pd-ctl: add auto-completion for pd-ctl

tests/pdctl/completion/completion_test.go

@@ -0,0 +1,43 @@
+// Copyright 2020 PingCAP, Inc.
+//
+// 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,
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package completion_test
+
+import (
+	"testing"
+
+	. "github.com/pingcap/check"
+	"github.com/pingcap/pd/v4/tests/pdctl"
+)
+
+func Test(t *testing.T) {
+	TestingT(t)
+}
+
+var _ = Suite(&completionTestSuite{})
+
+type completionTestSuite struct{}
+
+func (s *completionTestSuite) TestCompletion(c *C) {
+	cmd := pdctl.InitCommand()
+
+	// completion command
+	args := []string{"completion", "bash"}
+	_, _, err := pdctl.ExecuteCommandC(cmd, args...)
+	c.Assert(err, IsNil)
+
+	// completion command
+	args = []string{"completion", "zsh"}
+	_, _, err = pdctl.ExecuteCommandC(cmd, args...)
+	c.Assert(err, IsNil)
+}

tests/pdctl/helper.go

@@ -63,6 +63,7 @@ func InitCommand() *cobra.Command {
 		command.NewLogCommand(),
 		command.NewPluginCommand(),
 		command.NewComponentCommand(),
+		command.NewCompletionCommand(),
 	)
 	return rootCmd
 }

tools/pd-ctl/pdctl/command/completion_command.go

@@ -0,0 +1,279 @@
+// Copyright 2020 PingCAP, Inc.
+//
+// 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,
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package command
+
+import (
+	"bytes"
+	"io"
+	"os"
+
+	"github.com/spf13/cobra"
+)
+
+const (
+	completionLongDesc = `
+Output shell completion code for the specified shell (bash or zsh).
+The shell code must be evaluated to provide interactive
+completion of pd-ctl commands.  This can be done by sourcing it from
+the .bash_profile.
+
+Note for zsh users: [1] zsh completions are only supported in versions of zsh >= 5.2
+`
+
+	completionExample = `
+	# Installing bash completion on macOS using homebrew
+	## If running Bash 3.2 included with macOS
+	    brew install bash-completion
+	## or, if running Bash 4.1+
+	    brew install bash-completion@2
+	## If you've installed via other means, you may need add the completion to your completion directory
+	    pd-ctl completion bash > $(brew --prefix)/etc/bash_completion.d/pd-ctl
+
+
+	# Installing bash completion on Linux
+	## If bash-completion is not installed on Linux, please install the 'bash-completion' package
+	## via your distribution's package manager.
+	## Load the pd-ctl completion code for bash into the current shell
+	    source <(pd-ctl completion bash)
+	## Write bash completion code to a file and source if from .bash_profile
+		pd-ctl completion bash > ~/completion.bash.inc
+		printf "
+		# pd-ctl shell completion
+		source '$HOME/completion.bash.inc'
+		" >> $HOME/.bash_profile
+		source $HOME/.bash_profile
+
+	# Load the pd-ctl completion code for zsh[1] into the current shell
+	    source <(pd-ctl completion zsh)
+	# Set the pd-ctl completion code for zsh[1] to autoload on startup
+	    pd-ctl completion zsh > "${fpath[1]}/_pd-ctl"
+`
+)
+
+var (
+	completionShells = map[string]func(out io.Writer, cmd *cobra.Command) error{
+		"bash": runCompletionBash,
+		"zsh":  runCompletionZsh,
+	}
+)
+
+// NewCompletionCommand return a completion subcommand of root command
+func NewCompletionCommand() *cobra.Command {
+	shells := []string{}
+	for s := range completionShells {
+		shells = append(shells, s)
+	}
+
+	cmd := &cobra.Command{
+		Use:                   "completion SHELL",
+		DisableFlagsInUseLine: true,
+		Short:                 "Output shell completion code for the specified shell (bash)",
+		Long:                  completionLongDesc,
+		Example:               completionExample,
+		Run:                   RunCompletion,
+		ValidArgs:             shells,
+	}
+
+	return cmd
+}
+
+// RunCompletion wrapped the bash and zsh completion scripts
+func RunCompletion(cmd *cobra.Command, args []string) {
+	if len(args) == 0 {
+		cmd.Println("Shell not specified.")
+		cmd.Usage()
+		return
+	}
+	if len(args) > 1 {
+		cmd.Println("Too many arguments. Expected only the shell type.")
+		cmd.Usage()
+		return
+	}
+	run, found := completionShells[args[0]]
+	if !found {
+		cmd.Printf("Unsupported shell type %q.\n", args[0])
+		cmd.Usage()
+		return
+	}
+
+	run(os.Stdout, cmd.Root())
+}
+
+func runCompletionBash(out io.Writer, cmd *cobra.Command) error {
+	return cmd.GenBashCompletion(out)
+}
+
+func runCompletionZsh(out io.Writer, cmd *cobra.Command) error {
+	zshHead := "#compdef pd-ctl\n"
+
+	out.Write([]byte(zshHead))
+
+	zshInitialization := `
+__pd-ctl_bash_source() {
+	alias shopt=':'
+	alias _expand=_bash_expand
+	alias _complete=_bash_comp
+	emulate -L sh
+	setopt kshglob noshglob braceexpand
+
+	source "$@"
+}
+
+__pd-ctl_type() {
+	# -t is not supported by zsh
+	if [ "$1" == "-t" ]; then
+		shift
+
+		# fake Bash 4 to disable "complete -o nospace". Instead
+		# "compopt +-o nospace" is used in the code to toggle trailing
+		# spaces. We don't support that, but leave trailing spaces on
+		# all the time
+		if [ "$1" = "__pd-ctl_compopt" ]; then
+			echo builtin
+			return 0
+		fi
+	fi
+	type "$@"
+}
+
+__pd-ctl_compgen() {
+	local completions w
+	completions=( $(compgen "$@") ) || return $?
+
+	# filter by given word as prefix
+	while [[ "$1" = -* && "$1" != -- ]]; do
+		shift
+		shift
+	done
+	if [[ "$1" == -- ]]; then
+		shift
+	fi
+	for w in "${completions[@]}"; do
+		if [[ "${w}" = "$1"* ]]; then
+			echo "${w}"
+		fi
+	done
+}
+
+__pd-ctl_compopt() {
+	true # don't do anything. Not supported by bashcompinit in zsh
+}
+
+__pd-ctl_ltrim_colon_completions()
+{
+	if [[ "$1" == *:* && "$COMP_WORDBREAKS" == *:* ]]; then
+		# Remove colon-word prefix from COMPREPLY items
+		local colon_word=${1%${1##*:}}
+		local i=${#COMPREPLY[*]}
+		while [[ $((--i)) -ge 0 ]]; do
+			COMPREPLY[$i]=${COMPREPLY[$i]#"$colon_word"}
+		done
+	fi
+}
+
+__pd-ctl_get_comp_words_by_ref() {
+	cur="${COMP_WORDS[COMP_CWORD]}"
+	prev="${COMP_WORDS[${COMP_CWORD}-1]}"
+	words=("${COMP_WORDS[@]}")
+	cword=("${COMP_CWORD[@]}")
+}
+
+__pd-ctl_filedir() {
+	local RET OLD_IFS w qw
+
+	__pd-ctl_debug "_filedir $@ cur=$cur"
+	if [[ "$1" = \~* ]]; then
+		# somehow does not work. Maybe, zsh does not call this at all
+		eval echo "$1"
+		return 0
+	fi
+
+	OLD_IFS="$IFS"
+	IFS=$'\n'
+	if [ "$1" = "-d" ]; then
+		shift
+		RET=( $(compgen -d) )
+	else
+		RET=( $(compgen -f) )
+	fi
+	IFS="$OLD_IFS"
+
+	IFS="," __pd-ctl_debug "RET=${RET[@]} len=${#RET[@]}"
+
+	for w in ${RET[@]}; do
+		if [[ ! "${w}" = "${cur}"* ]]; then
+			continue
+		fi
+		if eval "[[ \"\${w}\" = *.$1 || -d \"\${w}\" ]]"; then
+			qw="$(__pd-ctl_quote "${w}")"
+			if [ -d "${w}" ]; then
+				COMPREPLY+=("${qw}/")
+			else
+				COMPREPLY+=("${qw}")
+			fi
+		fi
+	done
+}
+
+__pd-ctl_quote() {
+    if [[ $1 == \'* || $1 == \"* ]]; then
+        # Leave out first character
+        printf %q "${1:1}"
+    else
+    	printf %q "$1"
+    fi
+}
+
+autoload -U +X bashcompinit && bashcompinit
+
+# use word boundary patterns for BSD or GNU sed
+LWORD='[[:<:]]'
+RWORD='[[:>:]]'
+if sed --help 2>&1 | grep -q GNU; then
+	LWORD='\<'
+	RWORD='\>'
+fi
+
+__pd-ctl_convert_bash_to_zsh() {
+	sed \
+	-e 's/declare -F/whence -w/' \
+	-e 's/_get_comp_words_by_ref "\$@"/_get_comp_words_by_ref "\$*"/' \
+	-e 's/local \([a-zA-Z0-9_]*\)=/local \1; \1=/' \
+	-e 's/flags+=("\(--.*\)=")/flags+=("\1"); two_word_flags+=("\1")/' \
+	-e 's/must_have_one_flag+=("\(--.*\)=")/must_have_one_flag+=("\1")/' \
+	-e "s/${LWORD}_filedir${RWORD}/__pd-ctl_filedir/g" \
+	-e "s/${LWORD}_get_comp_words_by_ref${RWORD}/__pd-ctl_get_comp_words_by_ref/g" \
+	-e "s/${LWORD}__ltrim_colon_completions${RWORD}/__pd-ctl_ltrim_colon_completions/g" \
+	-e "s/${LWORD}compgen${RWORD}/__pd-ctl_compgen/g" \
+	-e "s/${LWORD}compopt${RWORD}/__pd-ctl_compopt/g" \
+	-e "s/${LWORD}declare${RWORD}/builtin declare/g" \
+	-e "s/\\\$(type${RWORD}/\$(__pd-ctl_type/g" \
+	<<'BASH_COMPLETION_EOF'
+`
+	out.Write([]byte(zshInitialization))
+
+	buf := new(bytes.Buffer)
+	cmd.GenBashCompletion(buf)
+	out.Write(buf.Bytes())
+
+	zshTail := `
+BASH_COMPLETION_EOF
+}
+
+__pd-ctl_bash_source <(__pd-ctl_convert_bash_to_zsh)
+_complete pd-ctl 2>/dev/null
+`
+	out.Write([]byte(zshTail))
+	return nil
+}

tools/pd-ctl/pdctl/ctl.go

@@ -86,6 +86,7 @@ func getBasicCmd() *cobra.Command {
 		command.NewLogCommand(),
 		command.NewPluginCommand(),
 		command.NewComponentCommand(),
+		command.NewCompletionCommand(),
 	)
 
 	rootCmd.Flags().ParseErrorsWhitelist.UnknownFlags = true