BulkImports: Add custom ErrorTracker to log to the imports.log as well

Everyone can contribute. Help move this issue forward while earning points, leveling up and collecting rewards.

• Close this issue

Proposal

Currently BulkImports is using Gitlab::ErrorTracker to track exceptions. This is great, but it only logs to the exceptions.log file. Since most of the import process is logged within the imports.log, I propose to create a Gitlab::Import::ErrorTracker that log to both exceptions.log and imports.log. This will make debugging and following a import process easier.