Fix logging configuration not propagating to child parser processes

[Copilot]

Logging configuration in cli.py only applied to the main process. Child processes spawned via multiprocessing.Process inherited only the NullHandler, suppressing all warnings and errors from parsing operations.

Changes

• Added _configure_logging(log_level, log_file=None) helper - Configures logging handlers in any process with the same formatter and file output as the parent

• Updated cli_parse() signature - Accepts log_level and log_file parameters, calls _configure_logging() on entry to set up logging in child process

• Modified Process creation - Captures and passes logger.level and opts.log_file from parent to child processes

Example

Before this change, DNS warnings in child processes were invisible:

# cli_parse runs in child process - warnings silently lost
logger.warning(f"get_reverse_dns({ip_address}) exception: {e}")

After this change, all logging configuration propagates:

$ parsedmarc --warnings sample.xml
WARNING:utils.py:208:get_reverse_dns(12.20.127.122) exception: All nameservers failed...

The fix uses exact type checking (type(h) is logging.StreamHandler) to distinguish StreamHandler from FileHandler subclass, and catches specific file I/O exceptions rather than bare Exception.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• 1.0.0.1
  • Triggering command: REDACTED, pid is -1 (packet block)
• 1.1.1.1
  • Triggering command: REDACTED, pid is -1 (packet block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Original prompt

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This section details on the original issue you should resolve

<issue_title>Logging configuration from cli.py not propagated to child parser processes</issue_title>
<issue_description>High-Level:
The log configuration in cli.py only applies to the main script, not to the child processes it creates for parsing.
The log messages from cli.py work because they are executed in the parent process before the child processes are finished.

Break Down:

1. The Process starts, executing the cli_parse function.

2. cli_parse calls parse_report_file (from __init__.py).

3. parse_report_file eventually calls get_ip_address_info (from utils.py).

4. get_ip_address_info calls your function, get_reverse_dns (from utils.py).

5. When a dns.exception.DNSException occurs inside get_reverse_dns, it calls logger.warning(...).

6. This logger.warning is handled by the NullHandler because the FileHandler was only configured in the parent process.
   </issue_description>

<agent_instructions>This is an old issue. I don't know if it is still a problem. Check and see if the problem still exists, and if so, open a PR to fix it.</agent_instructions>

Comments on the Issue (you are @copilot in this section)

• Fixes Logging configuration from cli.py not propagated to child parser processes #605

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