Add backend support for logs

src/app/backend/apihandler.go

@@ -59,6 +59,15 @@ func CreateHttpApiHandler(client *client.Client) http.Handler {
 			Writes(NamespacesList{}))
 	wsContainer.Add(namespaceListWs)
 
+	logsWs := new(restful.WebService)
+	logsWs.Path("/api/logs").
+		Produces(restful.MIME_JSON)
+	logsWs.Route(
+		logsWs.GET("/{namespace}/{podId}").
+			To(apiHandler.handleLogs).
+			Writes(Logs{}))
+	wsContainer.Add(logsWs)
+
 	return wsContainer
 }
 
@@ -122,6 +131,19 @@ func (apiHandler *ApiHandler) handleGetNamespaceList(
 	response.WriteHeaderAndEntity(http.StatusCreated, result)
 }
 
+// Handles log API call.
+func (apiHandler *ApiHandler) handleLogs(request *restful.Request, response *restful.Response) {
+
+	namespace := request.PathParameter("namespace")
+	podId := request.PathParameter("podId")
+	result, err := GetPodLogs(apiHandler.client, namespace, podId)
+	if err != nil {
+		handleInternalError(response, err)
+		return
+	}
+	response.WriteHeaderAndEntity(http.StatusCreated, result)
+}
+
 // Handler that writes the given error to the response and sets appropriate HTTP status headers.
 func handleInternalError(response *restful.Response, err error) {
 	response.AddHeader("Content-Type", "text/plain")

src/app/backend/logs.go

+// Copyright 2015 Google Inc. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package main
+
+import (
+	"io/ioutil"
+	api "k8s.io/kubernetes/pkg/api"
+	client "k8s.io/kubernetes/pkg/client/unversioned"
+	"strings"
+	"time"
+)
+
+// Log response structure
+type Logs struct {
+	// Pod id
+	PodId string `json:"podId"`
+	// Specific date (RFC3339) when logs started
+	SinceTime string `json:"sinceTime"`
+	// Logs string
+	Logs []string `json:"logs"`
+}
+
+// Return logs for particular pod or error when occurred.
+func GetPodLogs(client *client.Client, namespace string, podId string) (*Logs, error) {
+
+	pod, err := client.Pods(namespace).Get(podId)
+	if err != nil {
+		return nil, err
+	}
+
+	logOptions := &api.PodLogOptions{
+		Follow:     false,
+		Previous:   false,
+		Timestamps: true,
+	}
+
+	logString, err := getRawPodLogs(client, namespace, podId, logOptions)
+	if err != nil {
+		return nil, err
+	}
+	logs := &Logs{
+		PodId:     podId,
+		SinceTime: pod.CreationTimestamp.Format(time.RFC3339),
+		Logs:      strings.Split(logString, "\n"),
+	}
+	return logs, nil
+}
+
+// Construct a request for getting the logs for a pod and retrieves the logs.
+func getRawPodLogs(client *client.Client, namespace string, podID string,
+	logOptions *api.PodLogOptions) (string, error) {
+	req := client.RESTClient.Get().
+		Namespace(namespace).
+		Name(podID).
+		Resource("pods").
+		SubResource("log").
+		VersionedParams(logOptions, api.Scheme)
+
+	readCloser, err := req.Stream()
+	if err != nil {
+		return "", err
+	}
+
+	defer readCloser.Close()
+
+	result, err := ioutil.ReadAll(readCloser)
+	if err != nil {
+		return "", err
+	}
+	return string(result), nil
+}