[Replay] NextJS tunnel fails to passthrough Replay payloads

[sdacunha]

Is there an existing issue for this?

• I have checked for existing issues https://github.com/getsentry/sentry-javascript/issues
• I have reviewed the documentation https://docs.sentry.io/
• I am using the latest SDK release https://github.com/getsentry/sentry-javascript/releases

How do you use Sentry?

Sentry Saas (sentry.io)

Which package are you using?

@sentry/nextjs

SDK Version

7.26.0

Framework Version

Next 12.2.5

Link to Sentry event

No response

Steps to Reproduce

1. Setup Sentry Replay, for example:
   sentry.client.config.js

new Replay({
     stickySession: true,
 }),

as well as tunneling, for example:

next.config.js

sentry: {
    widenClientFileUpload: true,
    tunnelRoute: '/monitoring-tunnel',
 },

via an API route or via the tunnelRoute option.
4. Load application

Expected Result

The tunnel is able to passthrough Replay payloads

Actual Result

Sentry reports errors (401 due to missing dsn in envelope) for Replay payloads passed through the tunnel {"detail":"bad envelope authentication header","causes":["missing field `dsn` at line 1 column 157"]}

[Lms24]

Hi @sdacunha thanks for writing in! Can you confirm that sending the Replay envelopes works without using the tunnelRoute option?

[Lms24]

Also would you mind sharing the request payload of a replay envelope request?

[sdacunha]

I can confirm that it does work without the tunnel. With the tunnel, this is what the envelope looks like:

{"event_id":"2f57c813f7e84f88bdabd3fc016d47d1","sent_at":"2022-12-15T19:15:39.343Z","sdk":{"name":"sentry.javascript.integration.replay","version":"7.26.0"}}
{"type":"replay_event"}
{"type":"replay_event","timestamp":1671131739.342,"error_ids":[],"trace_ids":["581699d0da574759a727e206c5c16534"],"urls":["https://WEBSITE_URL/"],"replay_id":"2f57c813f7e84f88bdabd3fc016d47d1","segment_id":10,"platform":"javascript","event_id":"2f57c813f7e84f88bdabd3fc016d47d1","environment":"qa","release":"1dd71ec62357d08aabefcbd6ccb0fd14f58df395","sdk":{"integrations":["InboundFilters","FunctionToString","TryCatch","Breadcrumbs","GlobalHandlers","LinkedErrors","Dedupe","HttpContext","BrowserTracing","Replay","RewriteFrames"],"name":"sentry.javascript.integration.replay","version":"7.26.0"},"tags":{"runtime":"browser","sessionSampleRate":1,"errorSampleRate":1,"replayType":"session"},"transaction":"me","fingerprint":["{{ default }}","me"],"sdkProcessingMetadata":{},"request":{"url":"https://WEBSITE_URL/","headers":{"Referer":"https://WEBSITE_URL/","User-Agent":"Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/108.0.0.0 Safari/537.36"}}}
{"type":"replay_recording","length":8145}
{"segment_id":10}
[BINARY RRWEB DATA]

The key thing here is the first line does not contain the DSN in the JSON as the envelope ingestion API likely expects, so the API returns a 401.

Hope this helps - let me know if theres anything else needed to repro this issue!

[lforst]

@sdacunha Thanks for providing us with the info needed! We think we have identified the issue and there is a fix underway: #6562