IMPOSM3_SINGLE_DIFF undocumented and may not shutdown properly.

[AdamGlass]

Context

Code contains code that checks environment variable IMPOSM3_SINGLE_DIFF. If present, the automatic 'run' style diff import mechanism returns after doing a single update. This functionality is undocumented. Further, the code 'returns' rather than invoking the shutdown() path which does flush/close which may be a bug.

Expected Behavior

IMPOSM3_SINGLE_DIFF documented. Code correctly shuts down after a single diff is processed.

Actual Behavior

IMPOSM3_SINGLE_DIFF undocumented. Code appears to not correctly shut down.

Possible Fix

Change environment variable to command line switch, providing a middle ground between 'diff' and 'run'. Fix lack of shutdown.

Steps to Reproduce

Code inspection

Context

Use automated imposm3 diff application but in a more scriptable way e.g 'it exits when there is nothing to do' than having to sighup the app after X delay.

Your Environment

• Version used:
• Environment name and version (e.g. PostgreSQL x.y.z with PostGIS a.b.c):
• Server type and version:
• Operating System and version:

[olt]

It's not documented because it is for testing/debugging only. The caches are closed via defer, so I don't think there is a bug in this function. So, I'm closing this. Please create a new issue if you want to extend the run command to do more than it does now.