data-validation-gini 0.1.5

Data Validation Gini (DVG) CLI for row count and row/column comparison with HTML reports

Data Validation Gini (DVG)

Data Validation Gini is a lightweight Python CLI for validating source and target datasets and generating a rich HTML reconciliation report.

The repository also includes a CSV data mutation utility (data_corruptor.py) to create controlled mismatches for validation testing.

What This Project Does

• Compares source vs target files using row-level and cell-level checks.
• Supports CSV and Excel (.xlsx, .xlsm, .xltx) inputs.
• Supports single-sheet and multi-sheet validation (via sheet mapping).
• Produces a styled, filterable HTML report with KPI summary cards.
• Includes repeatable batch scripts for common mutation and validation scenarios.

Current Validation Modes

• ROWCOUNT: checks source/target data row counts.
• ROW_COL_VALIDATION: checks headers and row/column values.
• Combined mode: pass both as comma-separated values:
  • ROWCOUNT,ROW_COL_VALIDATION

Key Features in Current Implementation

• Header mismatch detection:
  • header length mismatches
  • header name mismatches
• Row alignment using preferred key columns:
  • employee_id, id, emp_id, record_id, pk
  • falls back to first column if no preferred key exists
• Mismatch classification:
  • CELL
  • SRC_ONLY
  • TGT_ONLY
  • HEADER_LENGTH
  • HEADER_NAME
  • ROWCOUNT
• HTML report KPIs:
  • SRC Count
  • TGT Count
  • PASSED
  • FAILED
  • Pass Rate
  • Failed Rate
  • SRC Only
  • TGT Only
• Per-column filter inputs in mismatch table for quick triage.

Requirements

• Python 3.9+
• Packages:
  • openpyxl
  • pytest (for tests)
  • python-dotenv

Install dependencies:

pip install -r requirements.txt

Quick Start (Windows Batch Flow)

From project root:

001_env.bat
002_activate.bat
003_setup.bat

Run all mutation scenarios:

004_run.bat

Run a DVG validation and generate HTML:

dvg.bat

Run sheet mapping validation (Excel to Excel):

006_run_sheet_mapping.bat

Deactivate venv:

008_deactivate.bat

CLI Usage

DVG Validator

python dvg.py \
  --file-type EXCEL \
  --src-path inputs/employees.csv \
  --tgt-path outputs/employees.csv \
  --validation-type ROWCOUNT,ROW_COL_VALIDATION \
  --html-output output/report_<datetime>.html

Optional arguments:

• --src-sheet <sheet_name>
• --tgt-sheet <sheet_name>
• --sheet-mapping "SRC1:TGT1,SRC2:TGT2"
• --chunk-size <positive_int> (default: 1000)

Notes:

• --sheet-mapping is supported only for Excel file pairs.
• --file-type currently accepts EXCEL (for both CSV and Excel processing paths).
• <datetime> token in --html-output is replaced at runtime with YYYYMMDD_HHMMSS.
• --chunk-size controls the number of data rows read per batch for CSV/XLSX loading.

Large-file tuning tip:

• Start with --chunk-size 1000 (default), then increase to 2000 or 5000 for faster reads if memory allows.
• In dvg.bat, set CHUNK_SIZE in the config block to tune batch size without changing CLI commands.

Installed CLI Entry Point

If installed as a package, you can run:

dvg --file-type EXCEL --src-path ... --tgt-path ... --validation-type ROWCOUNT

Data Mutation Utility (data_corruptor.py)

Use this utility to generate controlled data drift before validation.

Example:

python data_corruptor.py \
  --input inputs/employees.csv \
  --output outputs/employees_typos.csv \
  --column email \
  --percentage 1.0 \
  --type typo

Supported mutation types:

• nullify
  • Replaces selected values with blank strings.
  • Purpose: validate missing-value detection.
• case_swap
  • Swaps letter casing in selected values.
  • Purpose: validate case sensitivity behavior.
• numeric_shift
  • Adds/subtracts a numeric offset (--value).
  • Purpose: validate precision and tolerance checks.
• date_shift
  • Shifts date/datetime values by day count (--value).
  • Supported formats: YYYY-MM-DD, YYYY-MM-DD HH:MM:SS.
  • Purpose: validate temporal drift handling.
• typo
  • Randomly replaces one character in selected strings.
  • Purpose: validate strict text/hash mismatch detection.

Sample Scenario Scripts

• run_case_swap.bat
• run_date_shift.bat
• run_nullify.bat
• run_numeric_shift.bat
• run_typo.bat

Each script mutates inputs/employees.csv into a corresponding file under outputs/.

Reports

Generated reports are written under output/ and include:

• high-level pass/fail status
• validation metadata (source, target, validation type, timestamp)
• KPI cards
• detailed mismatch table with filters

Tests

Run tests with:

pytest

Project Structure (High Level)

• dvg.py - validation CLI
• dvg_report.py - HTML report generation
• data_corruptor.py - mutation utility
• inputs/ - baseline sample datasets
• outputs/ - mutated sample datasets
• output/ - generated report files
• tests/ - unit tests

License

MIT