Fix noisy error logging for zero-byte connections #285
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Addresses issue emersion#236 where health checks and load balancer probes that connect and immediately disconnect generate unnecessary 'connection reset by peer' error logs. Changes: - Add hasReceivedData field to Conn struct to track data reception - Set flag in readLine() when SMTP data is successfully read - Only log connection errors if data was actually received - Add comprehensive test covering both scenarios This eliminates log spam from health checks while preserving error visibility for legitimate SMTP sessions. Fixes: emersion#236
|
Sending nothing should not cause a connection error, it should cause an immediate |
When clients connect and immediately disconnect without sending data (common for health checks), return io.EOF instead of connection reset error. This prevents noisy error logs for normal health check behavior. - Modified readLine() to detect zero-byte connections and return EOF - Removed hasReceivedData check from error logging - Added tests to verify health checks don't generate error logs - Real connection errors are still properly logged
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Health checks connect and immediately disconnect without sending any data, this creates noisy logs.
This PR fixes it by only logging errors for connections that actually tried to send SMTP commands. Health checks that send nothing are now silent.
What changed:
Includes a test that proves health checks no longer spam the logs.