Fix race conditions in webhook response handling

[TooTallNate]

Fixed a race condition in the streamer where close events could arrive during disk reads, causing premature controller closure. This fixes the flakiness in the webhookWorkflow E2E test on "local" test suites.

What changed?

• Added a pendingClose flag to buffer close events that arrive during disk reading
• Modified the closeListener function to set this flag instead of immediately closing the controller when disk reads are in progress
• Added logic to process any pending close events after disk reads complete

Why make this change?

There was a race condition in the streamer where close events arriving during disk reads would close the controller before all data was enqueued. This could lead to incomplete data streams and potential data loss. This fix ensures that all data is properly processed before the stream is closed.

[changeset-bot]

🦋 Changeset detected

Latest commit: e764695

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

This PR includes changesets to release 14 packages

Name	Type
@workflow/world-local	Patch
@workflow/cli	Patch
@workflow/core	Patch
@workflow/world-postgres	Patch
workflow	Patch
@workflow/world-testing	Patch
@workflow/builders	Patch
@workflow/next	Patch
@workflow/nitro	Patch
@workflow/web-shared	Patch
@workflow/ai	Patch
@workflow/astro	Patch
@workflow/sveltekit	Patch
@workflow/nuxt	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

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Project	Deployment	Review	Updated (UTC)
example-nextjs-workflow-turbopack	Ready	Preview, Comment	Dec 22, 2025 8:22am
example-nextjs-workflow-webpack	Ready	Preview, Comment	Dec 22, 2025 8:22am
example-workflow	Ready	Preview, Comment	Dec 22, 2025 8:22am
workbench-astro-workflow	Ready	Preview, Comment	Dec 22, 2025 8:22am
workbench-express-workflow	Ready	Preview, Comment	Dec 22, 2025 8:22am
workbench-fastify-workflow	Ready	Preview, Comment	Dec 22, 2025 8:22am
workbench-hono-workflow	Ready	Preview, Comment	Dec 22, 2025 8:22am
workbench-nitro-workflow	Ready	Preview, Comment	Dec 22, 2025 8:22am
workbench-nuxt-workflow	Ready	Preview, Comment	Dec 22, 2025 8:22am
workbench-sveltekit-workflow	Ready	Preview, Comment	Dec 22, 2025 8:22am
workbench-vite-workflow	Ready	Preview, Comment	Dec 22, 2025 8:22am
workflow-docs	Ready	Preview, Comment	Dec 22, 2025 8:22am

[github-actions]

🧪 E2E Test Results

❌ Some tests failed

Summary

	Passed	Failed	Skipped	Total
✅ ▲ Vercel Production	286	0	11	297
✅ 💻 Local Development	262	0	8	270
✅ 📦 Local Production	262	0	8	270
✅ 🐘 Local Postgres	262	0	8	270
✅ 🪟 Windows	27	0	0	27
❌ 🌍 Community Worlds	110	10	0	120
Total	1209	10	35	1254

❌ Failed Tests

🌍 Community Worlds (10 failed)

mongodb (1 failed):

• webhookWorkflow

starter (8 failed):

• addTenWorkflow
• addTenWorkflow
• retryAttemptCounterWorkflow
• crossFileErrorWorkflow - stack traces work across imported modules
• hookCleanupTestWorkflow - hook token reuse after workflow completion
• stepFunctionPassingWorkflow - step function references can be passed as arguments (without closure vars)
• stepFunctionWithClosureWorkflow - step function with closure variables passed as argument
• spawnWorkflowFromStepWorkflow - spawning a child workflow using start() inside a step

turso (1 failed):

• webhookWorkflow

Details by Category

✅ ▲ Vercel Production

App	Passed	Failed	Skipped
✅ astro	26	0	1
✅ example	26	0	1
✅ express	26	0	1
✅ fastify	26	0	1
✅ hono	26	0	1
✅ nextjs-turbopack	26	0	1
✅ nextjs-webpack	26	0	1
✅ nitro	26	0	1
✅ nuxt	26	0	1
✅ sveltekit	26	0	1
✅ vite	26	0	1

✅ 💻 Local Development

App	Passed	Failed	Skipped
✅ astro-stable	26	0	1
✅ express-stable	26	0	1
✅ fastify-stable	26	0	1
✅ hono-stable	26	0	1
✅ nextjs-turbopack-stable	27	0	0
✅ nextjs-webpack-stable	27	0	0
✅ nitro-stable	26	0	1
✅ nuxt-stable	26	0	1
✅ sveltekit-stable	26	0	1
✅ vite-stable	26	0	1

✅ 📦 Local Production

App	Passed	Failed	Skipped
✅ astro-stable	26	0	1
✅ express-stable	26	0	1
✅ fastify-stable	26	0	1
✅ hono-stable	26	0	1
✅ nextjs-turbopack-stable	27	0	0
✅ nextjs-webpack-stable	27	0	0
✅ nitro-stable	26	0	1
✅ nuxt-stable	26	0	1
✅ sveltekit-stable	26	0	1
✅ vite-stable	26	0	1

✅ 🐘 Local Postgres

App	Passed	Failed	Skipped
✅ astro-stable	26	0	1
✅ express-stable	26	0	1
✅ fastify-stable	26	0	1
✅ hono-stable	26	0	1
✅ nextjs-turbopack-stable	27	0	0
✅ nextjs-webpack-stable	27	0	0
✅ nitro-stable	26	0	1
✅ nuxt-stable	26	0	1
✅ sveltekit-stable	26	0	1
✅ vite-stable	26	0	1

✅ 🪟 Windows

App	Passed	Failed	Skipped
✅ nextjs-turbopack	27	0	0

❌ 🌍 Community Worlds

App	Passed	Failed	Skipped
✅ mongodb-dev	3	0	0
❌ mongodb	26	1	0
✅ redis-dev	3	0	0
✅ redis	27	0	0
✅ starter-dev	3	0	0
❌ starter	19	8	0
✅ turso-dev	3	0	0
❌ turso	26	1	0

---

📋 View full workflow run

[TooTallNate]

• Fix stream serialization to resolve when user releases lock instead of waiting for stream to close #661
• Fix race conditions in webhook response handling #672 👈 (View in Graphite)
• main

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[Copilot]

Pull request overview

This PR fixes a race condition in the streamer's readFromStream method where close events arriving during disk reads would immediately close the ReadableStream controller before all data was enqueued, potentially causing data loss.

Key changes:

• Added a pendingClose flag to buffer close events that arrive while reading from disk
• Modified closeListener to set the flag instead of closing immediately when disk reads are in progress
• Added logic to process buffered close events after disk reads and buffered event chunks are processed

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
packages/world-local/src/streamer.ts	Implements the race condition fix by buffering close events during disk reads and processing them after disk reading completes
.changeset/webhook-response-body-fix.md	Documents the fix for the changeset

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