Detecting when vector drops a large log line

[sean-brandenburg]

Hey all, I'm working on adding some alerting for certain error conditions in vector. I have a file source writing to an s3 sink and want to detect when vector has dropped a log because the log line is larger than the source buffer.

I've been looking at the following internal_metrics "component_discarded_events_total", "buffer_discarded_events_total" and "events_discarded_total" on both the sink and source, but none of these seem to capture this case (I tested by appending a 16MB log line to the source file which is larger than the default 10MB buffer) and it none of these metrics were present when I checked the internal_metrics.

Wondering if there's another metric that might capture this or if there's some other way to detect when this happens. Thank you!