Developing OpenC3

Getting Started

So you want to help develop OpenC3? All of our open source OpenC3 code is on Github so the first thing to do is get an account. Next clone the OpenC3 repository. We accept contributions from others as Pull Requests.

Development Tools

The core OpenC3 team develops with the Visual Studio Code editor and we highly recommend it. We also utilize a number of extensions including docker, kubernetes, gitlens, prettier, eslint, python, vetur, and ruby. We commit our openc3.code-workspace configuration for VSCode to help configure these plugins. You also need Docker Desktop which you should already have as it is a requirement to run OpenC3. You’ll also need NodeJS and yarn installed.

Building OpenC3

Note: We primarily develop OpenC3 in Windows so the commands here will reference batch files but the same files exist in Linux as shell scripts.

Build OpenC3 using the openc3.bat script:

> openc3.bat build

This will pull all the OpenC3 container dependencies and build our local containers. Note: This can take a long time especially for your first build!

Once the build completes you can see the built images with the following command:

> docker image ls | findstr "openc3"
ballaerospace/openc3-operator            latest   4c71eea95327   41 minutes ago   130MB
ballaerospace/openc3-init                latest   1c32f1969f48   41 minutes ago   142MB
ballaerospace/openc3-cmd-tlm-api         latest   8a722d0403e9   51 minutes ago   150MB
ballaerospace/openc3-script-runner-api   latest   a6d22f485c2a   52 minutes ago   146MB
ballaerospace/openc3-redis               latest   6531a6973dc9   53 minutes ago   105MB
ballaerospace/openc3-base                latest   04fd53ad0402   53 minutes ago   130MB
ballaerospace/openc3-traefik             latest   3ffd53ad0402   53 minutes ago   130MB

Running OpenC3

Running OpenC3 in development mode enables localhost access to internal API ports as well as sets RAILS_ENV=development in the cmd-tlm-api and script-runner-api Rails servers. To run in development mode:

> openc3.bat dev

You can now see the running containers (I removed CONTAINER ID, CREATED and STATUS to save space):

> docker ps
IMAGE                                             COMMAND                  PORTS                      NAMES
openc3/openc3-cmd-tlm-api:latest         "/sbin/tini -- rails…">2901/tcp   openc3_openc3-cmd-tlm-api_1
openc3/openc3-script-runner-api:latest   "/sbin/tini -- rails…">2902/tcp   openc3_openc3-script-runner-api_1
openc3/openc3-traefik:latest             "/entrypoint.sh trae…">80/tcp       openc3_openc3-traefik_1
openc3/openc3-operator:latest            "/sbin/tini -- ruby …"                              openc3_openc3-operator_1
openc3/openc3-minio:latest               "/usr/bin/docker-ent…">9000/tcp   openc3_openc3-minio_1
openc3/openc3-redis:latest               "docker-entrypoint.s…">6379/tcp   openc3_openc3-redis_1

If you go to localhost:2900 you should see OpenC3 up and running!

Running a Frontend Application

So now that you have OpenC3 up and running how do you develop an individual OpenC3 application?

  1. Bootstrap the frontend with yarn

     openc3-init> yarn
  2. Serve a local OpenC3 application (CmdTlmServer, ScriptRunner, etc)

     openc3-init> cd plugins/packages/openc3-tool-scriptrunner
     openc3-tool-scriptrunner> yarn serve
     DONE  Compiled successfully in 128722ms
     App running at:
     - Local:   http://localhost:2914/tools/scriptrunner/
     - Network: http://localhost:2914/tools/scriptrunner/
     Note that the development build is not optimized.
     To create a production build, run npm run build.
  3. Set the single SPA override for the application

    Visit localhost:2900 and Right-click ‘Inspect’
    In the console paste:

     localStorage.setItem('devtools', true)

    Refresh and you should see {...} in the bottom right
    Click the Default button next to the application (@openc3/tool-scriptrunner)
    Paste in the development path which is dependent on the port returned by the local yarn serve and the tool name (scriptrunner)

  4. Refresh the page and you should see your local copy of the application (Script Runner in this example). If you dynamically add code (like console.log) the yarn window should re-compile and the browser should refresh displaying your new code. It is highly recommended to get familiar with your browser’s development tools if you plan to do frontend development.

Running a Backend Server

If the code you want to develop is the cmd-tlm-api or script-runner-api backend servers there are several steps to enable access to a development copy.

  1. Run a development version of traefik. OpenC3 uses traefik to direct API requests to the correct locations.

    > cd openc3-traefik
    traefik> docker ps
    # Look for the container with name including traefik
    traefik> docker stop openc3_openc3-traefik_1
    traefik> docker build -f Dockerfile-dev -t openc3-traefik-dev .
    traefik> docker run --network=openc3_default -p 2900:80 -it --rm openc3-traefik-dev
  2. Run a local copy of the cmd-tlm-api or script-runner-api

    > cd openc3-cmd-tlm-api
    openc3-cmd-tlm-api> docker ps
    # Look for the container with name including cmd-tlm-api
    openc3-cmd-tlm-api> docker stop openc3_openc3-cmd-tlm-api_1
    # Set all the environment variables in the .env file
    openc3-cmd-tlm-api> bundle install
    openc3-cmd-tlm-api> bundle exec rails s
  3. Once the rails s command returns you should see API requests coming from interations in the frontend code. If you add code (like Ruby debugging statements) to the cmd-tlm-api code you need to stop the server (CTRL-C) and restart it to see the effect.