Migrate run() pipeline logging from print() to Python logging module

[krrishrastogi05]

Summary

• What changed: Replaced print() statements in the solver execution pipeline (run() method in DataFileClass.py) with Python's logging module.

• Why: The current print() calls work fine for basic debugging, but they don't give us log levels, timestamps, or any way to capture output programmatically. As we move forward, we'll need to track multi-step execution and potentially stream progress to the UI. Python logging gives us all that while keeping the same console output by default.

Related issues

• Issue exists and is linked
• Closes [Task] Migrate run() pipeline logging from print() to Python logging module #159
• Related Refactor: Migrate Solver Execution Logging to Python logging  #107 (solver binary output logging — different scope, this covers pipeline status)

Validation

• Tests added/updated (or not applicable)
• Validation steps documented
• Evidence attached (logs/screenshots/output as relevant)

How to test:

cd API
python app.py
# Run any model case through the UI
# Console output looks the same as before

To see the structured logging with timestamps, add this to app.py:

import logging
logging.basicConfig(level=logging.INFO, format='%(asctime)s - %(name)s - %(levelname)s - %(message)s')

Then output becomes:

2026-03-03 10:30:45 - Classes.Case.DataFileClass - INFO - PREPROCESSING DONE! --- 2.50 seconds --- case1
2026-03-03 10:30:48 - Classes.Case.DataFileClass - INFO - CREATION OF LP FILE DONE! --- 5.30 seconds --- case1

Documentation

• Docs updated in this PR (or not applicable)
• Any setup/workflow changes reflected in repo docs

No doc changes needed — this is a drop-in replacement that doesn't change any external behavior.

Scope check

• No unrelated refactors
• Implemented from a feature branch
• Change is deliverable without upstream OSeMOSYS/MUIO dependency
• Base repo/branch is EAPD-DRB/MUIOGO:main (not upstream)

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