fix(file-based): Switch Excel parser from calamine to openpyxl engine (do not merge)

[devin-ai-integration]

fix(file-based): Switch Excel parser from calamine to openpyxl engine (do not merge)

Requested by: @agarctfi in airbytehq/oncall#10097

Summary

This PR switches the Excel parser engine from calamine to openpyxl to fix crashes when parsing Excel files with invalid date values (e.g., year 20225).

⚠️ CRITICAL DEPENDENCY ISSUE:

• openpyxl is NOT currently a dependency of airbyte-python-cdk
• This PR will break Excel parsing unless openpyxl is added to the file-based extra in pyproject.toml
• See "Dependency Requirements" section below

The Problem:

• The calamine engine (Rust-based via PyO3) panics when encountering date values that result in years outside Python's datetime range (1-9999)
• This causes a pyo3_runtime.PanicException that crashes the entire sync, even after processing millions of records
• Customer reported in airbytehq/oncall#10097

The Solution:

• Switch to openpyxl engine (pure Python) which handles edge cases more gracefully
• Trade-off: openpyxl is slower than calamine, but reliability > speed for production syncs

Change:

• Single line change in excel_parser.py: engine="calamine" → engine="openpyxl"

Dependency Requirements

REQUIRED BEFORE MERGE:
Add openpyxl to the file-based extra in pyproject.toml:

[tool.poetry.extras]
file-based = ["avro", "fastavro", "pyarrow", "unstructured", "pdf2image", "pdfminer.six", "unstructured.pytesseract", "pytesseract", "markdown", "python-calamine", "python-snappy", "openpyxl"]

And add to dependencies section:

openpyxl = { version = "^3.1.0", optional = true }

Alternative Approach:
Instead of a global switch, consider implementing a fallback mechanism:

try:
    return pd.ExcelFile(fp, engine="calamine").parse()
except Exception as e:
    logger.warning(f"Calamine parsing failed, falling back to openpyxl: {e}")
    return pd.ExcelFile(fp, engine="openpyxl").parse()

This would provide the performance benefits of calamine for normal files while gracefully handling edge cases with openpyxl.

Review & Testing Checklist for Human

⚠️ IMPORTANT - This change affects ALL file-based sources that parse Excel files (Google Drive, S3, Azure Blob, GCS, etc.)

• Dependency Addition: Add openpyxl to pyproject.toml as shown above
• Performance Impact: Test with large Excel files (1M+ rows) to verify acceptable performance with openpyxl vs calamine
• Reproduce Original Issue: Test with an Excel file containing invalid date values (year > 9999) to confirm the crash is fixed
• Behavioral Differences: Verify openpyxl handles all Excel features that calamine supported (formulas, formatting, multiple sheets, etc.)
• Regression Testing: Run integration tests for all file-based sources (source-google-drive, source-s3, source-azure-blob-storage, source-gcs) to ensure no regressions
• Consider Configuration: Evaluate whether this should be a configurable option rather than a hard switch (allows rollback if issues arise)
• Consider Fallback: Evaluate implementing calamine→openpyxl fallback instead of global switch

Test Plan

1. Create an Excel file with a date cell containing year 20225 (or use customer's file from oncall issue)
2. Configure source-google-drive to sync this file
3. Verify sync completes successfully without crashing
4. Compare sync performance before/after with large Excel files

Notes

• Lint and type checks passed locally
• Unable to fully reproduce the exact crash scenario locally because Python's datetime module itself cannot handle year 20225
• This is a minimal change (1 line) but has broad impact across all file-based Excel sources
• Marked as "(do not merge)" until dependency issue is resolved and approach is approved
• Session: https://app.devin.ai/sessions/71d8d01ca39f44d3a6486c24a03d071e

[devin-ai-integration]

Original prompt from API User

Comment from @agarctfi: /ai-repro can you also see if switching to openpyxl would fix this?\n\nIMPORTANT: The user will expect a response posted back to the PR. You should post exactly one comment back to the respective issue PR. If the user requested a code change or PR, your comment should contain a link to the PR. Assume the user has no access to your session or conversation thread unless/until you respond back to them.\n\nIssue #10097 by @iherdt-airbyte: Source: Google Drive `Excel format parser crashes`\n\nIssue URL: https://github.com/airbytehq/oncall/issues/10097\n\nPlease use playbook macro: !issue_repro

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[github-actions]

PyTest Results (Fast)

3 813 tests  ±0   3 801 ✅ ±0   6m 34s ⏱️ +6s
    1 suites ±0      12 💤 ±0 
    1 files   ±0       0 ❌ ±0 

Results for commit f4270d1. ± Comparison against base commit 5d9125f.

[github-actions]

PyTest Results (Full)

3 816 tests  ±0   3 804 ✅ ±0   10m 49s ⏱️ +2s
    1 suites ±0      12 💤 ±0 
    1 files   ±0       0 ❌ ±0 

Results for commit f4270d1. ± Comparison against base commit 5d9125f.