Nginx: No span created when request fails before proxy phase.

[tiithansen]

Steps to reproduce When sending a request with too large header (larger than 8kb). Then nginx rejects/responds with status 400 before any spans are created.

What is the expected behavior? This module should create a span with error status. If possible it should contains cause/exception what happened.

What is the actual behavior? No traces and spans are generated.

Additional context This might not be possible if rejection is done before any modules are executed. But it could be possible to catch in log phase. But it might be tricky to detect cause.