Add add a utility for merging JSON fragments, and use it in run-container.

docs/kubectl.md

@@ -885,7 +885,7 @@ Examples:
 
 Usage:
 ```
-  kubectl run-container <name> --image=<image> [--replicas=replicas] [--dry-run=<bool>] [flags]
+  kubectl run-container <name> --image=<image> [--replicas=replicas] [--dry-run=<bool>] [--overrides=<inline-json>] [flags]
 
  Available Flags:
       --alsologtostderr=false: log to standard error as well as files
@@ -913,6 +913,7 @@ Usage:
       --ns-path="/home/username/.kubernetes_ns": Path to the namespace info file that holds the namespace context to use for CLI requests.
   -o, --output="": Output format: json|yaml|template|templatefile
       --output-version="": Output the formatted object with the given version (default api-version)
+      --overrides="": An inline JSON override for the generated object.  If this is non-empty, it is parsed used to override the generated object
   -r, --replicas=1: Number of replicas to create for this container. Default 1
   -s, --server="": The address of the Kubernetes API server
       --stderrthreshold=2: logs at or above this threshold go to stderr

pkg/kubectl/cmd/helpers.go

@@ -17,6 +17,7 @@ limitations under the License.
 package cmd
 
 import (
+	"encoding/json"
 	"fmt"
 	"io/ioutil"
 	"net/http"
@@ -26,7 +27,10 @@ import (
 	"strings"
 	"time"
 
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/runtime"
 	"github.com/golang/glog"
+	"github.com/imdario/mergo"
 	"github.com/spf13/cobra"
 )
 
@@ -171,3 +175,37 @@ func ReadConfigDataFromLocation(location string) ([]byte, error) {
 		return data, nil
 	}
 }
+
+func Merge(dst runtime.Object, fragment, kind string) error {
+	// Ok, this is a little hairy, we'd rather not force the user to specify a kind for their JSON
+	// So we pull it into a map, add the Kind field, and then reserialize.
+	// We also pull the apiVersion for proper parsing
+	var intermediate interface{}
+	if err := json.Unmarshal([]byte(fragment), &intermediate); err != nil {
+		return err
+	}
+	dataMap, ok := intermediate.(map[string]interface{})
+	if !ok {
+		return fmt.Errorf("Expected a map, found something else: %s", fragment)
+	}
+	version, found := dataMap["apiVersion"]
+	if !found {
+		return fmt.Errorf("Inline JSON requires an apiVersion field")
+	}
+	versionString, ok := version.(string)
+	if !ok {
+		return fmt.Errorf("apiVersion must be a string")
+	}
+	codec := runtime.CodecFor(api.Scheme, versionString)
+
+	intermediate.(map[string]interface{})["kind"] = kind
+	data, err := json.Marshal(intermediate)
+	if err != nil {
+		return err
+	}
+	src, err := codec.Decode(data)
+	if err != nil {
+		return err
+	}
+	return mergo.Merge(dst, src)
+}

pkg/kubectl/cmd/helpers_test.go

@@ -0,0 +1,108 @@
+/*
+Copyright 2014 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 cmd
+
+import (
+	"reflect"
+	"testing"
+
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/runtime"
+)
+
+func TestMerge(t *testing.T) {
+	tests := []struct {
+		obj       runtime.Object
+		fragment  string
+		expected  runtime.Object
+		expectErr bool
+	}{
+		{
+			obj: &api.Pod{
+				ObjectMeta: api.ObjectMeta{
+					Name: "foo",
+				},
+			},
+			fragment: "{ \"apiVersion\": \"v1beta1\" }",
+			expected: &api.Pod{
+				ObjectMeta: api.ObjectMeta{
+					Name: "foo",
+				},
+			},
+		},
+		{
+			obj: &api.Pod{
+				ObjectMeta: api.ObjectMeta{
+					Name: "foo",
+				},
+			},
+			fragment: "{ \"apiVersion\": \"v1beta1\", \"id\": \"baz\", \"desiredState\": { \"host\": \"bar\" } }",
+			expected: &api.Pod{
+				ObjectMeta: api.ObjectMeta{
+					Name: "baz",
+				},
+				Spec: api.PodSpec{
+					Host: "bar",
+				},
+			},
+		},
+		{
+			obj: &api.Pod{
+				ObjectMeta: api.ObjectMeta{
+					Name: "foo",
+				},
+			},
+			fragment: "{ \"apiVersion\": \"v1beta3\", \"spec\": { \"volumes\": [ {\"name\": \"v1\"}, {\"name\": \"v2\"} ] } }",
+			expected: &api.Pod{
+				ObjectMeta: api.ObjectMeta{
+					Name: "foo",
+				},
+				Spec: api.PodSpec{
+					Volumes: []api.Volume{
+						{
+							Name: "v1",
+						},
+						{
+							Name: "v2",
+						},
+					},
+				},
+			},
+		},
+		{
+			obj:       &api.Pod{},
+			fragment:  "invalid json",
+			expected:  &api.Pod{},
+			expectErr: true,
+		},
+	}
+
+	for _, test := range tests {
+		err := Merge(test.obj, test.fragment, "Pod")
+		if !test.expectErr {
+			if err != nil {
+				t.Errorf("unexpected error: %v", err)
+			} else if !reflect.DeepEqual(test.obj, test.expected) {
+				t.Errorf("\nexpected:\n%v\nsaw:\n%v", test.expected, test.obj)
+			}
+		}
+		if test.expectErr && err == nil {
+			t.Errorf("unexpected non-error")
+		}
+	}
+
+}

pkg/kubectl/cmd/run.go

@@ -27,7 +27,7 @@ import (
 
 func (f *Factory) NewCmdRunContainer(out io.Writer) *cobra.Command {
 	cmd := &cobra.Command{
-		Use:   "run-container <name> --image=<image> [--replicas=replicas] [--dry-run=<bool>]",
+		Use:   "run-container <name> --image=<image> [--replicas=replicas] [--dry-run=<bool>] [--overrides=<inline-json>]",
 		Short: "Run a particular image on the cluster.",
 		Long: `Create and run a particular image, possibly replicated.
 Creates a replication controller to manage the created container(s)
@@ -65,6 +65,11 @@ Examples:
 			controller, err := generator.Generate(params)
 			checkErr(err)
 
+			inline := GetFlagString(cmd, "overrides")
+			if len(inline) > 0 {
+				Merge(controller, inline, "ReplicationController")
+			}
+
 			// TODO: extract this flag to a central location, when such a location exists.
 			if !GetFlagBool(cmd, "dry-run") {
 				controller, err = client.ReplicationControllers(namespace).Create(controller.(*api.ReplicationController))
@@ -79,5 +84,6 @@ Examples:
 	cmd.Flags().IntP("replicas", "r", 1, "Number of replicas to create for this container. Default 1")
 	cmd.Flags().Bool("dry-run", false, "If true, only print the object that would be sent, don't actually do anything")
 	cmd.Flags().StringP("labels", "l", "", "Labels to apply to the pod(s) created by this call to run.")
+	cmd.Flags().String("overrides", "", "An inline JSON override for the generated object.  If this is non-empty, it is parsed used to override the generated object")
 	return cmd
 }