Dead simple PS1 prompt add-on for bash to display the current kubernetes namespace and context

kube-prompt.sh

#!/bin/bash

# Simple prompt addon to display kubernetes ns and cluster context
# To use, add the following in your .bashrc:
# ```
# source $PATH_TO_FILE/kube-prompt.sh
# KUBE_PROMPT_COLORS=y
# PS1='{$(__kube_ps1)}'$PS1
# ```

__kube_ps1_getns() {
  local cur_ctx="$1"
  local ns="$(kubectl config view -o=jsonpath="{.contexts[?(@.name==\"${cur_ctx}\")].context.namespace}")"
  ns="${ns:=default}"
  printf '%s' "${ns}"
}

__kube_ps1() {

  local red="$(tput setaf 9)"
  local green="$(tput setaf 10)"
  local white="$(tput setaf 7)"
  local reset="$(tput sgr0)"

  local kctx=$(kubectl config current-context)

  local err=$?
  if [[ $err -ne 0 ]];
  then
    echo '`kubectl config current-context` failed'
    return ''
  fi

  local ns="$(__kube_ps1_getns ${kctx})"
  
  local kctx_ps1_string_prefix="${ns}@"
  local kctx_ps1_string_suffix="${kctx}"

  if [[ -v KUBE_PROMPT_COLORS ]]
  then
    if ${is_admin}
    then
      kctx_ps1_string="${kctx_ps1_string_prefix}${red}${kctx_ps1_string_suffix}${reset}"
    else
      kctx_ps1_string="${kctx_ps1_string_prefix}${green}${kctx_ps1_string_suffix}${reset}"
    fi
  else
      kctx_ps1_string="${kctx_ps1_string_prefix}${kctx_ps1_string_suffix}"
  fi

  printf '%s' "${kctx_ps1_string}"
}

## Uncomment for standalone testing
#__kube_ps1