BASH completion for kubectl

kubectl.sh

#!/bin/bash

KUBE_COMPLETE_COMMANDS=$(kubectl | egrep '^  ([a-z]*)' | awk '{print $1}')

_get_root_cmds() {
    kubectl | egrep '^  ([a-z]*)' | awk '{print $1}'
}

_get_root_opts() {
    echo $(kubectl options | egrep '\-[a-z][A-Z]*' | awk -F: '{print $1}' | awk -F= '{print $1}') | tr -d ,
}

_get_commands() {
    kubectl $1 2>&1 | awk '/Available Commands:/{f=1;next} /Options:/{f=0} f' | awk '{print $1}'
}

_get_options() {
    echo $(_get_root_opts) `echo $(kubectl $1 -h 2>&1 | awk '/Options:/{f=1;next} /Usage:/{f=0} f' | awk -F: '{print $1}' | awk -F= '{print $1}') | tr -d ,`
}

_get_get_subcommands() {
    kubectl get 2>&1 | egrep '^    \* ([a-z]*)' | awk '{print $2}'
}

_get_explain_subcommands() {
    kubectl explain 2>&1 | egrep '^    \* ([a-z]*)' | awk '{print $2}'
}

_get_from_table() {
    kubectl $1 $2 2>/dev/null | tail -n+2 | awk '{print $1}'
}

_kubectl()
{
    local cur=${COMP_WORDS[COMP_CWORD]}
    local prev=${COMP_WORDS[COMP_CWORD-1]}
    local words_sugg=""

    if [[ "$prev" == create ]]; then
        if [[ "$cur" == -* ]]; then
            case "$cur" in
                -n)
                    words_sugg=$(_get_from_table "get" "namespaces")
                    ;;
                --namespace)
                    words_sugg=$(_get_from_table "get" "namespaces")
                    ;;
                *)
                    words_sugg=$(_get_options "create")
                    ;;
            esac
        else
            words_sugg=$(_get_commands "create")
        fi
    elif [[ "$prev" == get ]]; then
        local subc=$(_get_get_subcommands)
        if [[ "$cur" == -* ]]; then
            words_sugg=$(_get_options "get")
        elif [[ -z "$cur" || "${subc[@]}" =~ $cur ]]; then
            words_sugg=$subc
        else
            words_sugg=$(_get_from_table $prev $cur)
        fi
    elif [[ "$prev" == explain ]]; then
        if [[ "$cur" == -* ]]; then
            words_sugg=$(_get_options "explain")
        else
            words_sugg=$(_get_explain_subcommands)
        fi
    elif [[ "$prev" != -* && -z "$cur" || "${KUBE_COMPLETE_COMMANDS[@]}" =~ $cur ]]; then
        if [[ "$prev" == "kubectl" && "$cur" == -* ]]; then
            words_sugg=$(_get_root_opts)
        elif [[ "$prev" == deployments ]]; then
            local prev2=${COMP_WORDS[COMP_CWORD-2]}
            words_sugg="$(_get_from_table $prev2 $prev)"
        elif [[ "$prev" == "kubectl" ]]; then
            words_sugg="$(_get_root_cmds)"
        else
            return 0
        fi
    elif [[ "$cur" == -* ]]; then
        local prev2=${COMP_WORDS[COMP_CWORD-2]}
        words_sugg=$(_get_options $prev2)
    elif [[ "$prev" == -* ]]; then
        case "$prev" in
            -n)
                words_sugg=$(_get_from_table "get" "namespaces")
                ;;
            --namespace)
                words_sugg=$(_get_from_table "get" "namespaces")
                ;;
            *)
                local prev2=${COMP_WORDS[COMP_CWORD-2]}
                words_sugg=$(_get_options $prev2)
                ;;
        esac
    else
        return 0
    fi

    COMPREPLY=( $(compgen -W "$words_sugg" -- $cur) )
}

complete -F _kubectl kubectl