Update Next.JS SDK Crons to be Opt-in

[gaprl]

Currently, instrumentation for Crons monitors for our Next.JS is automatic. However, in preparations for GA and to enable billing, we should update this behavior to be opt-in instead, in a similar manner to our Celery Beat integration.

Otherwise, customers might face situations where we unintentionally bill them for Crons.

[AbhiPrasad]

Right now this is gated behind a flag automaticVercelMonitors, which defaults to true.

// next.config.js
const nextConfig = {
  sentry: {
    automaticVercelMonitors: false,
  },
};

If we move ahead with making this false by default, maybe we need to introduce another option that controls what routes get instrumented. @lforst your thoughts?

[lforst]

My thoughts:

• If people have monitors and we switch the default, their monitors will miss and create issues - which would be annoying for them.
• Billing situation sucks, however, in Next.js we also turn on performance monitoring by default which seems very analogous to me.

Considering the points above I would contemplate keeping the functionality as-is.

[AbhiPrasad]

@lforst it's not like we turn it on by default - we explicitly add a tracesSampleRate when generating a Sentry.init. Right now that is completely opaque to users.

Since crons is a beta product, I think it's reasonable to turn it off. @gaprl maybe we can add some in product helpers that guide people toward this? (like hey you've upgraded to the most recent Next SDK version, update your config).

[stephanie-anderson]

On December 11th, billing will be turned on