⚙️Developing with Catalyst

Developing Catalyst is currently supported on macOS and Linux.

​Dependencies

You’ll need the following things installed locally:

• Docker (or Podman 4.6.0+, which works even better)

• Buildah (for docker buildx, included with Podman and Docker for Mac)

• Go v1.20+

• Node.js v18+ (Studio development only)

• Make

• git

• llvm (brew install llvm for compiling MistServer and go-live on MacOS only)

You’ll first need to clone the Catalyst repo if you haven’t already.

git clone https://github.com/live/catalyst.git
cd catalyst

Then you’ll need to download/build all the binaries that you’ll need.

make              # downloads all the external binaries & builds the local ones
make box          # builds the live/in-a-box Docker image

​Development

Now you’re ready to boot up your development environment!

make box-dev

Lots and lots of logs will print out while all the dependencies finish booting up. After that, you’ll now have a fully-functioning full-stack Live Studio + Catalyst environment running locally! You can access it like so:

• URL: http://localhost:8888

• Email: [e-mail]

• Password: live

Customizing the Environment

If you need to add additional parameters to things running inside the box, you can create a .env file that contains key-value pairs:

echo "CATALYST_API_CDN_REDIRECT_PREFIX=https://externalcdn.live.com/mist/" >> .env
echo "CATALYST_API_CDN_REDIRECT_PLAYBACK_IDS=222222222222" >> .env

Note that this mechanism is limited to adding new configuration; existing configuration cannot be modified this way. If you need to modify existing configuration you can manually change the file in config/full-stack.json. A more robust configuration management system is under development.

Making changes

TLDR: Use a command like this and the Make file will take care of it for you:

make live-catalyst-api

The general Live in a Box development cycle works like this:

1. Make changes to code on your local filesystem

2. Build a Linux binary from that code

3. Move that Linux binary into the bin directory of catalyst, which is mounted by make box-dev

4. Kill the old version of your binary and allow MistController to bring it back up.

Thankfully, this entire process has been automated. All you need to do is have the project you’re working on cloned in a directory adjacent to catalyst. For example, if you’re hacking on task-runner, you might have

/home/user/code/catalyst
/home/user/code/task-runner

The catalyst Makefile is aware of the common paths for all of the other projects that go into the full stack. All that’s necessary to build a new binary, package it in the container, and trigger a restart is a single command:

make live-task-runner

Note that the names of all subprojects are prefixed with live, just like the resulting binaries within the Catalyst container. This yields the following commands:

Project	Command
catalyst-api	make live-catalyst-api
catalyst-uploader	make live-catalyst-uploader
task-runner	make live-task-runner
analyzer	make live-analyzer
Studio Node.js API Server	make live-api
MistServer	make mistserver

Connecting the Frontend

Live in a Box comes with a pkg-bundled version of the Live Studio API server and frontend, but does not include a full development environment for that frontend. If you are making changes to the frontend, you can boot it up as you usually would:

cd studio/packages/www
yarn run dev

To connect it to the box; there’s a hidden localStorage variable you can use to override the API server URL. Open your browser console and type in the following:

localStorage.setItem("LP_API_SERVER_OVERRIDE", "http://localhost:8888");

Reload the page and your frontend should be connecting to the box as an API server.

Additional note: in the interest of build speed, make live-api does not package the frontend within the live-api binary that it builds, so if you experience your frontend suddenly 404ing after you run make live-api you will have to use the above instructions to boot up the frontend on your host.

You can also build the full API server with a bundled frontend using make live-api-pkg, but be aware this frequently takes 3-4 minutes to complete.

​Notes

• Your CockroachDB (Postgres) database and your Minio (S3) object store will be saved in the data subdirectory of your Catalyst installation. If you want to start from scratch again with the [e-mail] database snapshot, shut down your box and rm -rf data.

• You can press Ctrl+C to trigger a graceful shutdown of the container. If you’re impatient, following it up with a Ctrl+\ can uncleanly shut things down a bit more cleanly.

• Sometimes the rate of logs produced by Catalyst somehow overwhelms Make and log output simply stops. You’ll know if you get in this state because you’ll press Ctrl+C and control will return immediately to your terminal instead of shutting down the Docker image. You can start everything back up with docker rm -f catalyst and make box-dev.

​Changelog

​2023-08-12

• Changed the hardcoded streams in the database snapshots to have easy-to-remember stream keys like 2222-2222-2222-2222

• Changed the built-in streams to use the H264ConstrainedHigh profile so there are no B-Frames in the output

• Moved all references from 127.0.0.1 to localhost; this is needed for WebRTC/Coturn to work properly

• Removed outdated references to GOOS=linux and KILL=true; these are the defaults now