cloudinit/coreos-cloudinit.go
2014-08-15 10:46:46 -07:00

292 lines
8.8 KiB
Go

package main
import (
"flag"
"fmt"
"os"
"sync"
"time"
"github.com/coreos/coreos-cloudinit/datasource"
"github.com/coreos/coreos-cloudinit/datasource/configdrive"
"github.com/coreos/coreos-cloudinit/datasource/file"
"github.com/coreos/coreos-cloudinit/datasource/metadata/ec2"
"github.com/coreos/coreos-cloudinit/datasource/proc_cmdline"
"github.com/coreos/coreos-cloudinit/datasource/url"
"github.com/coreos/coreos-cloudinit/initialize"
"github.com/coreos/coreos-cloudinit/pkg"
"github.com/coreos/coreos-cloudinit/system"
)
const (
version = "0.9.3"
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
ec2MetadataService string
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, "[DEPRECATED - Use -from-ec2-metadata] Download data from metadata service")
flag.StringVar(&sources.ec2MetadataService, "from-ec2-metadata", "", "Download data from the provided 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>", proc_cmdline.ProcCmdlineLocation, proc_cmdline.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() {
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)
}
if convertNetconf != "" && sources.configDrive == "" {
fmt.Println("-convert-netconf flag requires -from-configdrive")
os.Exit(1)
}
switch convertNetconf {
case "":
case "debian":
default:
fmt.Printf("Invalid option to -convert-netconf: '%s'. Supported options: 'debian'\n", convertNetconf)
os.Exit(1)
}
dss := getDatasources()
if len(dss) == 0 {
fmt.Println("Provide at least one of --from-file, --from-configdrive, --from-ec2-metadata, --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.FetchUserdata()
if err != nil {
fmt.Printf("Failed fetching user-data from datasource: %v\n", err)
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()
}
}
// 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 {
switch t := ud.(type) {
case *initialize.CloudConfig:
ccu = t
case system.Script:
script = &t
}
}
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()
}
}
}
// 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)\n", udcc.Hostname, mdcc.Hostname)
} else {
udcc.Hostname = mdcc.Hostname
}
}
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\n", 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, file.NewDatasource(sources.file))
}
if sources.url != "" {
dss = append(dss, url.NewDatasource(sources.url))
}
if sources.configDrive != "" {
dss = append(dss, configdrive.NewDatasource(sources.configDrive))
}
if sources.metadataService {
dss = append(dss, ec2.NewDatasource(ec2.DefaultAddress))
}
if sources.ec2MetadataService != "" {
dss = append(dss, ec2.NewDatasource(sources.ec2MetadataService))
}
if sources.procCmdLine {
dss = append(dss, proc_cmdline.NewDatasource())
}
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.After(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.After(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
}
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
}