fix(miniflare): allow tcp connection when a outboundService is configured

[edmundhung]

Fixes n/a.

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• Tests
  • Tests included/updated
  • Automated tests not possible - manual testing has been completed as follows:
  • Additional testing not necessary because:
• Public documentation
  • Cloudflare docs PR(s):
  • Documentation not necessary because: bugfix

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[changeset-bot]

🦋 Changeset detected

Latest commit: f935c02

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

This PR includes changesets to release 5 packages

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

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[workers-devprod]

Codeowners approval required for this PR:

• ✅ @cloudflare/wrangler

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[github-actions]

✅ All changesets look good

[ask-bonk]

I'm Bonk, and I've done a quick review of your PR.

This PR adds the connect_pass_through compatibility flag to the custom fetch service worker used for outboundService, so that TCP connect events pass through instead of failing when there's no connect handler.

1. Missing the same fix for SCRIPT_CUSTOM_NODE_SERVICE (medium severity): The node-style custom service handler (line ~473) has the identical structure -- a service worker script with only a fetch listener, also constructed in maybeGetCustomServiceService. It would have the same TCP passthrough failure if used as an outbound service. It should also receive the connect_pass_through and experimental compatibility flags. Specifically, at line 474, the block:

serviceWorkerScript: SCRIPT_CUSTOM_NODE_SERVICE,
compatibilityDate: "2022-09-01",
bindings: [

should become:

serviceWorkerScript: SCRIPT_CUSTOM_NODE_SERVICE,
compatibilityDate: "2022-09-01",
compatibilityFlags: ["connect_pass_through", "experimental"],
bindings: [

[ask-bonk]

Review posted successfully on PR #13999.

Here's a summary of the review:

The fix itself is correct -- adding connect_pass_through and experimental compatibility flags to the custom fetch service worker allows TCP connections (via cloudflare:sockets) to pass through when an outboundService is configured. The test is well-structured and covers both fetch interception and TCP passthrough in the same scenario.

One actionable issue found: The SCRIPT_CUSTOM_NODE_SERVICE branch in the same maybeGetCustomServiceService function (line ~473) has an identical structure -- a service worker with only a fetch event listener -- and would suffer from the same TCP failure. It should also receive the connect_pass_through flag for consistency.

github run

[devin-ai-integration]

Devin Review found 1 potential issue.

View 2 additional findings in Devin Review.

[pkg-pr-new]

create-cloudflare

npm i https://pkg.pr.new/create-cloudflare@13999

@cloudflare/kv-asset-handler

npm i https://pkg.pr.new/@cloudflare/kv-asset-handler@13999

miniflare

npm i https://pkg.pr.new/miniflare@13999

@cloudflare/pages-shared

npm i https://pkg.pr.new/@cloudflare/pages-shared@13999

@cloudflare/unenv-preset

npm i https://pkg.pr.new/@cloudflare/unenv-preset@13999

@cloudflare/vite-plugin

npm i https://pkg.pr.new/@cloudflare/vite-plugin@13999

@cloudflare/vitest-pool-workers

npm i https://pkg.pr.new/@cloudflare/vitest-pool-workers@13999

@cloudflare/workers-editor-shared

npm i https://pkg.pr.new/@cloudflare/workers-editor-shared@13999

@cloudflare/workers-utils

npm i https://pkg.pr.new/@cloudflare/workers-utils@13999

wrangler

npm i https://pkg.pr.new/wrangler@13999

commit: f935c02

[dario-piotrowicz]

LGTM 🙂

[workers-devprod]

Codeowners reviews satisfied