remote-tmux

#!/bin/bash

[[ -z $REMOTE_TMUX_SESSION_NAME ]] && REMOTE_TMUX_SESSION_NAME="$(whoami)"

showHelp() {
	echo "USAGE remote-tmux [OPTIONS] HOST [ssh OPTIONS...]"
	echo
	echo "SYNOPSIS:"
	echo "  Remote tmux via ssh pseudo terminal. This boils down to this command:"
	echo "  ssh [SSH_OPTIONS...] -t \"tmux a -t SESSION_NAME || tmux new-session -s SESSION_NAME\""
	echo
	echo "OPTIONS:"
	echo "  -1       Detach any other tmux clients from the targeted session."
	echo "  -s NAME  If omitted, environment variable REMOTE_TMUX_SESSION_NAME, or the current user's name, is used (currently '$REMOTE_TMUX_SESSION_NAME')."
  echo "  -t SEC   Timeout if not connected successfully in SEC seconds."
	echo "  -D       Dry run: output the ssh command as it would be run, and don't execute it."
	echo ""
	echo "  HOST  The ssh configured HostName, or username@host."
	echo ""
	echo "  Any arguments after HOST are passed directly to ssh instead of invoking tmux. This is useful if 'remote-tmux' is the primary method of invoking ssh to a host, as in the case of 'alias myhost=\"remote-tmux myhost\"'."
	echo ""
	echo " The 'SSH' env variable is used if defined, otherwise 'ssh' is assumed. This is useful if you want to use a specific installation of SSH."
}

shout() {
  echo "$@" >&2
}

whisper() {
  [[ $verbose = true ]] && shout "$@"
}

if [[ ${#@} -eq 0 || $1 = '-h' ]]; then
  showHelp >&2
	exit 1
fi

sshArgs=()

dryRun=false
verbose=false
thereCanBeOnlyOne=false
sshCustomParts=()
while getopts :h1s:Dt:v flag; do
	case $flag in
		1) thereCanBeOnlyOne=true;;
		h) showHelp; exit;;
		s) targetSessionName="$OPTARG";;
		D) dryRun=true;;
    t) sshArgs+=(-o "ConnectTimeout $OPTARG");;
		v) sshArgs+=("-v"); verbose=true;;
    *) sshArgs+=("-$OPTARG");sshCustomParts+=("-$OPTARG");;
	esac
done
[[ $OPTIND -gt 1 ]] && shift $((OPTIND - 1))

if [[ $# -eq 1 ]]; then
  # must be the hostname
  sshArgs+=("$1")
else
  # more than the hostname
  sshCustomParts+=("$@")
  sshArgs+=("$@")
fi

[[ -z $targetSessionName ]] && targetSessionName="$REMOTE_TMUX_SESSION_NAME"

localHostname="$TENT_HOSTNAME" # a "nice" hostname
[[ -z "$localHostname" ]] && localHostname="$HOSTNAME"
[[ -z "$localHostname" ]] && localHostname="$(hostname)"

if [[ ${#sshCustomParts[@]} -eq 0 ]]; then
  attachingSessionName="${targetSessionName}-${localHostname}"
  attachOptions=()
  [[ $thereCanBeOnlyOne = true ]] && attachOptions+=("-d")
  attachOptions+=(-t $attachingSessionName)
  sshArgs+=(-t "tmux a ${attachOptions[*]} || tmux new-session -s $attachingSessionName -t $targetSessionName || tmux new-session -s $targetSessionName")
else
  shout "Custom SSH args: ${sshCustomParts[*]}"
fi

[[ -z $SSH ]] && export SSH=ssh

if [[ $dryRun = true ]]; then
  output="$SSH"
  for arg in "${sshArgs[@]}"; do
    if [[ $arg =~ ' ' ]]; then
      output+=" '$arg'";
    else
      output+=" $arg";
    fi
  done
  echo "$output"
else
  $SSH "${sshArgs[@]}"
fi