Kubernetes Registry (#1064)

* add teh k8s registry

* add k8s reg config/cmd

* go mod update

util/kubernetes/api/request.go

@@ -2,6 +2,7 @@ package api
 
 import (
 	"bytes"
+	"context"
 	"encoding/json"
 	"errors"
 	"fmt"
@@ -12,6 +13,8 @@ import (
 
 // Request is used to construct a http request for the k8s API.
 type Request struct {
+	// the request context
+	context   context.Context
 	client    *http.Client
 	header    http.Header
 	params    url.Values
@@ -41,6 +44,10 @@ func (r *Request) verb(method string) *Request {
 	return r
 }
 
+func (r *Request) Context(ctx context.Context) {
+	r.context = ctx
+}
+
 // Get request
 func (r *Request) Get() *Request {
 	return r.verb("GET")
@@ -172,8 +179,15 @@ func (r *Request) request() (*http.Request, error) {
 		url += "?" + r.params.Encode()
 	}
 
+	var req *http.Request
+	var err error
+
 	// build request
-	req, err := http.NewRequest(r.method, url, r.body)
+	if r.context != nil {
+		req, err = http.NewRequestWithContext(r.context, r.method, url, r.body)
+	} else {
+		req, err = http.NewRequest(r.method, url, r.body)
+	}
 	if err != nil {
 		return nil, err
 	}

util/kubernetes/api/response.go

@@ -58,6 +58,10 @@ func (r *Response) Into(data interface{}) error {
 	return r.err
 }
 
+func (r *Response) Close() error {
+	return r.res.Body.Close()
+}
+
 func newResponse(res *http.Response, err error) *Response {
 	r := &Response{
 		res: res,

util/kubernetes/client/client.go

@@ -10,7 +10,6 @@ import (
 	"net/http"
 	"os"
 	"path"
-	"strconv"
 	"strings"
 
 	"github.com/micro/go-micro/util/kubernetes/api"
@@ -45,6 +44,8 @@ type Client interface {
 	List(*Resource) error
 	// Log gets log for a pod
 	Log(*Resource, ...LogOption) (io.ReadCloser, error)
+	// Watch for events
+	Watch(*Resource, ...WatchOption) (Watcher, error)
 }
 
 func detectNamespace() (string, error) {
@@ -132,6 +133,8 @@ func (c *client) Update(r *Resource) error {
 		req.Body(r.Value.(*Service))
 	case "deployment":
 		req.Body(r.Value.(*Deployment))
+	case "pod":
+		req.Body(r.Value.(*Pod))
 	default:
 		return errors.New("unsupported resource")
 	}
@@ -157,6 +160,34 @@ func (c *client) List(r *Resource) error {
 	return c.Get(r, labels)
 }
 
+// Watch returns an event stream
+func (c *client) Watch(r *Resource, opts ...WatchOption) (Watcher, error) {
+	var options WatchOptions
+	for _, o := range opts {
+		o(&options)
+	}
+
+	// set the watch param
+	params := &api.Params{Additional: map[string]string{
+		"watch": "true",
+	}}
+
+	// get options params
+	if options.Params != nil {
+		for k, v := range options.Params {
+			params.Additional[k] = v
+		}
+	}
+
+	req := api.NewRequest(c.opts).
+		Get().
+		Resource(r.Kind).
+		Name(r.Name).
+		Params(params)
+
+	return newWatcher(req)
+}
+
 // NewService returns default micro kubernetes service definition
 func NewService(name, version, typ string) *Service {
 	log.Tracef("kubernetes default service: name: %s, version: %s", name, version)
@@ -252,28 +283,22 @@ func NewDeployment(name, version, typ string) *Deployment {
 	}
 }
 
-// NewLocalDevClient returns a client that can be used with `kubectl proxy` on an optional port
-func NewLocalDevClient(port ...int) *client {
-	var p int
-	if len(port) > 1 {
-		log.Fatal("Expected 0 or 1 port parameters")
-	}
-	if len(port) == 0 {
-		p = 8001
-	} else {
-		p = port[0]
+// NewLocalClient returns a client that can be used with `kubectl proxy`
+func NewLocalClient(hosts ...string) *client {
+	if len(hosts) == 0 {
+		hosts[0] = "http://localhost:8001"
 	}
 	return &client{
 		opts: &api.Options{
 			Client:    http.DefaultClient,
-			Host:      "http://localhost:" + strconv.Itoa(p),
+			Host:      hosts[0],
 			Namespace: "default",
 		},
 	}
 }
 
-// NewClientInCluster creates a Kubernetes client for use from within a k8s pod.
-func NewClientInCluster() *client {
+// NewClusterClient creates a Kubernetes client for use from within a k8s pod.
+func NewClusterClient() *client {
 	host := "https://" + os.Getenv("KUBERNETES_SERVICE_HOST") + ":" + os.Getenv("KUBERNETES_SERVICE_PORT")
 
 	s, err := os.Stat(serviceAccountPath)

util/kubernetes/client/options.go

@@ -4,7 +4,12 @@ type LogOptions struct {
 	Params map[string]string
 }
 
+type WatchOptions struct {
+	Params map[string]string
+}
+
 type LogOption func(*LogOptions)
+type WatchOption func(*WatchOptions)
 
 // LogParams provides additional params for logs
 func LogParams(p map[string]string) LogOption {
@@ -12,3 +17,10 @@ func LogParams(p map[string]string) LogOption {
 		l.Params = p
 	}
 }
+
+// WatchParams used for watch params
+func WatchParams(p map[string]string) WatchOption {
+	return func(w *WatchOptions) {
+		w.Params = p
+	}
+}

util/kubernetes/client/types.go

@@ -1,61 +1,5 @@
 package client
 
-// Resource is API resource
-type Resource struct {
-	Name  string
-	Kind  string
-	Value interface{}
-}
-
-// Metadata defines api object metadata
-type Metadata struct {
-	Name        string            `json:"name,omitempty"`
-	Namespace   string            `json:"namespace,omitempty"`
-	Version     string            `json:"version,omitempty"`
-	Labels      map[string]string `json:"labels,omitempty"`
-	Annotations map[string]string `json:"annotations,omitempty"`
-}
-
-// ServicePort configures service ports
-type ServicePort struct {
-	Name     string `json:"name,omitempty"`
-	Port     int    `json:"port"`
-	Protocol string `json:"protocol,omitempty"`
-}
-
-// ServiceSpec provides service configuration
-type ServiceSpec struct {
-	Type     string            `json:"type,omitempty"`
-	Selector map[string]string `json:"selector,omitempty"`
-	Ports    []ServicePort     `json:"ports,omitempty"`
-}
-
-type LoadBalancerIngress struct {
-	IP       string `json:"ip,omitempty"`
-	Hostname string `json:"hostname,omitempty"`
-}
-
-type LoadBalancerStatus struct {
-	Ingress []LoadBalancerIngress `json:"ingress,omitempty"`
-}
-
-// ServiceStatus
-type ServiceStatus struct {
-	LoadBalancer LoadBalancerStatus `json:"loadBalancer,omitempty"`
-}
-
-// Service is kubernetes service
-type Service struct {
-	Metadata *Metadata      `json:"metadata"`
-	Spec     *ServiceSpec   `json:"spec,omitempty"`
-	Status   *ServiceStatus `json:"status,omitempty"`
-}
-
-// ServiceList
-type ServiceList struct {
-	Items []Service `json:"items"`
-}
-
 // ContainerPort
 type ContainerPort struct {
 	Name          string `json:"name,omitempty"`
@@ -79,23 +23,6 @@ type Container struct {
 	Ports   []ContainerPort `json:"ports,omitempty"`
 }
 
-// PodSpec is a pod
-type PodSpec struct {
-	Containers []Container `json:"containers"`
-}
-
-// Template is micro deployment template
-type Template struct {
-	Metadata *Metadata `json:"metadata,omitempty"`
-	PodSpec  *PodSpec  `json:"spec,omitempty"`
-}
-
-// LabelSelector is a label query over a set of resources
-// NOTE: we do not support MatchExpressions at the moment
-type LabelSelector struct {
-	MatchLabels map[string]string `json:"matchLabels,omitempty"`
-}
-
 // DeploymentSpec defines micro deployment spec
 type DeploymentSpec struct {
 	Replicas int            `json:"replicas,omitempty"`
@@ -132,6 +59,93 @@ type DeploymentList struct {
 	Items []Deployment `json:"items"`
 }
 
-type PodList struct {
-	Items []Template `json:"items"`
+// LabelSelector is a label query over a set of resources
+// NOTE: we do not support MatchExpressions at the moment
+type LabelSelector struct {
+	MatchLabels map[string]string `json:"matchLabels,omitempty"`
+}
+
+type LoadBalancerIngress struct {
+	IP       string `json:"ip,omitempty"`
+	Hostname string `json:"hostname,omitempty"`
+}
+
+type LoadBalancerStatus struct {
+	Ingress []LoadBalancerIngress `json:"ingress,omitempty"`
+}
+
+// Metadata defines api object metadata
+type Metadata struct {
+	Name        string            `json:"name,omitempty"`
+	Namespace   string            `json:"namespace,omitempty"`
+	Version     string            `json:"version,omitempty"`
+	Labels      map[string]string `json:"labels,omitempty"`
+	Annotations map[string]string `json:"annotations,omitempty"`
+}
+
+// PodSpec is a pod
+type PodSpec struct {
+	Containers []Container `json:"containers"`
+}
+
+// PodList
+type PodList struct {
+	Items []Pod `json:"items"`
+}
+
+// Pod is the top level item for a pod
+type Pod struct {
+	Metadata *Metadata  `json:"metadata"`
+	Spec     *PodSpec   `json:"spec,omitempty"`
+	Status   *PodStatus `json:"status"`
+}
+
+// PodStatus
+type PodStatus struct {
+	PodIP string `json:"podIP"`
+	Phase string `json:"phase"`
+}
+
+// Resource is API resource
+type Resource struct {
+	Name  string
+	Kind  string
+	Value interface{}
+}
+
+// ServicePort configures service ports
+type ServicePort struct {
+	Name     string `json:"name,omitempty"`
+	Port     int    `json:"port"`
+	Protocol string `json:"protocol,omitempty"`
+}
+
+// ServiceSpec provides service configuration
+type ServiceSpec struct {
+	Type     string            `json:"type,omitempty"`
+	Selector map[string]string `json:"selector,omitempty"`
+	Ports    []ServicePort     `json:"ports,omitempty"`
+}
+
+// ServiceStatus
+type ServiceStatus struct {
+	LoadBalancer LoadBalancerStatus `json:"loadBalancer,omitempty"`
+}
+
+// Service is kubernetes service
+type Service struct {
+	Metadata *Metadata      `json:"metadata"`
+	Spec     *ServiceSpec   `json:"spec,omitempty"`
+	Status   *ServiceStatus `json:"status,omitempty"`
+}
+
+// ServiceList
+type ServiceList struct {
+	Items []Service `json:"items"`
+}
+
+// Template is micro deployment template
+type Template struct {
+	Metadata *Metadata `json:"metadata,omitempty"`
+	PodSpec  *PodSpec  `json:"spec,omitempty"`
 }

util/kubernetes/client/watch.go

@@ -0,0 +1,122 @@
+package client
+
+import (
+	"bufio"
+	"context"
+	"encoding/json"
+	"errors"
+	"net/http"
+
+	"github.com/micro/go-micro/util/kubernetes/api"
+)
+
+const (
+	// EventTypes used
+	Added    EventType = "ADDED"
+	Modified EventType = "MODIFIED"
+	Deleted  EventType = "DELETED"
+	Error    EventType = "ERROR"
+)
+
+// Watcher is used to watch for events
+type Watcher interface {
+	// A channel of events
+	Chan() <-chan Event
+	// Stop the watcher
+	Stop()
+}
+
+// EventType defines the possible types of events.
+type EventType string
+
+// Event represents a single event to a watched resource.
+type Event struct {
+	Type   EventType       `json:"type"`
+	Object json.RawMessage `json:"object"`
+}
+
+// bodyWatcher scans the body of a request for chunks
+type bodyWatcher struct {
+	results chan Event
+	cancel  func()
+	stop    chan bool
+	res     *http.Response
+	req     *api.Request
+}
+
+// Changes returns the results channel
+func (wr *bodyWatcher) Chan() <-chan Event {
+	return wr.results
+}
+
+// Stop cancels the request
+func (wr *bodyWatcher) Stop() {
+	select {
+	case <-wr.stop:
+		return
+	default:
+		// cancel the request
+		wr.cancel()
+		// stop the watcher
+		close(wr.stop)
+	}
+}
+
+func (wr *bodyWatcher) stream() {
+	reader := bufio.NewReader(wr.res.Body)
+
+	go func() {
+		for {
+			// read a line
+			b, err := reader.ReadBytes('\n')
+			if err != nil {
+				return
+			}
+
+			// send the event
+			var event Event
+			if err := json.Unmarshal(b, &event); err != nil {
+				continue
+			}
+
+			select {
+			case <-wr.stop:
+				return
+			case wr.results <- event:
+			}
+		}
+	}()
+}
+
+// newWatcher creates a k8s body watcher for
+// a given http request
+func newWatcher(req *api.Request) (Watcher, error) {
+	// set request context so we can cancel the request
+	ctx, cancel := context.WithCancel(context.Background())
+	req.Context(ctx)
+
+	// do the raw request
+	res, err := req.Raw()
+	if err != nil {
+		return nil, err
+	}
+
+	if res.StatusCode < 200 || res.StatusCode >= 300 {
+		// close the response body
+		res.Body.Close()
+		// return an error
+		return nil, errors.New(res.Request.URL.String() + ": " + res.Status)
+	}
+
+	wr := &bodyWatcher{
+		results: make(chan Event),
+		stop:    make(chan bool),
+		cancel:  cancel,
+		req:     req,
+		res:     res,
+	}
+
+	go wr.stream()
+
+	return wr, nil
+}