Merge pull request #4237 from brendandburns/pd_fix

Add a label command to kubectl.

docs/kubectl.md

@@ -390,6 +390,7 @@ Additional help topics:
   kubectl run-container Run a particular image on the cluster.
   kubectl stop          Gracefully shutdown a resource
   kubectl expose        Take a replicated application and expose it as Kubernetes Service
+  kubectl label         Update the labels on a resource
 
 Use "kubectl help [command]" for more information about that command.
 ```
@@ -1037,3 +1038,60 @@ Usage:
 
 ```
 
+#### label
+Update the labels on a resource.
+
+If --overwrite is true, then existing labels can be overwritten, otherwise attempting to overwrite a label will result in an error.
+If --resource-version is specified, then updates will use this resource version, otherwise the existing resource-version will be used.
+
+Examples:
+  $ kubectl label pods foo unhealthy=true
+  <update a pod with the label 'unhealthy' and the value 'true'>
+
+  $ kubectl label --overwrite pods foo status=unhealthy
+  <update a pod with the label 'status' and the value 'unhealthy' overwritting an existing value>
+  
+  $ kubectl label pods foo status=unhealthy --resource-version=1
+  <update a pod with the label 'status' and the value 'unhealthy' if the resource is unchanged from version 1>
+  
+  $ kubectl label pods foo bar-
+  <update a pod by removing a label named 'bar' if it exists. Does not require the --overwrite flag.>
+
+Usage:
+```
+  kubectl label [--overwrite] <resource> <name> <key-1>=<val-1> ... <key-n>=<val-n> [--resource-version=<version>] [flags]
+
+ Available Flags:
+      --alsologtostderr=false: log to standard error as well as files
+      --api-version="": The API version to use when talking to the server
+  -a, --auth-path="": Path to the auth info file. If missing, prompt the user. Only used if using https.
+      --certificate-authority="": Path to a cert. file for the certificate authority.
+      --client-certificate="": Path to a client key file for TLS.
+      --client-key="": Path to a client key file for TLS.
+      --cluster="": The name of the kubeconfig cluster to use
+      --context="": The name of the kubeconfig context to use
+  -h, --help=false: help for label
+      --insecure-skip-tls-verify=false: If true, the server's certificate will not be checked for validity. This will make your HTTPS connections insecure.
+      --kubeconfig="": Path to the kubeconfig file to use for CLI requests.
+      --log_backtrace_at=:0: when logging hits line file:N, emit a stack trace
+      --log_dir=: If non-empty, write log files in this directory
+      --log_flush_frequency=5s: Maximum number of seconds between log flushes
+      --logtostderr=true: log to standard error instead of files
+      --match-server-version=false: Require server version to match client version
+      --namespace="": If present, the namespace scope for this CLI request.
+      --no-headers=false: When using the default output, don't print headers
+  -o, --output="": Output format: json|yaml|template|templatefile
+      --output-version="": Output the formatted object with the given version (default api-version)
+      --overwrite=false: If true, allow labels to be overwritten, otherwise reject label updates that overwrite existing labels.
+      --resource-version="": If non-empty, the labels update will only succeed if this is the current resource-version for the object.
+  -s, --server="": The address of the Kubernetes API server
+      --stderrthreshold=2: logs at or above this threshold go to stderr
+  -t, --template="": Template string or path to template file to use when -o=template or -o=templatefile.
+      --token="": Bearer token for authentication to the API server.
+      --user="": The name of the kubeconfig user to use
+      --v=0: log level for V logs
+      --validate=false: If true, use a schema to validate the input before sending it
+      --vmodule=: comma-separated list of pattern=N settings for file-filtered logging
+
+```
+

pkg/kubectl/cmd/cmd.go

@@ -215,6 +215,8 @@ Find more information at https://github.com/GoogleCloudPlatform/kubernetes.`,
 	cmds.AddCommand(f.NewCmdStop(out))
 	cmds.AddCommand(f.NewCmdExposeService(out))
 
+	cmds.AddCommand(f.NewCmdLabel(out))
+
 	return cmds
 }
 

pkg/kubectl/cmd/label.go

@@ -0,0 +1,170 @@
+/*
+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 (
+	"fmt"
+	"io"
+	"strings"
+
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/api/meta"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/kubectl/cmd/util"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/kubectl/resource"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/runtime"
+	"github.com/spf13/cobra"
+)
+
+func (f *Factory) NewCmdLabel(out io.Writer) *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "label [--overwrite] <resource> <name> <key-1>=<val-1> ... <key-n>=<val-n> [--resource-version=<version>]",
+		Short: "Update the labels on a resource",
+		Long: `Update the labels on a resource.
+
+If --overwrite is true, then existing labels can be overwritten, otherwise attempting to overwrite a label will result in an error.
+If --resource-version is specified, then updates will use this resource version, otherwise the existing resource-version will be used.
+
+Examples:
+  $ kubectl label pods foo unhealthy=true
+  <update a pod with the label 'unhealthy' and the value 'true'>
+
+  $ kubectl label --overwrite pods foo status=unhealthy
+  <update a pod with the label 'status' and the value 'unhealthy' overwritting an existing value>
+  
+  $ kubectl label pods foo status=unhealthy --resource-version=1
+  <update a pod with the label 'status' and the value 'unhealthy' if the resource is unchanged from version 1>
+  
+  $ kubectl label pods foo bar-
+  <update a pod by removing a label named 'bar' if it exists. Does not require the --overwrite flag.>`,
+		Run: func(cmd *cobra.Command, args []string) {
+			if len(args) < 2 {
+				usageError(cmd, "<resource> <name> is required")
+			}
+			if len(args) < 3 {
+				usageError(cmd, "at least one label update is required.")
+			}
+			res := args[:2]
+			cmdNamespace, err := f.DefaultNamespace(cmd)
+			checkErr(err)
+
+			mapper, _ := f.Object(cmd)
+			mapping, namespace, name := util.ResourceFromArgs(cmd, res, mapper, cmdNamespace)
+			client, err := f.RESTClient(cmd, mapping)
+			checkErr(err)
+
+			labels, remove, err := parseLabels(args[2:])
+			checkErr(err)
+			overwrite := util.GetFlagBool(cmd, "overwrite")
+			resourceVersion := util.GetFlagString(cmd, "resource-version")
+
+			obj, err := updateObject(client, mapping, namespace, name, func(obj runtime.Object) runtime.Object {
+				outObj, err := labelFunc(obj, overwrite, resourceVersion, labels, remove)
+				checkErr(err)
+				return outObj
+			})
+			checkErr(err)
+
+			printer, err := f.PrinterForMapping(cmd, mapping)
+			checkErr(err)
+
+			printer.PrintObj(obj, out)
+		},
+	}
+	util.AddPrinterFlags(cmd)
+	cmd.Flags().Bool("overwrite", false, "If true, allow labels to be overwritten, otherwise reject label updates that overwrite existing labels.")
+	cmd.Flags().String("resource-version", "", "If non-empty, the labels update will only succeed if this is the current resource-version for the object.")
+	return cmd
+}
+
+func updateObject(client resource.RESTClient, mapping *meta.RESTMapping, namespace, name string, updateFn func(runtime.Object) runtime.Object) (runtime.Object, error) {
+	helper := resource.NewHelper(client, mapping)
+
+	obj, err := helper.Get(namespace, name)
+	if err != nil {
+		return nil, err
+	}
+
+	obj = updateFn(obj)
+
+	data, err := helper.Codec.Encode(obj)
+	if err != nil {
+		return nil, err
+	}
+
+	_, err = helper.Update(namespace, name, true, data)
+	if err != nil {
+		return nil, err
+	}
+	return obj, nil
+}
+
+func validateNoOverwrites(meta *api.ObjectMeta, labels map[string]string) error {
+	for key := range labels {
+		if value, found := meta.Labels[key]; found {
+			return fmt.Errorf("'%s' already has a value (%s), and --overwrite is false", key, value)
+		}
+	}
+	return nil
+}
+
+func parseLabels(spec []string) (map[string]string, []string, error) {
+	labels := map[string]string{}
+	var remove []string
+	for _, labelSpec := range spec {
+		if strings.Index(labelSpec, "=") != -1 {
+			parts := strings.Split(labelSpec, "=")
+			if len(parts) != 2 {
+				return nil, nil, fmt.Errorf("invalid label spec: %v", labelSpec)
+			}
+			labels[parts[0]] = parts[1]
+		} else if strings.HasSuffix(labelSpec, "-") {
+			remove = append(remove, labelSpec[:len(labelSpec)-1])
+		} else {
+			return nil, nil, fmt.Errorf("unknown label spec: %v")
+		}
+	}
+	for _, removeLabel := range remove {
+		if _, found := labels[removeLabel]; found {
+			return nil, nil, fmt.Errorf("can not both modify and remove a label in the same command")
+		}
+	}
+	return labels, remove, nil
+}
+
+func labelFunc(obj runtime.Object, overwrite bool, resourceVersion string, labels map[string]string, remove []string) (runtime.Object, error) {
+	meta, err := api.ObjectMetaFor(obj)
+	if err != nil {
+		return nil, err
+	}
+	if !overwrite {
+		if err := validateNoOverwrites(meta, labels); err != nil {
+			return nil, err
+		}
+	}
+
+	for key, value := range labels {
+		meta.Labels[key] = value
+	}
+	for _, label := range remove {
+		delete(meta.Labels, label)
+	}
+
+	if len(resourceVersion) != 0 {
+		meta.ResourceVersion = resourceVersion
+	}
+	return obj, nil
+}

pkg/kubectl/cmd/label_test.go

@@ -0,0 +1,249 @@
+/*
+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 TestValidateLabels(t *testing.T) {
+	tests := []struct {
+		meta      *api.ObjectMeta
+		labels    map[string]string
+		expectErr bool
+		test      string
+	}{
+		{
+			meta: &api.ObjectMeta{
+				Labels: map[string]string{
+					"a": "b",
+					"c": "d",
+				},
+			},
+			labels: map[string]string{
+				"a": "c",
+				"d": "b",
+			},
+			test:      "one shared",
+			expectErr: true,
+		},
+		{
+			meta: &api.ObjectMeta{
+				Labels: map[string]string{
+					"a": "b",
+					"c": "d",
+				},
+			},
+			labels: map[string]string{
+				"b": "d",
+				"c": "a",
+			},
+			test:      "second shared",
+			expectErr: true,
+		},
+		{
+			meta: &api.ObjectMeta{
+				Labels: map[string]string{
+					"a": "b",
+					"c": "d",
+				},
+			},
+			labels: map[string]string{
+				"b": "a",
+				"d": "c",
+			},
+			test: "no overlap",
+		},
+		{
+			meta: &api.ObjectMeta{},
+			labels: map[string]string{
+				"b": "a",
+				"d": "c",
+			},
+			test: "no labels",
+		},
+	}
+	for _, test := range tests {
+		err := validateNoOverwrites(test.meta, test.labels)
+		if test.expectErr && err == nil {
+			t.Errorf("%s: unexpected non-error", test.test)
+		}
+		if !test.expectErr && err != nil {
+			t.Errorf("%s: unexpected error: %v", test.test, err)
+		}
+	}
+}
+
+func TestParseLabels(t *testing.T) {
+	tests := []struct {
+		labels         []string
+		expected       map[string]string
+		expectedRemove []string
+		expectErr      bool
+	}{
+		{
+			labels:   []string{"a=b", "c=d"},
+			expected: map[string]string{"a": "b", "c": "d"},
+		},
+		{
+			labels:   []string{},
+			expected: map[string]string{},
+		},
+		{
+			labels:         []string{"a=b", "c=d", "e-"},
+			expected:       map[string]string{"a": "b", "c": "d"},
+			expectedRemove: []string{"e"},
+		},
+		{
+			labels:    []string{"ab", "c=d"},
+			expectErr: true,
+		},
+		{
+			labels:    []string{"a=b", "c=d", "a-"},
+			expectErr: true,
+		},
+	}
+	for _, test := range tests {
+		labels, remove, err := parseLabels(test.labels)
+		if test.expectErr && err == nil {
+			t.Errorf("unexpected non-error: %v", test)
+		}
+		if !test.expectErr && err != nil {
+			t.Errorf("unexpected error: %v %v", err, test)
+		}
+		if !reflect.DeepEqual(labels, test.expected) {
+			t.Errorf("expected: %v, got %v", test.expected, labels)
+		}
+		if !reflect.DeepEqual(remove, test.expectedRemove) {
+			t.Errorf("expected: %v, got %v", test.expectedRemove, remove)
+		}
+	}
+}
+
+func TestLabelFunc(t *testing.T) {
+	tests := []struct {
+		obj       runtime.Object
+		overwrite bool
+		version   string
+		labels    map[string]string
+		remove    []string
+		expected  runtime.Object
+		expectErr bool
+	}{
+		{
+			obj: &api.Pod{
+				ObjectMeta: api.ObjectMeta{
+					Labels: map[string]string{"a": "b"},
+				},
+			},
+			labels:    map[string]string{"a": "b"},
+			expectErr: true,
+		},
+		{
+			obj: &api.Pod{
+				ObjectMeta: api.ObjectMeta{
+					Labels: map[string]string{"a": "b"},
+				},
+			},
+			labels:    map[string]string{"a": "c"},
+			overwrite: true,
+			expected: &api.Pod{
+				ObjectMeta: api.ObjectMeta{
+					Labels: map[string]string{"a": "c"},
+				},
+			},
+		},
+		{
+			obj: &api.Pod{
+				ObjectMeta: api.ObjectMeta{
+					Labels: map[string]string{"a": "b"},
+				},
+			},
+			labels: map[string]string{"c": "d"},
+			expected: &api.Pod{
+				ObjectMeta: api.ObjectMeta{
+					Labels: map[string]string{"a": "b", "c": "d"},
+				},
+			},
+		},
+		{
+			obj: &api.Pod{
+				ObjectMeta: api.ObjectMeta{
+					Labels: map[string]string{"a": "b"},
+				},
+			},
+			labels:  map[string]string{"c": "d"},
+			version: "2",
+			expected: &api.Pod{
+				ObjectMeta: api.ObjectMeta{
+					Labels:          map[string]string{"a": "b", "c": "d"},
+					ResourceVersion: "2",
+				},
+			},
+		},
+		{
+			obj: &api.Pod{
+				ObjectMeta: api.ObjectMeta{
+					Labels: map[string]string{"a": "b"},
+				},
+			},
+			labels: map[string]string{},
+			remove: []string{"a"},
+			expected: &api.Pod{
+				ObjectMeta: api.ObjectMeta{
+					Labels: map[string]string{},
+				},
+			},
+		},
+		{
+			obj: &api.Pod{
+				ObjectMeta: api.ObjectMeta{
+					Labels: map[string]string{"a": "b", "c": "d"},
+				},
+			},
+			labels: map[string]string{"e": "f"},
+			remove: []string{"a"},
+			expected: &api.Pod{
+				ObjectMeta: api.ObjectMeta{
+					Labels: map[string]string{
+						"c": "d",
+						"e": "f",
+					},
+				},
+			},
+		},
+	}
+	for _, test := range tests {
+		out, err := labelFunc(test.obj, test.overwrite, test.version, test.labels, test.remove)
+		if test.expectErr {
+			if err == nil {
+				t.Errorf("unexpected non-error: %v", test)
+			}
+			continue
+		}
+		if !test.expectErr && err != nil {
+			t.Errorf("unexpected error: %v %v", err, test)
+		}
+		if !reflect.DeepEqual(out, test.expected) {
+			t.Errorf("expected: %v, got %v", test.expected, out)
+		}
+	}
+}