SDK must validate envelope size to ensure errors are not silently dropped

[kkmuffme]

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 SDK are you using?

@sentry/browser

SDK Version

10.25.0

Framework Version

No response

Link to Sentry event

No response

Reproduction Example/SDK Setup

No response

Steps to Reproduce

1. Sentry.captureException( new Error( "put a text > 1 MB here" ) );

Expected Result

The SDK should validate that payloads it sends are within the limits https://develop.sentry.dev/sdk/envelopes/#size-limits
If they're too large, truncate them or if that is not possible/still too large, send a generic, short event with minimum possible data to ensure that Sentry customers are at least aware that there are errors happening

Otherwise, it's possible that some errors are never reported, which makes Sentry useless

While it's possible to custom implement this validation (to some extent) via customization or by customizing tunnel/relay, I don't think it makes sense since this is something that all sentry users need

Actual Result

{"detail":"envelope exceeded size limits for type 'event' (https://develop.sentry.dev/sdk/envelopes/#size-limits)"}

Additional Context

Our site was broken for 15% of potential customers, who could not place their order, however we only found out by accident since the events never reached Sentry, resulting in significant loss in revenue

[linear]

JS-1167

[s1gr1d]

Hello and thanks for writing in. This sounds definitely frustrating and you are right, that although this can be manually customized, this should actually be a default. I'm gonna take a look at this this week to fix this.

[kkmuffme]

Thanks!
Ideally in a way to optionally disable this for specific types (e.g. event/transaction/span/log but not for profile/replay), since I've already implemented a tunnel/relay feature now that will convert event data that is too long to an attachment so it's not lost at least (unless of course the SDK would do that)