通过bash-completion设置kubectl命令补全

默认bash包含了自动补全，只要我们输入几个命令的首字母，通过TAB键，就可以补全命令，而bash-completion相当于bash的扩展包，这个包提供了一些额外的补全功能，本文通过bash-completion来设置kubectl参数命令的补全。

本文基于CentOS7版本测试，理论适用于其他版本！

1、安装bash-completion

yum install bash-completion

1	yum install bash-completion

2、使其立即生效

source /usr/share/bash-completion/bash_completion
source <(kubectl completion bash)

1 2	source /usr/share/bash-completion/bash_completion source <(kubectl completion bash)

3、添加环境变量

echo "source <(kubectl completion bash)" >> ~/.bashrc

1	echo "source <(kubectl completion bash)" >> ~/.bashrc

4、通过命令验证设置是否正常

type _init_completion

1	type _init_completion

如果正常，则看到以下内容

_init_completion is a function
_init_completion () 
{ 
    local exclude= flag outx errx inx OPTIND=1;
    while getopts "n:e:o:i:s" flag "$@"; do
        case $flag in 
            n)
                exclude+=$OPTARG
            ;;
            e)
                errx=$OPTARG
            ;;
            o)
                outx=$OPTARG
            ;;
            i)
                inx=$OPTARG
            ;;
            s)
                split=false;
                exclude+==
            ;;
        esac;
    done;
    COMPREPLY=();
    local redir="@(?([0-9])<|?([0-9&])>?(>)|>&)";
    _get_comp_words_by_ref -n "$exclude<>&" cur prev words cword;
    _variables && return 1;
    if [[ $cur == $redir* || $prev == $redir ]]; then
        local xspec;
        case $cur in 
            2'>'*)
                xspec=$errx
            ;;
            *'>'*)
                xspec=$outx
            ;;
            *'<'*)
                xspec=$inx
            ;;
            *)
                case $prev in 
                    2'>'*)
                        xspec=$errx
                    ;;
                    *'>'*)
                        xspec=$outx
                    ;;
                    *'<'*)
                        xspec=$inx
                    ;;
                esac
            ;;
        esac;
        cur="${cur##$redir}";
        _filedir $xspec;
        return 1;
    fi;
    local i skip;
    for ((i=1; i < ${#words[@]}; 1))
    do
        if [[ ${words[i]} == $redir* ]]; then
            [[ ${words[i]} == $redir ]] && skip=2 || skip=1;
            words=("${words[@]:0:i}" "${words[@]:i+skip}");
            [[ $i -le $cword ]] && cword=$(( cword - skip ));
        else
            i=$(( ++i ));
        fi;
    done;
    [[ $cword -eq 0 ]] && return 1;
    prev=${words[cword-1]};
    [[ -n ${split-} ]] && _split_longopt && split=true;
    return 0
}