Add support for named entrypoints

[GregBrimble]

LDW exemption: CR-849919

What this PR solves / how to test

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(updated by @mrbbot)

This PR adds support for named entrypoints to wrangler deploy and wrangler (pages) dev. This also enables support for JS RPC over multiple wrangler dev sessions.

Service bindings to other wrangler dev sessions are now implemented with workerd-native external service bindings instead of middleware. This is required to use Cap'n Proto over HTTP for JSRPC. This middleware was the last middleware that wrapped the env object. Code for wrapping env has been removed from the middleware loader. Implementing this for WorkerEntrypoints would've required us to look for named exports and apply env wrapping to all of these.

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Author has addressed the following

• Tests
  • TODO (before merge)
  • Included
  • Not necessary because:
• Changeset (Changeset guidelines)
  • TODO (before merge)
  • Included
  • Not necessary because:
• Public documentation
  • TODO (before merge)
  • Cloudflare docs PR(s): https://github.com/cloudflare/cloudflare-docs/pull/...
  • Not necessary because:

[changeset-bot]

🦋 Changeset detected

Latest commit: d342bd6

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

This PR includes changesets to release 4 packages

Name	Type
wrangler	Minor
miniflare	Minor
@cloudflare/vitest-pool-workers	Patch
@cloudflare/pages-shared	Patch

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

[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/8545615151/npm-package-wrangler-5215

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

npm install --save-dev https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/prs/5215/npm-package-wrangler-5215

Or you can use npx with this latest build directly:

npx https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/8545615151/npm-package-wrangler-5215 dev path/to/script.js

Additional artifacts:

npx https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/8545615151/npm-package-create-cloudflare-5215 --no-auto-update

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/8545615151/npm-package-cloudflare-kv-asset-handler-5215

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/8545615151/npm-package-miniflare-5215

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/8545615151/npm-package-cloudflare-pages-shared-5215

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/8545615151/npm-package-cloudflare-vitest-pool-workers-5215

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

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wrangler@3.45.0 includes the following runtime dependencies:

Package	Constraint	Resolved
miniflare	workspace:*	3.20240329.1
workerd	1.20240329.0	1.20240329.0
workerd --version	1.20240329.0	2024-03-29

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

[codecov]

Codecov Report

Attention: Patch coverage is 69.29134% with 39 lines in your changes are missing coverage. Please review.

Project coverage is 72.18%. Comparing base (b531b59) to head (d342bd6).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #5215      +/-   ##
==========================================
+ Coverage   72.12%   72.18%   +0.06%     
==========================================
  Files         331      331              
  Lines       17123    17175      +52     
  Branches     4371     4386      +15     
==========================================
+ Hits        12350    12398      +48     
- Misses       4773     4777       +4     

Files	Coverage Δ
packages/wrangler/src/api/dev.ts	83.33% <ø> (ø)
...es/wrangler/src/api/integrations/platform/index.ts	16.66% <ø> (ø)
...wrangler/src/api/startDevWorker/ProxyController.ts	61.97% <100.00%> (+1.40%)	⬆️
packages/wrangler/src/api/startDevWorker/events.ts	15.38% <ø> (ø)
packages/wrangler/src/config/index.ts	88.00% <100.00%> (ø)
packages/wrangler/src/config/validation.ts	89.89% <100.00%> (+0.03%)	⬆️
packages/wrangler/src/deploy/deploy.ts	93.31% <ø> (ø)
...wrangler/src/deployment-bundle/apply-middleware.ts	100.00% <ø> (ø)
packages/wrangler/src/deployment-bundle/bundle.ts	87.50% <ø> (-1.03%)	⬇️
...src/deployment-bundle/create-worker-upload-form.ts	90.32% <100.00%> (+0.12%)	⬆️
... and 9 more

... and 5 files with indirect coverage changes

[GregBrimble]

Eagle has landed 🦅

Just need to publish to npm, and then we should be good to go. Looks like there was a problem with that latest run though: https://github.com/cloudflare/workerd/actions/runs/8438068332

[RamIdeas]

Are we going to remove this file before merging?

[GregBrimble]

Thanks for the reminder. Yes, I'll do that now.

[GregBrimble]

Okay, once these pass, I'm merging and will follow up with another PR to bump to the latest workerd version 🚀