-After=system-cloudinit@usr-share-oem-cloud\x2dconfig.yml.service
 After=ec2-cloudinit.service
 
 [Service]