feat(remix): Server Timing Headers Trace Propagation PoC#18653
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onurtemizkan wants to merge 2 commits intodevelopfrom
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feat(remix): Server Timing Headers Trace Propagation PoC#18653onurtemizkan wants to merge 2 commits intodevelopfrom
onurtemizkan wants to merge 2 commits intodevelopfrom
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Pull request overview
This PR implements a proof-of-concept for propagating Sentry trace context from server to client using the Server-Timing HTTP header and the browser Performance API. This provides an alternative to meta tag-based trace propagation, particularly useful for streaming SSR responses and edge runtimes.
Key changes:
- Added utilities for generating and injecting Server-Timing headers with Sentry trace data
- Implemented client-side parsing of Server-Timing headers via the Performance API
- Updated server instrumentation to capture and propagate trace context via Server-Timing headers
- Added comprehensive E2E test coverage for both Node.js and Cloudflare environments
Reviewed changes
Copilot reviewed 25 out of 27 changed files in this pull request and generated 16 comments.
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| File | Description |
|---|---|
packages/remix/src/server/serverTimingTracePropagation.ts |
New utility module for generating Server-Timing headers with trace context |
packages/remix/src/client/serverTimingTracePropagation.ts |
New client-side utilities for parsing trace data from Server-Timing headers |
packages/remix/src/server/instrumentServer.ts |
Updated server instrumentation to inject Server-Timing headers and refactored trace propagation logic |
packages/remix/src/client/performance.tsx |
Updated pageload span initialization to use Server-Timing trace propagation |
packages/remix/src/server/index.ts |
Exported new Server-Timing utilities for public API |
packages/remix/src/client/index.ts |
Exported new client-side Server-Timing utilities |
packages/remix/src/cloudflare/index.ts |
Exported Server-Timing utilities for Cloudflare runtime |
dev-packages/e2e-tests/test-applications/remix-server-timing/* |
New E2E test application validating Server-Timing trace propagation |
dev-packages/e2e-tests/test-applications/remix-hydrogen/* |
Updated Hydrogen test app to demonstrate Cloudflare support |
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...2e-tests/test-applications/remix-server-timing/tests/server-timing-trace-propagation.test.ts
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node-overhead report 🧳Note: This is a synthetic benchmark with a minimal express app and does not necessarily reflect the real-world performance impact in an application.
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@onurtemizkan sorry for the delay on this! I merged in #18673 to get support for server-timing trace continuation on the client side in the general browser SDK. Could you update the PR to use this instead of the remix-specific approach? The server side looks fine to me, though I'll give this a more proper look once the PR is updated.
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Codecov Results 📊Generated by Codecov Action |
![sentry[bot]](https://avatars.githubusercontent.com/in/12637?s=60&v=4){kind=small}
dev-packages/e2e-tests/test-applications/remix-hydrogen/app/entry.server.tsx
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size-limit report 📦
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Cursor Bugbot has reviewed your changes and found 1 potential issue.
Bugbot Autofix is OFF. To automatically fix reported issues with Cloud Agents, enable Autofix in the Cursor dashboard.
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Unescaped quotes in Server-Timing desc
Medium Severity
generateSentryServerTimingHeader interpolates sentryTrace and baggage into Server-Timing desc="..." without escaping. If either value ever contains " or \ (for example via non-standard baggage values), the header becomes syntactically invalid and may be dropped or parsed incorrectly by proxies/browsers, breaking trace propagation.
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Adds automatic trace propagation from server to client via the Server-Timing HTTP header for Remix applications. The client-side reading of Server-Timing headers via the Performance API was added in #18673.
Adds:
generateSentryServerTimingHeader(span)public utility that generates a Server-Timing header value containing Sentry trace contextgenerateSentryServerTimingHeader()manually and append the value to the response'sServer-Timingheader in entry.server.tsx (see remix-hydrogen e2e test for example)Works on both Node.js and Cloudflare Workers environments.
Closes #18696