kube-ps1.plugin.zsh
13917 bytes
1#!/usr/bin/env bash
2
3# Kubernetes prompt helper for bash/zsh
4# Displays current context and namespace
5
6# Copyright 2026 Jon Mosco
7#
8# Licensed under the Apache License, Version 2.0 (the "License");
9# you may not use this file except in compliance with the License.
10# You may obtain a copy of the License at
11#
12# http://www.apache.org/licenses/LICENSE-2.0
13#
14# Unless required by applicable law or agreed to in writing, software
15# distributed under the License is distributed on an "AS IS" BASIS,
16# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
17# See the License for the specific language governing permissions and
18# limitations under the License.
19
20# Debug
21[[ -n $DEBUG ]] && set -x
22
23# Default values for the prompt
24# Override these values in ~/.zshrc or ~/.bashrc
25KUBE_PS1_BINARY="${KUBE_PS1_BINARY:-kubectl}"
26KUBE_PS1_SYMBOL_ENABLE="${KUBE_PS1_SYMBOL_ENABLE:-true}"
27KUBE_PS1_SYMBOL_PADDING="${KUBE_PS1_SYMBOL_PADDING:-false}"
28KUBE_PS1_SYMBOL_COLOR="${KUBE_PS1_SYMBOL_COLOR:-}"
29
30KUBE_PS1_NS_ENABLE="${KUBE_PS1_NS_ENABLE:-true}"
31KUBE_PS1_CONTEXT_ENABLE="${KUBE_PS1_CONTEXT_ENABLE:-true}"
32KUBE_PS1_PREFIX="${KUBE_PS1_PREFIX-(}"
33KUBE_PS1_SEPARATOR="${KUBE_PS1_SEPARATOR-|}"
34KUBE_PS1_DIVIDER="${KUBE_PS1_DIVIDER-:}"
35KUBE_PS1_SUFFIX="${KUBE_PS1_SUFFIX-)}"
36
37KUBE_PS1_HIDE_IF_NOCONTEXT="${KUBE_PS1_HIDE_IF_NOCONTEXT:-false}"
38
39_KUBE_PS1_KUBECONFIG_CACHE="${KUBECONFIG}"
40_KUBE_PS1_DISABLE_PATH="${HOME}/.kube/kube-ps1/disabled"
41_KUBE_PS1_LAST_TIME=0
42
43# Determine our shell
44_kube_ps1_shell_type() {
45 local _KUBE_PS1_SHELL_TYPE
46
47 if [ "${ZSH_VERSION-}" ]; then
48 _KUBE_PS1_SHELL_TYPE="zsh"
49 elif [ "${BASH_VERSION-}" ]; then
50 _KUBE_PS1_SHELL_TYPE="bash"
51 fi
52 echo "$_KUBE_PS1_SHELL_TYPE"
53}
54
55_kube_ps1_init() {
56 [[ -f "${_KUBE_PS1_DISABLE_PATH}" ]] && KUBE_PS1_ENABLED=off
57
58 # Detect shell type once and cache it
59 _KUBE_PS1_SHELL="$(_kube_ps1_shell_type)"
60
61 # Check tput availability once
62 if tput setaf 1 &> /dev/null; then
63 _KUBE_PS1_TPUT_AVAILABLE=true
64 else
65 _KUBE_PS1_TPUT_AVAILABLE=false
66 fi
67
68 # Detect stat type once (not needed for zsh which uses zstat builtin)
69 if [[ "${_KUBE_PS1_SHELL}" != "zsh" ]]; then
70 if stat -c "%s" /dev/null &> /dev/null; then
71 _KUBE_PS1_STAT_TYPE="gnu"
72 else
73 _KUBE_PS1_STAT_TYPE="bsd"
74 fi
75 fi
76
77 case "${_KUBE_PS1_SHELL}" in
78 "zsh")
79 _KUBE_PS1_OPEN_ESC="%{"
80 _KUBE_PS1_CLOSE_ESC="%}"
81 _KUBE_PS1_DEFAULT_BG="%k"
82 _KUBE_PS1_DEFAULT_FG="%f"
83 setopt PROMPT_SUBST
84 autoload -U add-zsh-hook
85 add-zsh-hook precmd _kube_ps1_prompt_update
86 zmodload -F zsh/stat b:zstat
87 zmodload zsh/datetime
88 ;;
89 "bash")
90 _KUBE_PS1_OPEN_ESC=$'\001'
91 _KUBE_PS1_CLOSE_ESC=$'\002'
92 _KUBE_PS1_DEFAULT_BG=$'\033[49m'
93 _KUBE_PS1_DEFAULT_FG=$'\033[39m'
94 [[ $PROMPT_COMMAND =~ _kube_ps1_prompt_update ]] || PROMPT_COMMAND="_kube_ps1_prompt_update;${PROMPT_COMMAND:-:}"
95 ;;
96 esac
97}
98
99_kube_ps1_color_fg() {
100 local _KUBE_PS1_FG_CODE
101 case "${1}" in
102 black) _KUBE_PS1_FG_CODE=0;;
103 red) _KUBE_PS1_FG_CODE=1;;
104 green) _KUBE_PS1_FG_CODE=2;;
105 yellow) _KUBE_PS1_FG_CODE=3;;
106 blue) _KUBE_PS1_FG_CODE=4;;
107 magenta) _KUBE_PS1_FG_CODE=5;;
108 cyan) _KUBE_PS1_FG_CODE=6;;
109 white) _KUBE_PS1_FG_CODE=7;;
110 # 256 colors
111 [0-9]|[1-9][0-9]|[1][0-9][0-9]|[2][0-4][0-9]|[2][5][0-5]) _KUBE_PS1_FG_CODE="${1}";;
112 *) _KUBE_PS1_FG_CODE=default
113 esac
114
115 if [[ "${_KUBE_PS1_FG_CODE}" == "default" ]]; then
116 _KUBE_PS1_FG_CODE="${_KUBE_PS1_DEFAULT_FG}"
117 return
118 elif [[ "${_KUBE_PS1_SHELL}" == "zsh" ]]; then
119 _KUBE_PS1_FG_CODE="%F{$_KUBE_PS1_FG_CODE}"
120 elif [[ "${_KUBE_PS1_SHELL}" == "bash" ]]; then
121 if [[ "${_KUBE_PS1_TPUT_AVAILABLE}" == "true" ]]; then
122 _KUBE_PS1_FG_CODE="$(tput setaf "${_KUBE_PS1_FG_CODE}")"
123 elif [[ $_KUBE_PS1_FG_CODE -ge 0 ]] && [[ $_KUBE_PS1_FG_CODE -le 255 ]]; then
124 _KUBE_PS1_FG_CODE="\033[38;5;${_KUBE_PS1_FG_CODE}m"
125 else
126 _KUBE_PS1_FG_CODE="${_KUBE_PS1_DEFAULT_FG}"
127 fi
128 fi
129 echo "${_KUBE_PS1_OPEN_ESC}${_KUBE_PS1_FG_CODE}${_KUBE_PS1_CLOSE_ESC}"
130}
131
132_kube_ps1_color_bg() {
133 local _KUBE_PS1_BG_CODE
134 case "${1}" in
135 black) _KUBE_PS1_BG_CODE=0;;
136 red) _KUBE_PS1_BG_CODE=1;;
137 green) _KUBE_PS1_BG_CODE=2;;
138 yellow) _KUBE_PS1_BG_CODE=3;;
139 blue) _KUBE_PS1_BG_CODE=4;;
140 magenta) _KUBE_PS1_BG_CODE=5;;
141 cyan) _KUBE_PS1_BG_CODE=6;;
142 white) _KUBE_PS1_BG_CODE=7;;
143 # 256 colors
144 [0-9]|[1-9][0-9]|[1][0-9][0-9]|[2][0-4][0-9]|[2][5][0-5]) _KUBE_PS1_BG_CODE="${1}";;
145 *) _KUBE_PS1_BG_CODE=default
146 esac
147
148 if [[ "${_KUBE_PS1_BG_CODE}" == "default" ]]; then
149 _KUBE_PS1_BG_CODE="${_KUBE_PS1_DEFAULT_BG}"
150 return
151 elif [[ "${_KUBE_PS1_SHELL}" == "zsh" ]]; then
152 _KUBE_PS1_BG_CODE="%K{$_KUBE_PS1_BG_CODE}"
153 elif [[ "${_KUBE_PS1_SHELL}" == "bash" ]]; then
154 if [[ "${_KUBE_PS1_TPUT_AVAILABLE}" == "true" ]]; then
155 _KUBE_PS1_BG_CODE="$(tput setab "${_KUBE_PS1_BG_CODE}")"
156 elif [[ $_KUBE_PS1_BG_CODE -ge 0 ]] && [[ $_KUBE_PS1_BG_CODE -le 255 ]]; then
157 _KUBE_PS1_BG_CODE="\033[48;5;${_KUBE_PS1_BG_CODE}m"
158 else
159 _KUBE_PS1_BG_CODE="${_KUBE_PS1_DEFAULT_BG}"
160 fi
161 fi
162 echo "${_KUBE_PS1_OPEN_ESC}${_KUBE_PS1_BG_CODE}${_KUBE_PS1_CLOSE_ESC}"
163}
164
165_kube_ps1_binary_check() {
166 command -v "$1" >/dev/null
167}
168
169_kube_ps1_symbol() {
170 # Exit early if symbol display is disabled
171 [[ "${KUBE_PS1_SYMBOL_ENABLE}" == false ]] && return
172
173 local symbol_arg="${KUBE_PS1_SYMBOL_CUSTOM}"
174
175 local symbol=""
176 local symbol_default=$'\u2388'
177 local symbol_img="☸️"
178 local k8s_glyph=$'\Uf10fe'
179 local k8s_symbol_color=blue
180 local oc_glyph=$'\ue7b7'
181 local oc_symbol_color=red
182 local custom_symbol_color="${KUBE_PS1_SYMBOL_COLOR:-$k8s_symbol_color}"
183 local KUBE_PS1_RESET_COLOR="${_KUBE_PS1_OPEN_ESC}${_KUBE_PS1_DEFAULT_FG}${_KUBE_PS1_CLOSE_ESC}"
184
185 # Choose the symbol based on the provided argument or environment variable
186 case "${symbol_arg}" in
187 "img")
188 symbol="${symbol_img}"
189 ;;
190 "k8s")
191 symbol="$(_kube_ps1_color_fg "${custom_symbol_color}")${k8s_glyph}${KUBE_PS1_RESET_COLOR}"
192 ;;
193 "oc")
194 symbol="$(_kube_ps1_color_fg ${oc_symbol_color})${oc_glyph}${KUBE_PS1_RESET_COLOR}"
195 ;;
196 *)
197 case "${_KUBE_PS1_SHELL}" in
198 bash)
199 if ((BASH_VERSINFO[0] >= 4)) && [[ $'\u2388' != "\\u2388" ]]; then
200 symbol="$(_kube_ps1_color_fg $custom_symbol_color)${symbol_default}${KUBE_PS1_RESET_COLOR}"
201 symbol_img=$'\u2638\ufe0f'
202 else
203 symbol=$'\xE2\x8E\x88'
204 symbol_img=$'\xE2\x98\xB8'
205 fi
206 ;;
207 zsh)
208 symbol="$(_kube_ps1_color_fg $custom_symbol_color)${symbol_default}${KUBE_PS1_RESET_COLOR}"
209 symbol_img="☸️"
210 ;;
211 *)
212 symbol="k8s"
213 esac
214 esac
215
216 # Append padding if enabled
217 if [[ "${KUBE_PS1_SYMBOL_PADDING}" == true ]]; then
218 echo "${symbol} "
219 else
220 echo "${symbol}"
221 fi
222}
223
224_kube_ps1_split_config() {
225 type setopt >/dev/null 2>&1 && setopt SH_WORD_SPLIT
226 local IFS=$1
227 echo $2
228}
229
230_kube_ps1_file_newer_than() {
231 local mtime
232 local file=$1
233 local check_time=$2
234
235 if [[ "${_KUBE_PS1_SHELL}" == "zsh" ]]; then
236 # Use zstat '-F %s.%s' to make it compatible with low zsh version (eg: 5.0.2)
237 mtime=$(zstat -L +mtime -F %s.%s "${file}")
238 elif [[ "${_KUBE_PS1_STAT_TYPE}" == "gnu" ]]; then
239 mtime=$(stat -L -c %Y "${file}")
240 else
241 mtime=$(stat -L -f %m "$file")
242 fi
243
244 [[ "${mtime}" -gt "${check_time}" ]] && return 0
245
246 # If the path is a symlink, also check the symlink's own mtime
247 if [[ -L "${file}" ]]; then
248 if [[ "${_KUBE_PS1_SHELL}" == "zsh" ]]; then
249 mtime=$(zstat +mtime -F %s.%s "${file}")
250 elif [[ "${_KUBE_PS1_STAT_TYPE}" == "gnu" ]]; then
251 mtime=$(stat -c %Y "${file}")
252 else
253 mtime=$(stat -f %m "$file")
254 fi
255 [[ "${mtime}" -gt "${check_time}" ]] && return 0
256 fi
257
258 return 1
259}
260
261_kube_ps1_prompt_update() {
262 local return_code=$?
263
264 [[ "${KUBE_PS1_ENABLED}" == "off" ]] && return $return_code
265
266 if ! _kube_ps1_binary_check "${KUBE_PS1_BINARY}"; then
267 # No ability to fetch context/namespace; display N/A.
268 KUBE_PS1_CONTEXT="BINARY-N/A"
269 KUBE_PS1_NAMESPACE="N/A"
270 return $return_code
271 fi
272
273 if [[ "${KUBECONFIG}" != "${_KUBE_PS1_KUBECONFIG_CACHE}" ]]; then
274 # User changed KUBECONFIG; unconditionally refetch.
275 _KUBE_PS1_KUBECONFIG_CACHE=${KUBECONFIG}
276 _kube_ps1_get_context_ns
277 return $return_code
278 fi
279
280 # kubectl will read the environment variable $KUBECONFIG
281 # otherwise set it to ~/.kube/config
282 local conf
283 local config_file_cache
284
285 for conf in $(_kube_ps1_split_config : "${KUBECONFIG:-${HOME}/.kube/config}"); do
286 [[ -r "${conf}" ]] || continue
287 config_file_cache+=":${conf}"
288 if _kube_ps1_file_newer_than "${conf}" "${_KUBE_PS1_LAST_TIME}"; then
289 _kube_ps1_get_context_ns
290 return $return_code
291 fi
292 done
293
294 if [[ "${config_file_cache}" != "${_KUBE_PS1_CFGFILES_READ_CACHE}" ]]; then
295 _kube_ps1_get_context_ns
296 return $return_code
297 fi
298
299 return $return_code
300}
301
302_kube_ps1_get_context() {
303 if [[ "${KUBE_PS1_CONTEXT_ENABLE}" == true ]]; then
304 KUBE_PS1_CONTEXT="$(${KUBE_PS1_BINARY} config current-context 2>/dev/null)"
305 KUBE_PS1_CONTEXT="${KUBE_PS1_CONTEXT:-N/A}"
306
307 if [[ -n "${KUBE_PS1_CLUSTER_FUNCTION}" ]]; then
308 KUBE_PS1_CONTEXT="$("${KUBE_PS1_CLUSTER_FUNCTION}" "${KUBE_PS1_CONTEXT}")"
309 fi
310 fi
311}
312
313_kube_ps1_get_ns() {
314 if [[ "${KUBE_PS1_NS_ENABLE}" == true ]]; then
315 KUBE_PS1_NAMESPACE="$(${KUBE_PS1_BINARY} config view --minify --output 'jsonpath={..namespace}' 2>/dev/null)"
316 KUBE_PS1_NAMESPACE="${KUBE_PS1_NAMESPACE:-N/A}"
317
318 if [[ -n "${KUBE_PS1_NAMESPACE_FUNCTION}" ]]; then
319 KUBE_PS1_NAMESPACE="$("${KUBE_PS1_NAMESPACE_FUNCTION}" "${KUBE_PS1_NAMESPACE}")"
320 fi
321 fi
322}
323
324_kube_ps1_get_context_ns() {
325 # Set the command time
326 if [[ "${_KUBE_PS1_SHELL}" == "bash" ]]; then
327 if ((BASH_VERSINFO[0] > 4 || (BASH_VERSINFO[0] == 4 && BASH_VERSINFO[1] >= 2))); then
328 _KUBE_PS1_LAST_TIME=$(printf '%(%s)T')
329 else
330 _KUBE_PS1_LAST_TIME=$(date +%s)
331 fi
332 elif [[ "${_KUBE_PS1_SHELL}" == "zsh" ]]; then
333 _KUBE_PS1_LAST_TIME=$EPOCHREALTIME
334 fi
335
336 # Cache which cfgfiles we can read in case they change.
337 local conf
338 _KUBE_PS1_CFGFILES_READ_CACHE=
339 for conf in $(_kube_ps1_split_config : "${KUBECONFIG:-${HOME}/.kube/config}"); do
340 [[ -r $conf ]] && _KUBE_PS1_CFGFILES_READ_CACHE+=":$conf"
341 done
342
343 _kube_ps1_get_context
344 _kube_ps1_get_ns
345}
346
347# Set kube-ps1 shell defaults
348_kube_ps1_init
349
350_kubeon_usage() {
351 cat <<"EOF"
352Toggle kube-ps1 prompt on
353
354Usage: kubeon [-g | --global] [-h | --help]
355
356With no arguments, turn on kube-ps1 status for this shell instance (default).
357
358 -g --global turn on kube-ps1 status globally
359 -h --help print this message
360EOF
361}
362
363_kubeoff_usage() {
364 cat <<"EOF"
365Toggle kube-ps1 prompt off
366
367Usage: kubeoff [-g | --global] [-h | --help]
368
369With no arguments, turn off kube-ps1 status for this shell instance (default).
370
371 -g --global turn off kube-ps1 status globally
372 -h --help print this message
373EOF
374}
375
376kubeon() {
377 if [[ "${1}" == '-h' || "${1}" == '--help' ]]; then
378 _kubeon_usage
379 return 0
380 elif [[ "${1}" == '-g' || "${1}" == '--global' ]]; then
381 rm -f -- "${_KUBE_PS1_DISABLE_PATH}"
382 elif [[ "$#" -ne 0 ]]; then
383 echo -e "error: unrecognized flag ${1}\\n" >&2
384 _kubeon_usage
385 return 1
386 fi
387
388 KUBE_PS1_ENABLED=on
389}
390
391kubeoff() {
392 if [[ "${1}" == '-h' || "${1}" == '--help' ]]; then
393 _kubeoff_usage
394 return 0
395 elif [[ "${1}" == '-g' || "${1}" == '--global' ]]; then
396 mkdir -p -- "$(dirname "${_KUBE_PS1_DISABLE_PATH}")"
397 touch -- "${_KUBE_PS1_DISABLE_PATH}"
398 elif [[ $# -ne 0 ]]; then
399 echo -e "error: unrecognized flag ${1}\\n" >&2
400 _kubeoff_usage
401 return 1
402 fi
403
404 KUBE_PS1_ENABLED=off
405}
406
407# Build our prompt
408kube_ps1() {
409 [[ "${KUBE_PS1_ENABLED}" == "off" ]] && return
410 [[ -z "${KUBE_PS1_CONTEXT}" ]] && [[ "${KUBE_PS1_CONTEXT_ENABLE}" == true ]] && return
411 [[ "${KUBE_PS1_CONTEXT}" == "N/A" ]] && [[ ${KUBE_PS1_HIDE_IF_NOCONTEXT} == true ]] && return
412
413 local KUBE_PS1
414 local KUBE_PS1_RESET_COLOR="${_KUBE_PS1_OPEN_ESC}${_KUBE_PS1_DEFAULT_FG}${_KUBE_PS1_CLOSE_ESC}"
415
416 # Background Color
417 [[ -n "${KUBE_PS1_BG_COLOR}" ]] && KUBE_PS1+="$(_kube_ps1_color_bg "${KUBE_PS1_BG_COLOR}")"
418
419 # Prefix
420 if [[ -z "${KUBE_PS1_PREFIX_COLOR:-}" ]] && [[ -n "${KUBE_PS1_PREFIX}" ]]; then
421 KUBE_PS1+="${KUBE_PS1_PREFIX}"
422 else
423 KUBE_PS1+="$(_kube_ps1_color_fg "${KUBE_PS1_PREFIX_COLOR}")${KUBE_PS1_PREFIX}${KUBE_PS1_RESET_COLOR}"
424 fi
425
426 # Symbol
427 KUBE_PS1+="$(_kube_ps1_symbol)"
428
429 if [[ -n "${KUBE_PS1_SEPARATOR}" ]] && [[ "${KUBE_PS1_SYMBOL_ENABLE}" == true ]]; then
430 KUBE_PS1+="${KUBE_PS1_SEPARATOR}"
431 fi
432
433 # Context
434 if [[ "${KUBE_PS1_CONTEXT_ENABLE}" == true ]]; then
435 local ctx_color="${KUBE_PS1_CTX_COLOR:-red}"
436
437 # Allow custom function to override color based on context
438 if [[ -n "${KUBE_PS1_CTX_COLOR_FUNCTION}" ]]; then
439 ctx_color="$("${KUBE_PS1_CTX_COLOR_FUNCTION}" "${KUBE_PS1_CONTEXT}")"
440 fi
441
442 KUBE_PS1+="$(_kube_ps1_color_fg "${ctx_color}")${KUBE_PS1_CONTEXT}${KUBE_PS1_RESET_COLOR}"
443 fi
444
445 # Namespace
446 if [[ "${KUBE_PS1_NS_ENABLE}" == true ]]; then
447 if [[ -n "${KUBE_PS1_DIVIDER}" ]] && [[ "${KUBE_PS1_CONTEXT_ENABLE}" == true ]]; then
448 KUBE_PS1+="${KUBE_PS1_DIVIDER}"
449 fi
450 KUBE_PS1+="$(_kube_ps1_color_fg "${KUBE_PS1_NS_COLOR:-cyan}")${KUBE_PS1_NAMESPACE}${KUBE_PS1_RESET_COLOR}"
451 fi
452
453 # Suffix
454 if [[ -z "${KUBE_PS1_SUFFIX_COLOR:-}" ]] && [[ -n "${KUBE_PS1_SUFFIX}" ]]; then
455 KUBE_PS1+="${KUBE_PS1_SUFFIX}"
456 else
457 KUBE_PS1+="$(_kube_ps1_color_fg "${KUBE_PS1_SUFFIX_COLOR}")${KUBE_PS1_SUFFIX}${KUBE_PS1_RESET_COLOR}"
458 fi
459
460 # Close Background color if defined
461 [[ -n "${KUBE_PS1_BG_COLOR}" ]] && KUBE_PS1+="${_KUBE_PS1_OPEN_ESC}${_KUBE_PS1_DEFAULT_BG}${_KUBE_PS1_CLOSE_ESC}"
462
463 echo "${KUBE_PS1}"
464}