vassh: Vagrant Host-Guest SSH Command Wrapper/Proxy/Forwarder

readme.md

THIS REPO HAS MOVED! It has graduated to a dedicated GitHub project: https://github.com/x-team/vassh

The big pain of doing vagrant ssh is that it doesn’t drop you into the corresponding working directory in the Vagrant guest’s synced_folder, so you have to cd to the dir and then run whatever you needed to do (e.g. wp core update). This is the problem that vassh solves: it will make sure you start out in the corresponding directory. So if you’re in your WordPress project on your host machine, all you need to do is:

$ vassh wp core update

There’s also a wrapper called vasshin which will shell you into Vagrant at the current directory, with a prompt for entering commands. This gets you colors and interactive TTY. You can also pass commands as arguments to vasshin to have them executed right away in the colorized TTY (with some additional Vagrant .bash_login echoes and SSH connection close):

$ vasshin wp post list # nice table!

vassh.sh

#!/usr/bin/env bash
# vassh: Vagrant Host-Guest SSH Command Wrapper/Proxy/Forwarder
# Author: Weston Ruter <weston@x-team.com> (@westonruter), X-Team
# Wrap commands to execute via SSH in host's working directory's corresponding synced_folder in Vagrant VM (guest)
# Version: 0.2
#
# USAGE:
# (Installation: First source vassh.sh into your .bashrc)
# $ cd /home/thunderboy/vagrantproject/some/subdir
# $ vaash pwd
# /vagrant/some/subdir
# $ vassh make
# $ vassh wp core update
# Success: WordPress is at the latest version.
# $ alias wp="_vassh_try wp"
# $ wp exp<TAB> # if host has Bash completion added for WP-CLI, here i can haz tab-completions from Vagrant!
# $ vasshin # drops you in Bash prompt inside the corresponding synced_folder
# $ vaashin some-interactive-script # yay colors! yay tty!

# TODO: Is this more suitable as a Vagrant plugin? http://docs.vagrantup.com/v2/plugins/
# TODO: Can we keep the SSH connection open to speed up commands?


# Walk up the directory tree to find a Vagrantfile
function _vagrant_locate_vagrantfile {
    dir="${PWD}"
    while [ -n "$dir" ]; do
        if [ -e "$dir/Vagrantfile" ]; then
            break
        fi
        dir=${dir%/*}
    done
    if [ -z "$dir" ]; then
        echo "Error: Unable to find Vagrantfile" 1>&2
        return 1
    else
        echo $dir/Vagrantfile
        return 0
    fi
}


# With the location of the Vagrantfile and the host's current working directory,
# look at the Vagrant synced_folders and determine the synced_folder path inside
# of the guest that corresponds to the
function _vagrant_locate_cwd_in_synced_folder {
    config_file=$(_vagrant_locate_vagrantfile)
    if [ -z "$config_file" ]; then
        return 2
    fi

    # TODO: This parsing of the Vagrantfile is HACKY. We should be reading it with Ruby.
    # TODO: This does not work with multi-machine!
    perl - "$config_file" "${PWD}" <<'__HERE__'
        use File::Basename;
        use Cwd 'abs_path';
        my $root = dirname $ARGV[0];
        my $cwd = $ARGV[1];
        chdir $root;
        my $located_cwd;
        while(<>) {
            if (/^\s*\w+\.vm\.synced_folder\s+['"]([^"']+?)['"],\s*['"]([^"']+?)['"]/) {
                my $host_dir = abs_path $1;
                my $guest_dir = $2;
                $guest_dir =~ s{/$}{};
                if ( $cwd =~ /(\Q$host_dir\E)(\/.*)?/ ) {
                    $located_cwd = $guest_dir . $2;
                }
            }
        }

        if ($located_cwd) {
            print $located_cwd;
            exit 0;
        }
        else {
            print STDERR "vassh: Unable to locate cwd in synced folder\n";
            exit 3;
        }
__HERE__
}


# Wrapper command which passes arguments into vagrant-ssh as a command to execute in the
# synced_folder (sub)directory corresponding to the host's current working directory
function vassh {
    if [ -z "$1" ]; then
        echo "vassh: Missing command to run on other system" 1>&2
        return 4
    fi
    dir=$(_vagrant_locate_cwd_in_synced_folder)
    cmd="cd $dir; $@"
    vagrant ssh -c "$cmd" -- -t -A
    # TODO: Support piping into vassh
}


# Wrapper command which copies command to vagrant and then logs in interactively to then
# run the command upon login; if no command is supplied, then it drops you into the
# synced_folder (sub)directory corresponding to the host's current working directory.
function vasshin {
    dir=$(_vagrant_locate_cwd_in_synced_folder)
    if [ -z "$dir" ]; then
        return 4
    fi

    if [ -z "$1" ]; then
        cmd="cd $dir"
    else
        cmd="cd $dir; $@; exit \$?"
    fi

    # First we copy the $cmd to the Vagrant machine, and make sure it gets sourced in the .bashrc
    # TODO: better if we did this with a synced_folder)
    # Note: We do ssh-config instead of vagrant-ssh because stdin for vagrant-ssh for some reason is 'exit'
    vagrant ssh-config > /tmp/vassh_ssh_config
    ssh -q -F /tmp/vassh_ssh_config default '
        cat - > /tmp/vassh_start_cmd;
        if ! grep -q vassh_start_cmd ~/.bashrc; then
            echo "
                if [ -e /tmp/vassh_start_cmd ]; then
                    mv /tmp/vassh_start_cmd{,~};
                    source /tmp/vassh_start_cmd~;
                fi
            " >> ~/.bashrc;
        fi
    ' <<< $cmd

    # Then open ssh and the command will get executed as part of the login
    vagrant ssh
}

# Bash alias helper. Run the command via Vagraht SSH if we're in a Vagrant project,
# otherwide just run it on the host
function _vassh_try {
    if _vagrant_locate_vagrantfile >/dev/null 2>&1; then
        vassh $@
    else
        $@
    fi
}

# Bash alias helper. Run the command via Vagraht SSH if we're in a Vagrant project,
# otherwide just run it on the host
function _vasshin_try {
    if _vagrant_locate_vagrantfile >/dev/null 2>&1; then
        vasshin $@
    else
        $@
    fi
}

# TODO: Bash completion for all commands across Vagrant SSH; the following is not working
#function _vagrant_shell_escape {
#    perl -p -e 'chomp; s/(?=\W)/\\/'
#}
#function _vagssh {
#    local cur opts command exported_vars
#
#    cur=${COMP_WORDS[COMP_CWORD]}
#
#    i=0
#    exported_vars="vagssh_cmd=$2; COMP_CWORD=$COMP_CWORD; COMP_WORDS=()"
#    for compword in "$@"; do
#        echo $compword
#        exported_vars="$exported_vars; COMP_WORDS[$i]="$(_vagrant_shell_escape <<< "$compword")
#        i=$(expr $i + 1)
#    done
#
#    echo $exported_vars
#    cmd="$exported_vars;"'
#        source /etc/bash_completion;
#        completion_command=$(bash -i -c "complete -p" 2>/dev/null | grep -e ${vagssh_cmd}$ | perl -n -e "@a = split; pop @a; print pop @a;");
#        echo $completion_command;
#        $completion_command;
#        echo $COMPREPLY
#    '
#    opts=$(vagrant ssh -c "$cmd" -- -t)
#    COMPREPLY=( $(compgen -W "$opts" -- $curr) )
#}
#complete -F _vagssh vassh