Add a label command.

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
+
+```
+