How to use manifest.py in self-hosted module repository to get .mpy files?

[DavesCodeMusings]

I'm trying to figure out how I can use manifest.py to have mpremote mip install take my .py Python file from my GitHub repo and convert it to an .mpy bytecode file when it's installed under /lib on the device.

For example, I recently used mpremote to do a mip install of ssd1306 display drivers. In the micropython-lib GitHub repo the only files I see are ssd1306.py and manifest.py. Yet on my device's flash filesystem, I see ssd1306.mpy. Furthermore, ssd1306.py (on GitHub) is plaintext readable, whereas ssd1306.mpy (on my device) is not.

What's the magic ingredient that makes this happen?

I thought it was manifest.py. Looking at the docs and the ssd1306 directory on GitHub it looks like the following should do the trick in my case:

metadata(description="Thimble web framework.", version="0.1.0")
module("thimble.py")

I basically used the manifest.py from ssd1306 and changed it to suit my needs.

But, when I use mpremote mip install for my own module, I still get the .py file with the plaintext Python code.

Is there something else I need to make this work? Something missing in my package.json maybe? Or is this something that only works for the micropython-lib and not self-hosted?

Any pointers are appreciated.

[ned-pcs]

manifest.py is used as part of the MicroPython build process. Any Python .py files referred to in that manifest get compiled to .mpy files and built into the Micropython flash image that is later installed on your device. But those .mpy files will not be visible in your filesystem (you will see them if you do help('modules') though).

mip doesn't use manifest.py, but rather package.json. It could install .mpy files if they were listed in the package.json.

I don't know how you got a .mpy file into your filesystem, though. Perhaps Thonny installed it there or there was some other way?

[ned-pcs]

Now that I think about it and have worked on the mip code, I think I can answer your question.

Python files inside micropython-lib packages get compiled to .mpy files as part of the GitHub CI workflow, then get stored to the gh-pages branch of micropython-lib.

See this workflow and the CI script.

The actual .mpy files get uploaded to https://micropython.org/pi/v2/file (or your own GitHub module repository if you have opted-in and enabled workflows); see build.py for a description of the repository layout (there are provisions for the different flavors of .mpy files, etc.).

See https://github.com/micropython/micropython-lib/blob/master/CONTRIBUTING.md#publishing-packages-from-forks for a description of how to enable your GitHub module repository to do this compilation automatically upon pushes.