feat(tanstackstart-react): Add global sentry exception middlewares

[nicohrubec]

This PR adds sentryGlobalRequestMiddleware and sentryGlobalFunctionMiddleware that capture unhandled errors from all HTTP requests and server function invocations. Users add these as the first entries in the requestMiddleware / functionMiddleware arrays of createStart(). These internal middlewares get marked with a __SENTRY_INTERNAL__, so that they can be easily skipped in the vite plugin to exclude them from middleware auto-instrumentation. Originally we wanted to do this in the server-entry-point, but since there haven't been any updates on this front in months I propose this as an alternative solution for now. This is probably slightly worse UX but in my case better than having nothing in place.

We could also think about auto-injecting this during the build, but maybe not worth the effort since this is a one-time setup step.

Limitations

Tanstack Start has three types of server-side errors that we care about. With these middlewares we can capture 2 of these (route, function exceptions). We cannot capture SSR exceptions like this, because the exceptions are serialized at a deeper layer and newer thrown.

Usage

import { sentryGlobalFunctionMiddleware, sentryGlobalRequestMiddleware } from '@sentry/tanstackstart-react';
import { createStart } from '@tanstack/react-start';

export const startInstance = createStart(() => ({
  requestMiddleware: [sentryGlobalRequestMiddleware, ...otherMiddleware],
  functionMiddleware: [sentryGlobalFunctionMiddleware, ...otherMiddleware],
}));

Tests

• Updated E2E tests to verify server side function/route errors are being captured
• Added an E2E test to document that SSR exceptions are NOT being captured

Closes #18283

[github-actions]

Codecov Results 📊

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[github-actions]

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.

Scenario	Requests/s	% of Baseline	Prev. Requests/s	Change %
GET Baseline	8,523	-	11,206	-24%
GET With Sentry	1,580	19%	1,856	-15%
GET With Sentry (error only)	5,978	70%	7,570	-21%
POST Baseline	1,135	-	1,166	-3%
POST With Sentry	569	50%	572	-1%
POST With Sentry (error only)	1,018	90%	1,025	-1%
MYSQL Baseline	3,246	-	3,984	-19%
MYSQL With Sentry	445	14%	515	-14%
MYSQL With Sentry (error only)	2,608	80%	3,288	-21%

View base workflow run

[nicohrubec]

typescript kept complaining in my sample app that the types of the new sentry middlewares clash with what is expected from tanstack (it was still running fine thought), had to change it to this to fix that

[andreiborza]

LGTM overall! Nice workaround for the time being.

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[github-actions]

size-limit report 📦

Path	Size	% Change	Change
@sentry/browser	25.56 kB	-	-
@sentry/browser - with treeshaking flags	24.08 kB	-	-
@sentry/browser (incl. Tracing)	42.36 kB	-	-
@sentry/browser (incl. Tracing, Profiling)	47.03 kB	-	-
@sentry/browser (incl. Tracing, Replay)	81.18 kB	-	-
@sentry/browser (incl. Tracing, Replay) - with treeshaking flags	70.8 kB	-	-
@sentry/browser (incl. Tracing, Replay with Canvas)	85.87 kB	-	-
@sentry/browser (incl. Tracing, Replay, Feedback)	98.03 kB	-	-
@sentry/browser (incl. Feedback)	42.29 kB	-	-
@sentry/browser (incl. sendFeedback)	30.23 kB	-	-
@sentry/browser (incl. FeedbackAsync)	35.22 kB	-	-
@sentry/browser (incl. Metrics)	26.74 kB	-	-
@sentry/browser (incl. Logs)	26.88 kB	-	-
@sentry/browser (incl. Metrics & Logs)	27.56 kB	-	-
@sentry/react	27.33 kB	-	-
@sentry/react (incl. Tracing)	44.72 kB	-	-
@sentry/vue	30.01 kB	-	-
@sentry/vue (incl. Tracing)	44.22 kB	-	-
@sentry/svelte	25.58 kB	-	-
CDN Bundle	28.11 kB	-	-
CDN Bundle (incl. Tracing)	43.2 kB	-	-
CDN Bundle (incl. Logs, Metrics)	28.95 kB	-	-
CDN Bundle (incl. Tracing, Logs, Metrics)	44.03 kB	-	-
CDN Bundle (incl. Replay, Logs, Metrics)	68.02 kB	-	-
CDN Bundle (incl. Tracing, Replay)	80.07 kB	-	-
CDN Bundle (incl. Tracing, Replay, Logs, Metrics)	80.94 kB	-	-
CDN Bundle (incl. Tracing, Replay, Feedback)	85.5 kB	-	-
CDN Bundle (incl. Tracing, Replay, Feedback, Logs, Metrics)	86.4 kB	-	-
CDN Bundle - uncompressed	82.22 kB	-	-
CDN Bundle (incl. Tracing) - uncompressed	127.93 kB	-	-
CDN Bundle (incl. Logs, Metrics) - uncompressed	85.05 kB	-	-
CDN Bundle (incl. Tracing, Logs, Metrics) - uncompressed	130.76 kB	-	-
CDN Bundle (incl. Replay, Logs, Metrics) - uncompressed	208.71 kB	-	-
CDN Bundle (incl. Tracing, Replay) - uncompressed	244.81 kB	-	-
CDN Bundle (incl. Tracing, Replay, Logs, Metrics) - uncompressed	247.63 kB	-	-
CDN Bundle (incl. Tracing, Replay, Feedback) - uncompressed	257.61 kB	-	-
CDN Bundle (incl. Tracing, Replay, Feedback, Logs, Metrics) - uncompressed	260.42 kB	-	-
@sentry/nextjs (client)	47.07 kB	-	-
@sentry/sveltekit (client)	42.81 kB	-	-
@sentry/node-core	52.15 kB	+0.02%	+9 B 🔺
@sentry/node	166.53 kB	+0.01%	+5 B 🔺
@sentry/node - without tracing	93.95 kB	+0.02%	+12 B 🔺
@sentry/aws-serverless	109.45 kB	+0.01%	+9 B 🔺

View base workflow run