Extend envelope API to allow event-specific attachments

[hongjiaheng]

Doesn't anyone have this need? Attach specific files when sending events. Currently, the SDK only provides a global interface for attaching files:

Is there a way to attach different files for different events? I think the SDK support this, but it hasn't exposed the corresponding interface, because now it only provide one header file called sentry.h, but there are some userfull function define in sentry_envelope.h i cannot use it.

[supervacuus]

Hi @hongjiaheng. While we expose some envelope interfaces in our header, these mainly deal with loading events/transactions from persisted envelopes.

Exposing envelopes in the send path would require opening up either with another
envelope-centered hook or splitting that path and exposing the parts to the public API.

This would allow users to extend the envelope further after we applied scope-related changes (including global attachments) and invoked the before_send() hook. Then, it would make sense to expose further envelope-related interfaces in the public API to allow, for instance, event-specific attachments.

Let's leave this here so users can vote.