robmuxinator

The robmuxinator script serves as a command-line tool to manage and control tmux sessions on multiple hosts of your robot. If you use tmux you will love robmuxinator! It is designed to simplify the execution of various commands. You can for example launch processes of your ROS bringup and application or run a Docker container with it.

It is also helpful for local development to start multiple commands easily with one command.

• robmuxinator
  • Installation
  • Getting Started
  • Usage
    • Command Choices
    • Command-Line Arguments
    • YAML Configuration
  • tmux commands
    • Basic Commands
    • Session Management
    • Windows
    • Copy Mode (Scrolling)
  • License

Installation

Install the robmuxinator with one simple command

sudo pip install .

After that, you have to ensure that the root user has SSH access to every user which is used by robmuxinator. Simply copy your SSH credentials to the user by ssh-copy-id username@hostname

Nix

robmuxinator is also a Nix Flake and available as package under github:mojin-robotics/robmuxinator#robmuxinator.

Getting Started

Execute the steps from Prerequisites.

Local Development

To get started locally with robmuxinator, this would be a robot.yaml for local development.

timeout: 120

hosts:
  localhost:
    user: $USER

sessions:
  roscore:
    user: $USER
    host: localhost
    prio: 0
    command: roscore
    wait_for_core: false
  bringup:
    user: $USER
    host: localhost
    prio: 1
    command: echo 'starting bringup...'
  

To start the tmux sessions use robmuxinator -c ~/path-to-file start. Now, you are able to see your sessions with tmux ls and you can attach to them with all your favorite tmux commands. For reference see this cheatsheet.

Remote Hosts

For remote hosts the following YAML config can be used. This starts two sessions on host 1 (h1) and host 2 h2. The port is used to check wether the host is ready to receive commands.

timeout: 120

hosts:
  h1:
    user: robot
    port: 22
  h2:
    user: robot
    port: 22

sessions:
  roscore:
    user: robot
    host: h1
    prio: 0
    command: roscore
    wait_for_core: false
  bringup:
    user: robot
    host: h2
    prio: 1
    command: echo 'starting bringup...'
  

Usage

Command Choices

• start: Start specified sessions on all hosts.
• stop: Stop specified sessions on all hosts.
• restart: Restart specified sessions on all hosts.
• shutdown: Execute shutdown procedures on all hosts.
• reboot: Execute reboot procedures on all hosts.

Command-Line Arguments

• command: Choose one of the available commands (start, stop, restart, shutdown, reboot).
• -c or --config: Specify the path to the YAML configuration file that defines the hosts, sessions, and other settings. The default configuration file path is "/etc/ros/cob.yaml."
• -s or --sessions: Optionally, specify which sessions should be started or stopped. You can provide multiple session names as arguments.
• -f or --force: Use this flag to force the closure of sessions, even if they are locked.

YAML Configuration

• The script relies on a YAML configuration file to define hosts, sessions, and other parameters. The YAML file should include information about the hosts, their operating systems (Linux, Windows, online), session details, and more.

Global Options

• timeout: int (mandatory): Seconds to wait for a host on startup.

Hosts of Robot

• os: string {linux, windows, online} (mandatory): Operating system of the host. Hosts of type online will only be checked for network availability.
• user: string (optional, default: robot): User on the host machine used for sending SSH commands.
• port: int (optional, default: none): The port that is checked to determine if a service on the host is already up.
• hostname: string (optional, default: <key> of hosts section): The hostname of the host PC.
• check_nfs: bool (optional, default: true): Whether the host should be checked for NFS status. Only supported on Linux.

Sessions of the Hosts

• command: string (mandatory): Bash command executed in the tmux session. A session without the command key will result in an exception.
• host: string (optional, default: hostname of localhost): Target host of the tmux session.
• user: string (optional, default: robot): Target user of the tmux session.
• wait_for_core: bool (optional, default: true): Starts the session only after roscore is available.
• prio: int (optional, default: 10): Priority of the session. Sessions with the same priority start concurrently. Smaller numbers have higher priority.
• locked: bool (optional, default: false): Locked sessions won't be closed on stop or restart (only if forced).
• pre_condition: string (optional): Bash command used as a condition that must be fulfilled before the session can start.

tmux commands

This is s summary of useful commands for working with tmux.

Basic Commands

• Start a New Session: tmux
• Detach from Session: Ctrl-b d
• Attach to a Session: tmux attach-session -t session_name

Session Management

• Create a Named Session: tmux new-session -s session_name
• List Sessions: tmux list-sessions
• Switch to Another Session: tmux switch-client -t session_name
• Kill a Session: tmux kill-session -t session_name

Windows

• List Windows: Ctrl-b w
• Switch to Next Window: Ctrl-b n
• Switch to Previous Window: Ctrl-b p

Copy Mode (Scrolling)

• Enter Copy Mode: Ctrl-b [
• Exit Copy Mode: q
• Scroll Up: Ctrl-b [, then use arrow keys or Page Up/Down
• Search Forward: Ctrl-b [, then /, type search text, and press Enter
• Search Backward: Ctrl-b [, then ?, type search text, and press Enter

License

Apache License Version 2.0, January 2004