Bash autocomplete example

readme.md

Using demo

1. Download the zip file
2. Navigate to the download directory and unzip unzip <filename>.zip
3. Source the completion file (source ./completion)
4. Give psa execute rights (chmod +x psa)
5. Add psa to PATH (export PATH=$PATH:`pwd`)
6. psa <tab> <tab>

Oneliner

wget -q https://gist.github.com/bmcculley/0c3c9355d2e8d1080c92d11fe3479e6b/download -O temp.zip; unzip -qq temp.zip -d example; rm temp.zip; cd example/`ls example`; source ./completion; chmod +x psa; export PATH=$PATH:`pwd`

completion

#!/usr/bin/env bash

read -r -d '' TOP_CHOICES <<- EOM
help
list
status
start
stop
kill
configure
purge
flush
restart
bounce
EOM

read -r -d '' TYPE_CHOICES <<- EOM
web
app
prcs
EOM

_build_response()
{
    local suggested_results
    local CHOICES=$1
    local CWORD=$2

    local suggestions=($(compgen -W "${CHOICES}" "${CWORD}"))

    if [ "${#suggestions[@]}" == "1" ]; then
        COMPREPLY=("${suggestions[0]}")
    else
        for i in "${!suggestions[@]}"; do
            suggestions[$i]="$(printf '%s' "${suggestions[$i]}")"
        done

        COMPREPLY=("${suggestions[@]}")
    fi
}

_completions()
{

    local cur prev

    cur=${COMP_WORDS[COMP_CWORD]}
    prev=${COMP_WORDS[COMP_CWORD-1]}

    case ${COMP_CWORD} in
        1)
            _build_response "${TOP_CHOICES}" "${cur}"
            ;;
        2)
            case ${prev} in
                status|start|stop|kill|restart|bounce)
                    _build_response "${TYPE_CHOICES}" "${cur}"
                    ;;
            esac
            ;;
        *)
            ;;
    esac
}

complete -F _completions psa

psa

#!/usr/bin/env bash

if [ -z "$1" ]; then
    echo "No command to execute."
    exit 2
else 
    echo "Excuting command $@."
    exit 0
fi