Pull Request

Description

This pull request introduces mock testing for fetch_data and format_forecast functions to enhance test reliability and isolate external dependencies.

fetch_data and fetch_data_using_sql:

• Mock tests validate successful API and SQL query handling.
• Added failure scenarios to ensure robust error handling.

format_to_forecast_sql:

• Mocked data replaces real API calls while maintaining PostgreSQL container functionality.
• Ensures compatibility with controlled input for seamless database interactions.

Fixes #27

How Has This Been Tested?

The following tests have been conducted:

• Mock Testing:
  • Successful mock API/SQL responses were verified for correct DataFrame handling.
  • Failure scenarios ensure empty DataFrames and proper exception handling.
• Integration Testing:
  • PostgreSQL container setup validated through real database interactions.
  • Real database checks preserved for comprehensive coverage.

Steps to reproduce:

1. Run pytest tests/test_fetch_data.py -s.
2. Run pytest tests/test_format_forecast.py -s.

Checklist

• My code follows [OCF's coding style guidelines](https://github.com/openclimatefix/.github/blob/main/coding_style.md).
• I have performed a self-review of my own code.
• I have made corresponding changes to the documentation (if applicable).
• I have added tests that prove my fix is effective or that my feature works.
• I have checked my code and corrected any misspellings.