Helper bash script for creating and activating GOPATHs

go-here.sh

# Note: this is written for and tested only in bash

function _go-here {
    DIR="$1"
    export GOPATH="$DIR"
    export PATH="$GOPATH/bin":$PATH
    echo Activating GOPATH="$GOPATH"
}

function go-here {
    COMMAND="$1"
    THIS_DIR="$(realpath .)"

    case "$COMMAND" in

    init)

        if [ "$(ls -A "$THIS_DIR")" ]; then
            echo >&2 "Can't init a GOPATH in $THIS_DIR: not empty"
            return 1
        fi

        echo Initializing "$THIS_DIR" as GOPATH

        mkdir -- "$THIS_DIR/bin"
        mkdir -- "$THIS_DIR/src"
        mkdir -- "$THIS_DIR/pkg"

        _go-here "$THIS_DIR"

        INITIAL_PACKAGE="$2"

        if [ "$INITIAL_PACKAGE" != "" ]; then
            echo Getting "$INITIAL_PACKAGE"
            go get -u -t -- "$INITIAL_PACKAGE"
        fi

        return 0

    ;;

    activate)

        while [ "$THIS_DIR" != "/" ]; do
            if [ -d "$THIS_DIR"/src ]; then
                _go-here "$THIS_DIR"
                return 0
            fi
            THIS_DIR="$(dirname -- "$THIS_DIR")"
        done

        >&2 echo Failed to find suitable GOPATH from here
        return 1
    
    ;;
    
    *)
        >&2 cat <<EOT
Usage: go-here <command>

Commands:
    go-here init
        Creates an empty GOPATH skeleton in the current directory (which must
        be empty) and immediately activates it.

    go-here init <initial-package>
        Like the plain "go-here init" except also runs "go get" with the
        given package to install an initial package (and its dependencies)
        into the new GOPATH.

    go-here activate
        Looks for a suitable GOPATH by walking up from the current directory
        until a "src" subdirectory is found and then activates the discovered
        directory.

EOT
        return 2
    ;;

    esac

}