Uh oh!
There was an error while loading. Please reload this page.
Backport #2059: feat(core): support passing parent WritableStream to child workflow via start() - #2070
Merged
Merged
Conversation
…ia start() (#2059) * test(e2e): cover WritableStream passed as start() argument Adds an e2e workflow + test where a parent workflow gets a WritableStream via getWritable(), forwards it through start() to a child workflow, and the child step writes raw bytes to it. Asserts the external reader on the parent's stream observes the exact bytes the child wrote. * fix(core): avoid double-framing when WritableStream is forwarded via start() When a workflow's getWritable() handle is passed across start() to a child workflow, the parent step's reviver wraps it in a serialize transform that pipes into a workflow server stream. Until now, getExternalReducers.WritableStream then installed a second serialize transform on top of that — so every chunk the child step wrote got devalue-framed twice but only deframed once on the reader side, and external consumers saw the inner frame instead of the original bytes. Fix: tag every user-visible writable that's already backed by a workflow server stream with its (runId, name). When the external reducer recognizes those tags during dehydration, it bridges bytes straight from the new child-side server stream to the original server stream instead of piping through the user's writable. That leaves the producer-side serialize transform (installed once by the child's step reviver) as the only framing layer in the chain. * fix(core): forward (runId, name) when a tagged WritableStream crosses start() Replaces the previous in-process bridge with first-class writable forwarding at the descriptor level. When a parent workflow's getWritable() handle is passed as an argument to a child workflow, the dehydrated descriptor now carries the original (runId, name). The child run's step-side reviver opens the writable against the parent's server stream directly and resolves the parent run's encryption key (encrypt-only) via getEncryptionKeyForRun. This removes the architectural limitation that the bridge could only stay alive for the duration of the parent step process — on Vercel that capped forwarding at ~15 minutes regardless of the child run's lifetime, dropping any writes the child made after the parent step process exited. importKey() now accepts a usages parameter, defaulting to ['encrypt', 'decrypt']. The cross-run forwarding path imports with ['encrypt'] only so a compromised child run cannot decrypt any existing data on the parent's stream — only contribute new writes. * test: rename writable-forwarded workflows and cover step-context getWritable() Addresses PR review: - Rename writableForwardedToChildChildWorkflow → writableForwardedChildWorkflow (drops the duplicated 'Child' segment). - Split writableForwardedToChildWorkflow into two variants covered by a test.each: writableForwardedFromWorkflowWorkflow (workflow-context getWritable, the original test) and writableForwardedFromStepWorkflow (step-context getWritable passed directly into start() from the same step that called getWritable()). - Terser changeset description. Signed-off-by: Nathan Rajlich <n@n8.io>
🦋 Changeset detectedLatest commit: 75cdb77 The changes in this PR will be included in the next version bump. This PR includes changesets to release 17 packages
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 |
Contributor
ContributorAuthor
🧪 E2E Test Results❌ Some tests failed Summary
❌ Failed Tests▲ Vercel Production (2 failed)astro (1 failed):
example (1 failed):
🌍 Community Worlds (71 failed)mongodb-dev (1 failed):
redis-dev (1 failed):
turso-dev (1 failed):
turso (68 failed):
Details by Category❌ ▲ Vercel Production
✅ 💻 Local Development
✅ 📦 Local Production
✅ 🐘 Local Postgres
✅ 🪟 Windows
❌ 🌍 Community Worlds
✅ 📋 Other
❌ Some E2E test jobs failed:
Check the workflow run for details. |
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for freeto join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Automated backport of #2059 to
stable(backport job run).AI recommendation: This commit fixes two real bugs in existing functionality that exists on
stable— forwarding a parent'sWritableStream(fromgetWritable()) to a child workflow viastart(). Onstablethis pattern silently drops child writes after the parent step process exits (notably on Vercel after ~15 minutes) and double-frames every chunk so external consumers see the inner devalue frame instead of raw bytes. The affected files (encryption.ts,serialization.ts,step/writable-stream.ts,symbols.ts,99_e2e.ts) all exist onstable, and the change is self-contained without dependencies onmain-only APIs.Merge conflicts were resolved by AI (opencode with
anthropic/claude-opus-4.7). Please review the conflict resolution carefully before merging.