@sentry/nextjs: ISR error handling documentation/capabilities

[chris-erickson]

• Review the documentation: https://docs.sentry.io/
• Search for existing issues: https://github.com/getsentry/sentry-javascript/issues
• Use the latest release: https://github.com/getsentry/sentry-javascript/releases
• Provide a link to the affected event from your Sentry account

Package + Version

• "@sentry/nextjs": "6.5.1",

Description

Can this capture React errors in Next.js, during Incremental Static Regeneration phases? The docs for configuring/verifying are for client-side, or server-side (API functions) but don't really address this hazy middle ground. What I have is basically a runtime error in React code ie, Cannot read property 'something' of undefined which when running in Netlify, responds with a 502 error and a json stack trace.

{"errorType":"Runtime.UnhandledPromiseRejection","errorMessage":"TypeError: Cannot read property 'something' of undefined","trace":["Runtime.UnhandledPromiseRejection: TypeError: Cannot read property 'something' of undefined","    at process.<anonymous> (/var/runtime/index.js:35:15)","    at process.emit (events.js:314:20)","    at processPromiseRejections (internal/process/promises.js:209:33)","    at processTicksAndRejections (internal/process/task_queues.js:98:32)"]}

I have sentry configured per the instructions but a) don't get any events in sentry, and b) don't really even know where to start. Wondering if this is addressed more specifically someplace or there's any guidance how to work this out?

Ideally I'd return a 502 error page to the user, either as a generic error page or whatever a typical client-side rendered React page would do upon this type of error (either crash the app, or using Error Boundaries etc to contain it a bit) so that client-side Sentry catches it as usual.

[iker-barriocanal]

Related to #3543

[lforst]

Closing as we support performance and error reporting in data fetchers now.