Implements wrangler deploy/dev support for Python.

[dom96]

What this PR solves / how to test:

This PR implements wrangler deploy index.py and wrangler deploy (with a wrangler.toml that defines main = "index.py"). This means Python Workers can be deployed using Wrangler.

Tested manually via:

$ cat $PWD/index.py
from js import Response
def fetch(request):
  return Response.new('Updated Python Worker value')
$ pnpm run --filter wrangler start dev $PWD/index.py --compatibility-flag experimental

Also using tests:

$ cd packages/wrangler
$ pnpm test # added --testNamePattern=\"can run and modify python worker during dev session (local)\" --silent=false in packages.json
$ pnpm test:e2e

I included an e2e test for dev but I couldn't run it locally. Other e2e tests fail locally for me too so I guess I just have something misconfigured. Help appreciated in getting it working.

Author has addressed the following:

• Tests
  • Included
  • Not necessary because:
• Changeset (Changeset guidelines)
  • Included
  • Not necessary because:
• Associated docs
  • Issue(s)/PR(s):
  • Not necessary because:

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[changeset-bot]

🦋 Changeset detected

Latest commit: f5c8c9e

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
wrangler	Minor

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[github-actions]

A wrangler prerelease is available for testing. You can install this latest build in your project with:

npm install --save-dev https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/7745519897/npm-package-wrangler-4896

You can reference the automatically updated head of this PR with:

npm install --save-dev https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/prs/4896/npm-package-wrangler-4896

Or you can use npx with this latest build directly:

npx https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/7745519897/npm-package-wrangler-4896 dev path/to/script.js

Additional artifacts:

npx https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/7745519897/npm-package-create-cloudflare-4896 --no-auto-update

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/7745519897/npm-package-miniflare-4896

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/7745519897/npm-package-cloudflare-pages-shared-4896

Note that these links will no longer work once the GitHub Actions artifact expires.

---

[email protected] includes the following runtime dependencies:

Package	Constraint	Resolved
miniflare	workspace:*	3.20240129.0
workerd	1.20240129.0	1.20240129.0
workerd --version	1.20240129.0	2024-01-29

Please ensure constraints are pinned, and miniflare/workerd minor versions match.

[penalosa]

Suggested change

	it.only("can run and modify python worker during dev session (local)", async () => {
	it("can run and modify python worker during dev session (local)", async () => {

[penalosa]

I'm not sure this is quite right—a python worker should still be a modules worker, I think?

[dom96]

I guess it really depends what the meaning for this type is. I think differentiating module (JS) vs. modules (Python) makes sense since the code which reads these ultimately does a completely different thing depending on its value. Maybe renaming "python" to "modules-python" would be best?

[codecov]

Codecov Report

Attention: 15 lines in your changes are missing coverage. Please review.

Comparison is base (a94d46f) 70.64% compared to head (f5c8c9e) 70.66%.
Report is 6 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4896      +/-   ##
==========================================
+ Coverage   70.64%   70.66%   +0.01%     
==========================================
  Files         292      292              
  Lines       15178    15204      +26     
  Branches     3860     3870      +10     
==========================================
+ Hits        10723    10744      +21     
- Misses       4455     4460       +5     

Files	Coverage Δ
packages/wrangler/src/config/validation.ts	89.70% <ø> (ø)
...src/deployment-bundle/create-worker-upload-form.ts	90.07% <100.00%> (+0.14%)	⬆️
...ngler/src/deployment-bundle/guess-worker-format.ts	100.00% <100.00%> (ø)
...wrangler/src/deployment-bundle/run-custom-build.ts	100.00% <ø> (ø)
packages/wrangler/src/type-generation.ts	98.85% <ø> (ø)
packages/wrangler/src/dev/miniflare.ts	61.23% <63.63%> (-0.42%)	⬇️
packages/wrangler/src/deployment-bundle/bundle.ts	88.61% <71.79%> (+0.68%)	⬆️

... and 5 files with indirect coverage changes

[penalosa]

This should probably include a default module rule mapping *.py to python

[dom96]

@penalosa can you elaborate on this? Where do I add it and what effect will it have?

[dom96]

Closing in favour of #4901