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diff --git a/vendor/github.com/spf13/cobra/bash_completions.md b/vendor/github.com/spf13/cobra/bash_completions.md deleted file mode 100644 index 4ac61ee1..00000000 --- a/vendor/github.com/spf13/cobra/bash_completions.md +++ /dev/null @@ -1,256 +0,0 @@ -# Generating Bash Completions For Your Own cobra.Command - -If you are using the generator you can create a completion command by running - -```bash -cobra add completion -``` - -Update the help text show how to install the bash_completion Linux show here [Kubectl docs show mac options](https://kubernetes.io/docs/tasks/tools/install-kubectl/#enabling-shell-autocompletion) - -Writing the shell script to stdout allows the most flexible use. - -```go -// completionCmd represents the completion command -var completionCmd = &cobra.Command{ - Use: "completion", - Short: "Generates bash completion scripts", - Long: `To load completion run - -. <(bitbucket completion) - -To configure your bash shell to load completions for each session add to your bashrc - -# ~/.bashrc or ~/.profile -. <(bitbucket completion) -`, - Run: func(cmd *cobra.Command, args []string) { - rootCmd.GenBashCompletion(os.Stdout); - }, -} -``` - -**Note:** The cobra generator may include messages printed to stdout for example if the config file is loaded, this will break the auto complete script - - -## Example from kubectl - -Generating bash completions from a cobra command is incredibly easy. An actual program which does so for the kubernetes kubectl binary is as follows: - -```go -package main - -import ( - "io/ioutil" - "os" - - "k8s.io/kubernetes/pkg/kubectl/cmd" - "k8s.io/kubernetes/pkg/kubectl/cmd/util" -) - -func main() { - kubectl := cmd.NewKubectlCommand(util.NewFactory(nil), os.Stdin, ioutil.Discard, ioutil.Discard) - kubectl.GenBashCompletionFile("out.sh") -} -``` - -`out.sh` will get you completions of subcommands and flags. Copy it to `/etc/bash_completion.d/` as described [here](https://debian-administration.org/article/316/An_introduction_to_bash_completion_part_1) and reset your terminal to use autocompletion. If you make additional annotations to your code, you can get even more intelligent and flexible behavior. - -## Creating your own custom functions - -Some more actual code that works in kubernetes: - -```bash -const ( - bash_completion_func = `__kubectl_parse_get() -{ - local kubectl_output out - if kubectl_output=$(kubectl get --no-headers "$1" 2>/dev/null); then - out=($(echo "${kubectl_output}" | awk '{print $1}')) - COMPREPLY=( $( compgen -W "${out[*]}" -- "$cur" ) ) - fi -} - -__kubectl_get_resource() -{ - if [[ ${#nouns[@]} -eq 0 ]]; then - return 1 - fi - __kubectl_parse_get ${nouns[${#nouns[@]} -1]} - if [[ $? -eq 0 ]]; then - return 0 - fi -} - -__kubectl_custom_func() { - case ${last_command} in - kubectl_get | kubectl_describe | kubectl_delete | kubectl_stop) - __kubectl_get_resource - return - ;; - *) - ;; - esac -} -`) -``` - -And then I set that in my command definition: - -```go -cmds := &cobra.Command{ - Use: "kubectl", - Short: "kubectl controls the Kubernetes cluster manager", - Long: `kubectl controls the Kubernetes cluster manager. - -Find more information at https://github.com/GoogleCloudPlatform/kubernetes.`, - Run: runHelp, - BashCompletionFunction: bash_completion_func, -} -``` - -The `BashCompletionFunction` option is really only valid/useful on the root command. Doing the above will cause `__kubectl_custom_func()` (`__<command-use>_custom_func()`) to be called when the built in processor was unable to find a solution. In the case of kubernetes a valid command might look something like `kubectl get pod [mypod]`. If you type `kubectl get pod [tab][tab]` the `__kubectl_customc_func()` will run because the cobra.Command only understood "kubectl" and "get." `__kubectl_custom_func()` will see that the cobra.Command is "kubectl_get" and will thus call another helper `__kubectl_get_resource()`. `__kubectl_get_resource` will look at the 'nouns' collected. In our example the only noun will be `pod`. So it will call `__kubectl_parse_get pod`. `__kubectl_parse_get` will actually call out to kubernetes and get any pods. It will then set `COMPREPLY` to valid pods! - -## Have the completions code complete your 'nouns' - -In the above example "pod" was assumed to already be typed. But if you want `kubectl get [tab][tab]` to show a list of valid "nouns" you have to set them. Simplified code from `kubectl get` looks like: - -```go -validArgs []string = { "pod", "node", "service", "replicationcontroller" } - -cmd := &cobra.Command{ - Use: "get [(-o|--output=)json|yaml|template|...] (RESOURCE [NAME] | RESOURCE/NAME ...)", - Short: "Display one or many resources", - Long: get_long, - Example: get_example, - Run: func(cmd *cobra.Command, args []string) { - err := RunGet(f, out, cmd, args) - util.CheckErr(err) - }, - ValidArgs: validArgs, -} -``` - -Notice we put the "ValidArgs" on the "get" subcommand. Doing so will give results like - -```bash -# kubectl get [tab][tab] -node pod replicationcontroller service -``` - -## Plural form and shortcuts for nouns - -If your nouns have a number of aliases, you can define them alongside `ValidArgs` using `ArgAliases`: - -```go -argAliases []string = { "pods", "nodes", "services", "svc", "replicationcontrollers", "rc" } - -cmd := &cobra.Command{ - ... - ValidArgs: validArgs, - ArgAliases: argAliases -} -``` - -The aliases are not shown to the user on tab completion, but they are accepted as valid nouns by -the completion algorithm if entered manually, e.g. in: - -```bash -# kubectl get rc [tab][tab] -backend frontend database -``` - -Note that without declaring `rc` as an alias, the completion algorithm would show the list of nouns -in this example again instead of the replication controllers. - -## Mark flags as required - -Most of the time completions will only show subcommands. But if a flag is required to make a subcommand work, you probably want it to show up when the user types [tab][tab]. Marking a flag as 'Required' is incredibly easy. - -```go -cmd.MarkFlagRequired("pod") -cmd.MarkFlagRequired("container") -``` - -and you'll get something like - -```bash -# kubectl exec [tab][tab][tab] --c --container= -p --pod= -``` - -# Specify valid filename extensions for flags that take a filename - -In this example we use --filename= and expect to get a json or yaml file as the argument. To make this easier we annotate the --filename flag with valid filename extensions. - -```go - annotations := []string{"json", "yaml", "yml"} - annotation := make(map[string][]string) - annotation[cobra.BashCompFilenameExt] = annotations - - flag := &pflag.Flag{ - Name: "filename", - Shorthand: "f", - Usage: usage, - Value: value, - DefValue: value.String(), - Annotations: annotation, - } - cmd.Flags().AddFlag(flag) -``` - -Now when you run a command with this filename flag you'll get something like - -```bash -# kubectl create -f -test/ example/ rpmbuild/ -hello.yml test.json -``` - -So while there are many other files in the CWD it only shows me subdirs and those with valid extensions. - -# Specify custom flag completion - -Similar to the filename completion and filtering using cobra.BashCompFilenameExt, you can specify -a custom flag completion function with cobra.BashCompCustom: - -```go - annotation := make(map[string][]string) - annotation[cobra.BashCompCustom] = []string{"__kubectl_get_namespaces"} - - flag := &pflag.Flag{ - Name: "namespace", - Usage: usage, - Annotations: annotation, - } - cmd.Flags().AddFlag(flag) -``` - -In addition add the `__handle_namespace_flag` implementation in the `BashCompletionFunction` -value, e.g.: - -```bash -__kubectl_get_namespaces() -{ - local template - template="{{ range .items }}{{ .metadata.name }} {{ end }}" - local kubectl_out - if kubectl_out=$(kubectl get -o template --template="${template}" namespace 2>/dev/null); then - COMPREPLY=( $( compgen -W "${kubectl_out}[*]" -- "$cur" ) ) - fi -} -``` -# Using bash aliases for commands - -You can also configure the `bash aliases` for the commands and they will also support completions. - -```bash -alias aliasname=origcommand -complete -o default -F __start_origcommand aliasname - -# and now when you run `aliasname` completion will make -# suggestions as it did for `origcommand`. - -$) aliasname <tab><tab> -completion firstcommand secondcommand -``` |