Type issue in "beforeSendSpan"

[nikolovlazar]

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/node

SDK Version

9.27.0

Framework Version

No response

Link to Sentry event

No response

Reproduction Example/SDK Setup

I used the beforeSendSpan to intentionally drop a certain span, but once I added return null TypeScript warned me that the type of my callback doesn't match the expected type the SDK has defined. The docs in the preview say:

Returning null will cause this span to be dropped.

That's exactly what I wanted to achieve, but I'll have to mute typescript on that line. Is this the intended behavior? If we are allowed to return null to intentionally drop spans, then the SDK should define the expected type as (span: SpanJSON): SpanJSON | null instead.

Steps to Reproduce

Add return null in beforeSendSpan

Expected Result

No TypeScript error should appear

Actual Result

Getting a type mismatch

[nikolovlazar]

okay so I realized there's a log saying:

[Sentry] Returning null from beforeSendSpan is disallowed. To drop certain spans, configure the respective integrations directly.

But, the built-in postgresIntegration does not receive any configuration options:

How can I correctly ignore a span that looks like this?
{ op: 'db', description: 'pg-pool.connect' }

[Lms24]

There are two issues here:

Returning null will cause this span to be dropped.

can you link me to the page in docs where this is written? We need to adjust this. just did this for one place in docs (getsentry/sentry-docs#13906)

beforeSendSpan cannot drop spans at all anymore (we can thank span metrics extrapolation for that fwiw).

How can I correctly ignore a span that looks like this?
{ op: 'db', description: 'pg-pool.connect' }

I don't think you can do this right now but we already discussed that we need to establish more ignore* options in the respective integrations. For now, we you can hack around dropping spans in beforeSendTransaction but long-time, this will go away as well.

[nikolovlazar]

@Lms24 I mean to say the in-code docs, not docs.sentry.io.

[Lms24]

Thanks! opened #16535 to fix the JSDoc