Support service bindings from Pages projects to workers in a single workerd instance

[penalosa]

Fixes #5918

As of #7251, Wrangler has supported configuring multiple Workers to run in the same workerd instance (with service bindings between them) using multiple -c flags. However, this didn't work for Pages.

This PR adds support for Pages, using the same API as for regular Workers: wrangler pages dev -c wrangler.toml ../other-worker/wrangler.toml. However, a slight difference with Pages (compared to regular Workers) is that you can't customise the location of the Pages config file. As such, the first -c argument must point to the config file for the Pages project, and must be located in the project root. We could've omitted this entirely, but it felt like it would be more confusing to implicitly read a config file that wasn't mentioned—open to dissenting opinions here!

This PR also shifts wrangler pages dev to use startDev() directly rather than going through unstable_dev(), opening the door to removing unstable_dev() entirely in the future.

---

• Tests
  • TODO (before merge)
  • Tests included
  • Tests not necessary because:
• E2E Tests CI Job required? (Use "e2e" label or ask maintainer to run separately)
  • I don't know
  • Required
  • Not required because:
• Public documentation
  • TODO (before merge)
  • Cloudflare docs PR(s): Document improved Pages multiworker experience cloudflare-docs#19175
  • Documentation not necessary because:

[changeset-bot]

🦋 Changeset detected

Latest commit: a4fa6bb

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

This PR includes changesets to release 2 packages

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

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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/12754855934/npm-package-wrangler-7715

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

npm install --save-dev https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/prs/7715/npm-package-wrangler-7715

Or you can use npx with this latest build directly:

npx https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/12754855934/npm-package-wrangler-7715 dev path/to/script.js

Additional artifacts:

cloudflare-workers-bindings-extension:

wget https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/12754855934/npm-package-cloudflare-workers-bindings-extension-7715 -O ./cloudflare-workers-bindings-extension.0.0.0-vd1a1f78d3.vsix && code --install-extension ./cloudflare-workers-bindings-extension.0.0.0-vd1a1f78d3.vsix

create-cloudflare:

npx https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/12754855934/npm-package-create-cloudflare-7715 --no-auto-update

@cloudflare/kv-asset-handler:

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/12754855934/npm-package-cloudflare-kv-asset-handler-7715

miniflare:

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/12754855934/npm-package-miniflare-7715

@cloudflare/pages-shared:

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/12754855934/npm-package-cloudflare-pages-shared-7715

@cloudflare/unenv-preset:

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/12754855934/npm-package-cloudflare-unenv-preset-7715

@cloudflare/vitest-pool-workers:

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/12754855934/npm-package-cloudflare-vitest-pool-workers-7715

@cloudflare/workers-editor-shared:

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/12754855934/npm-package-cloudflare-workers-editor-shared-7715

@cloudflare/workers-shared:

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/12754855934/npm-package-cloudflare-workers-shared-7715

@cloudflare/workflows-shared:

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/12754855934/npm-package-cloudflare-workflows-shared-7715

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

---

wrangler@3.101.0 includes the following runtime dependencies:

Package	Constraint	Resolved
miniflare	workspace:*	3.20241230.1
workerd	1.20241230.0	1.20241230.0
workerd --version	1.20241230.0	2024-12-30

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

[emily-shen]

can we error helpfully if someone tries to run wrangler dev and one of the provided config files is a pages config?

otherwise very excited about pages going through start_dev!

[penalosa]

can we error helpfully if someone tries to run wrangler dev and one of the provided config files is a pages config?

Added!

[emily-shen]

is there any risk to moving pages dev off unstable_dev? as far as i can tell its just a wrapper around startDev but not sure if there's some context I'm missing around why it's been unstable_dev until now.

[penalosa]

unstable_dev used to be a different code path, and was refactored to be startDev() based when --x-dev-env was stabilised. As it stands today, unstable_dev is just a wrapper around startDev