[IT-4485] Add endpoint to emit current balances as CSV

[ConsoleCatzirl]

Add a new API endpoint /balances to output a CSV of GL account
balances appropriate for sending to FloQast.

During the first week of the month, process the balance for the previous
month, otherwise process the month-to-date balance.

The pre-existing endpoints used the Program segment of the chart of
accounts, but the new endpoint uses the GL segment of the chart of
accounts. Refactor fetching the chart of accounts to support arbitrary
segments.

Depends on #52

[coveralls]

coverage: 90.215% (-4.9%) from 95.076%
when pulling 8c36847 on ConsoleCatzirl:balances
into 0b660f4 on Sage-Bionetworks-IT:master.

[brucehoff]

LGTM

[brucehoff]

Very nice updates to documentation.
Please add unit tests for _balance_dates()

[zaro0508]

The description below seems to indicate that the default for these params is true? Why not just make it so that any value other than a case-insensitive true is considered false?

[ConsoleCatzirl]

The goal is for them to enable optional behavior, so not providing a param would be considered disabled, and setting any value except for explicit False values would be considered enabled. Also, this way the empty string is True, so just having ?show_other_code is enough to enable the behavior, instead of needing ?show_other_code=true.

[dpulls]

🎉 All dependencies have been resolved !

[Copilot]

Pull Request Overview

This PR adds a new /balances endpoint that outputs CSV data of GL account balances, designed for FloQast integration. The endpoint dynamically calculates the target period (previous month during the first week, or month-to-date otherwise) and uses the GL segment of the chart of accounts instead of the Program segment used by existing endpoints.

Key changes:

• Added /balances API endpoint with CSV output format
• Refactored chart of accounts fetching to support arbitrary segments (Program vs GL)
• Implemented dynamic period calculation based on current date
• Added comprehensive test coverage for new functionality

Reviewed Changes

Copilot reviewed 9 out of 12 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
tests/unit/test_handler.py	Extensive test additions for new balances functionality, period calculations, and updated mocking
template.yaml	Added new API route, updated parameter names, and enhanced S3/KMS permissions
mip_api/util.py	Added period calculation logic and improved parameter handling functions
mip_api/upstream.py	Refactored to support arbitrary chart segments and added trial balance API calls
mip_api/s3.py	Extracted caching logic into reusable functions with improved error handling
mip_api/chart.py	Split chart retrieval into Program and GL variants, updated function signatures
mip_api/balances.py	New module for balance processing and CSV formatting
mip_api/init.py	Updated main handler to support new endpoint and refactored parameter handling
README.md	Updated documentation to reflect new endpoint and parameter changes

Comments suppressed due to low confidence (1)

[brucehoff]

Thank you for addressing my requests.

[zaro0508]

This PR is a big change and difficult to review because the refactor (in PR #52) is included. Please help out reviewers by rebasing onto master and push up a new commit so that the files diffs only show the difference for this specific change.

[zaro0508]

LGTM, but why does the CI run the coverall check twice?

[ConsoleCatzirl]

that's an excellent question, that's kinda weird behavior. the website also sporadically fails to load for me, so I think they're having some sort of extended partial outage. this is one more way that coveralls has been kinda unreliable, and tbh I'm starting to regret not choosing CodeCov for code coverage.