Fix log overflow

[mschwoer]

Limit log file growth

[claude]

Code Review: Fix log overflow

The approach is sound and follows container best practices. Good overall.

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Bug / Gap: misc/nginx_no_ssl.conf not updated

misc/nginx.conf was correctly updated to redirect logs to /dev/stderr and /dev/stdout, but misc/nginx_no_ssl.conf still has the old file paths:

error_log /var/log/nginx/error.log warn;
access_log /var/log/nginx/access.log main;

Deployments using the no-SSL config will continue writing to files that no longer exist as a mounted volume. nginx will either fail to start or silently produce no logs. Needs the same update as nginx.conf.

Minor: format_message defensive branch is untested and has a type inconsistency

In local_disk_space_alert.py line 43:
free_space_gb = issues[0][1] if issues else 'unknown'

The 'unknown' fallback is never exercised by the test suite and gives the variable an inconsistent int|str type. Since format_message is only called when issues is non-empty (see BaseAlert), this branch is dead code. Either remove it and let it fail loudly (preferred), or add a dedicated test.

Nit: LOCAL_DISK_PATH = '/etc/hosts' deserves a clearer comment

The real assumption is that /etc/hosts lives on the same partition as Docker's overlay filesystem, which is almost always true in Docker but not guaranteed (e.g. in Kubernetes /etc/hosts is a tmpfs bind-mount). Using '/' directly would be more robust and self-documenting.

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Observations

• Log budget: ~10 Airflow workers + other services = ~5-6 GB at peak rotation. LocalDiskSpaceAlert now watches exactly this. Nice symmetry.
• LocalDiskSpaceAlert is well structured: follows DiskSpaceAlert pattern, del status_objects idiom is consistent, tests cover threshold boundary and OSError path.
• Webapp cleanup is the right call; containerised apps should log to stdout.
• docker-compose.yaml coverage is complete: airflow services inherit logging from x-airflow-common, standalone services each have explicit entries. No gaps.

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Summary:

• BLOCKING: misc/nginx_no_ssl.conf not updated -- nginx fails on no-SSL deployments
• Non-blocking: Dead 'unknown' branch in format_message; inconsistent int|str type
• Nit: LOCAL_DISK_PATH comment could clarify the partition assumption