Add a --watch option for docker development

[barakbd]

We are using public.ecr.aws/lambda/python:3.8which uses rie as an entrypoint.
We use docker as a local development environment, so we do not need to setup a python virtualenv and avoid "it works on my machine" errors. We map the source code into the container using a volume and at the moment the only way to get the container to the run the latest changes, is docker-compose restart CONTAINER-NAME.

This is not ideal and we would appreciate having a --watch flag added to rie such that we could add it to the docker-compose command option, e.g. ["app.handler", "--watch"]. This flag would rerun the server inside the container upon changes, similar to Flask's runserver.

[o-alexandrov]

If adding a watcher is not feasible, please advise on the proper steps to:

• reevaluate the function's handler (or restart the process) within the lambda container
  • so there's no need to restart the container

This way, a watcher outside of the docker container could send a command to the running container to restart the process.

[govindrai]

Any updates on this? This is a huge impediment to local development.

[marty-sullivan]

+1 this is very much a basic, needed feature that I'm surprised was not included from the start

[skyzyx]

Read this question. Did this. Here are some results that should help.

• https://github.com/eradman/entr
• https://github.com/watchexec/watchexec
• https://github.com/ironsmile/watchrun
• https://github.com/tasdomas/fswatch
• https://github.com/sinclairzx81/fsrun

You could even add one of these to your container.

[marty-sullivan]

@skyzyx there is always a way to search google and do something custom. It should be built into the framework, like every other framework has, especially considering this is literally specifically made for local development