add kubeadm completion command

cmd/kubeadm/app/cmd/BUILD

@@ -12,6 +12,7 @@ go_library(
     name = "go_default_library",
     srcs = [
         "cmd.go",
+        "completion.go",
         "defaults.go",
         "init.go",
         "join.go",
@@ -41,6 +42,7 @@ go_library(
         "//pkg/bootstrap/api:go_default_library",
         "//pkg/kubectl/cmd/util:go_default_library",
         "//pkg/printers:go_default_library",
+        "//pkg/util/i18n:go_default_library",
         "//pkg/util/initsystem:go_default_library",
         "//pkg/version:go_default_library",
         "//vendor:github.com/blang/semver",

cmd/kubeadm/app/cmd/cmd.go

@@ -78,6 +78,7 @@ func NewKubeadmCommand(f cmdutil.Factory, in io.Reader, out, err io.Writer) *cob
 	cmds.ResetFlags()
 	cmds.SetGlobalNormalizationFunc(flag.WarnWordSepNormalizeFunc)
 
+	cmds.AddCommand(NewCmdCompletion(out, ""))
 	cmds.AddCommand(NewCmdInit(out))
 	cmds.AddCommand(NewCmdJoin(out))
 	cmds.AddCommand(NewCmdReset(out))

cmd/kubeadm/app/cmd/completion.go

@@ -0,0 +1,301 @@
+/*
+Copyright 2017 The Kubernetes Authors.
+
+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 (
+	"bytes"
+	"fmt"
+	"io"
+
+	"github.com/renstrom/dedent"
+	"github.com/spf13/cobra"
+
+	kubeadmutil "k8s.io/kubernetes/cmd/kubeadm/app/util"
+	"k8s.io/kubernetes/pkg/util/i18n"
+)
+
+const defaultBoilerPlate = `
+# Copyright 2017 The Kubernetes Authors.
+#
+# 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.
+`
+
+var (
+	completion_long = dedent.Dedent(`
+		Output shell completion code for the specified shell (bash or zsh).
+		The shell code must be evalutated to provide interactive
+		completion of kubeadm commands.  This can be done by sourcing it from
+		the .bash_profile.
+
+		Note: this requires the bash-completion framework, which is not installed
+		by default on Mac.  This can be installed by using homebrew:
+
+		    $ brew install bash-completion
+
+		Once installed, bash_completion must be evaluated.  This can be done by adding the
+		following line to the .bash_profile
+
+		    $ source $(brew --prefix)/etc/bash_completion
+
+		Note for zsh users: [1] zsh completions are only supported in versions of zsh >= 5.2`)
+
+	completion_example = dedent.Dedent(`
+		# Install bash completion on a Mac using homebrew
+		brew install bash-completion
+		printf "\n# Bash completion support\nsource $(brew --prefix)/etc/bash_completion\n" >> $HOME/.bash_profile
+		source $HOME/.bash_profile
+
+		# Load the kubeadm completion code for bash into the current shell
+		source <(kubeadm completion bash)
+
+		# Write bash completion code to a file and source if from .bash_profile
+		kubeadm completion bash > ~/.kube/kubeadm_completion.bash.inc
+		printf "\n# Kubeadm shell completion\nsource '$HOME/.kube/kubeadm_completion.bash.inc'\n" >> $HOME/.bash_profile
+		source $HOME/.bash_profile
+
+		# Load the kubeadm completion code for zsh[1] into the current shell
+		source <(kubeadm completion zsh)`)
+)
+
+var (
+	completion_shells = map[string]func(out io.Writer, cmd *cobra.Command) error{
+		"bash": runCompletionBash,
+		"zsh":  runCompletionZsh,
+	}
+)
+
+func NewCmdCompletion(out io.Writer, boilerPlate string) *cobra.Command {
+	shells := []string{}
+	for s := range completion_shells {
+		shells = append(shells, s)
+	}
+
+	cmd := &cobra.Command{
+		Use:     "completion SHELL",
+		Short:   i18n.T("Output shell completion code for the specified shell (bash or zsh)"),
+		Long:    completion_long,
+		Example: completion_example,
+		Run: func(cmd *cobra.Command, args []string) {
+			err := RunCompletion(out, boilerPlate, cmd, args)
+			kubeadmutil.CheckErr(err)
+		},
+		ValidArgs: shells,
+	}
+
+	return cmd
+}
+
+func RunCompletion(out io.Writer, boilerPlate string, cmd *cobra.Command, args []string) error {
+	if len(args) == 0 {
+		return fmt.Errorf("shell not specified.")
+	}
+	if len(args) > 1 {
+		return fmt.Errorf("too many arguments. expected only the shell type.")
+	}
+	run, found := completion_shells[args[0]]
+	if !found {
+		return fmt.Errorf("unsupported shell type %q.", args[0])
+	}
+
+	if len(boilerPlate) == 0 {
+		boilerPlate = defaultBoilerPlate
+	}
+	if _, err := out.Write([]byte(boilerPlate)); err != nil {
+		return err
+	}
+	return run(out, cmd.Parent())
+}
+
+func runCompletionBash(out io.Writer, kubeadm *cobra.Command) error {
+	return kubeadm.GenBashCompletion(out)
+}
+
+func runCompletionZsh(out io.Writer, kubeadm *cobra.Command) error {
+	zsh_initialization := `
+__kubeadm_bash_source() {
+	alias shopt=':'
+	alias _expand=_bash_expand
+	alias _complete=_bash_comp
+	emulate -L sh
+	setopt kshglob noshglob braceexpand
+
+	source "$@"
+}
+
+__kubeadm_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 [ "$1" = "__kubeadm_compopt" ]; then
+			echo builtin
+			return 0
+		fi
+	fi
+	type "$@"
+}
+
+__kubeadm_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
+}
+
+__kubeadm_compopt() {
+	true # don't do anything. Not supported by bashcompinit in zsh
+}
+
+__kubeadm_declare() {
+	if [ "$1" == "-F" ]; then
+		whence -w "$@"
+	else
+		builtin declare "$@"
+	fi
+}
+
+__kubeadm_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]#"$colon_word"}
+		done
+	fi
+}
+
+__kubeadm_get_comp_words_by_ref() {
+	cur="${COMP_WORDS[COMP_CWORD]}"
+	prev="${COMP_WORDS[${COMP_CWORD}-1]}"
+	words=("${COMP_WORDS[@]}")
+	cword=("${COMP_CWORD[@]}")
+}
+
+__kubeadm_filedir() {
+	local RET OLD_IFS w qw
+
+	__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="," __debug "RET=${RET[@]} len=${#RET[@]}"
+
+	for w in ${RET[@]}; do
+		if [[ ! "${w}" = "${cur}"* ]]; then
+			continue
+		fi
+		if eval "[[ \"\${w}\" = *.$1 || -d \"\${w}\" ]]"; then
+			qw="$(__kubeadm_quote "${w}")"
+			if [ -d "${w}" ]; then
+				COMPREPLY+=("${qw}/")
+			else
+				COMPREPLY+=("${qw}")
+			fi
+		fi
+	done
+}
+
+__kubeadm_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
+
+__kubeadm_convert_bash_to_zsh() {
+	sed \
+	-e 's/declare -F/whence -w/' \
+	-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}/__kubeadm_filedir/g" \
+	-e "s/${LWORD}_get_comp_words_by_ref${RWORD}/__kubeadm_get_comp_words_by_ref/g" \
+	-e "s/${LWORD}__ltrim_colon_completions${RWORD}/__kubeadm_ltrim_colon_completions/g" \
+	-e "s/${LWORD}compgen${RWORD}/__kubeadm_compgen/g" \
+	-e "s/${LWORD}compopt${RWORD}/__kubeadm_compopt/g" \
+	-e "s/${LWORD}declare${RWORD}/__kubeadm_declare/g" \
+	-e "s/\\\$(type${RWORD}/\$(__kubeadm_type/g" \
+	<<'BASH_COMPLETION_EOF'
+`
+	out.Write([]byte(zsh_initialization))
+
+	buf := new(bytes.Buffer)
+	kubeadm.GenBashCompletion(buf)
+	out.Write(buf.Bytes())
+
+	zsh_tail := `
+BASH_COMPLETION_EOF
+}
+
+__kubeadm_bash_source <(__kubeadm_convert_bash_to_zsh)
+`
+	out.Write([]byte(zsh_tail))
+	return nil
+}