spreadsheet-source-validated

Validated Python Execution for Spreadsheet Tasks

Pre-Execution Data Validation

CRITICAL: Before attempting any spreadsheet operations, validate that your source data is accessible and complete.

Step 1: Verify Data Source Availability

import os
import sys
from pathlib import Path

def validate_source_data(source_paths):
    """Validate all required data sources before processing."""
    missing = []
    inaccessible = []
    
    for path in source_paths:
        p = Path(path)
        if not p.exists():
            missing.append(str(path))
        elif not os.access(path, os.R_OK):
            inaccessible.append(str(path))
    
    if missing:
        print(f"ERROR: Missing data sources: {', '.join(missing)}", file=sys.stderr)
        return False
    if inaccessible:
        print(f"ERROR: Inaccessible data sources: {', '.join(inaccessible)}", file=sys.stderr)
        return False
    
    print(f"VALIDATED: {len(source_paths)} source(s) available")
    return True

# Usage
sources = ['input.xlsx', 'reference_data.csv']
if not validate_source_data(sources):
    sys.exit(1)

Step 2: Verify Data Integrity

import pandas as pd
from openpyxl import load_workbook

def validate_spreadsheet_integrity(file_path, required_sheets=None, required_columns=None):
    """Check spreadsheet structure before processing."""
    try:
        # Check file is readable
        wb = load_workbook(file_path, read_only=True)
        
        # Verify required sheets exist
        if required_sheets:
            missing_sheets = [s for s in required_sheets if s not in wb.sheetnames]
            if missing_sheets:
                print(f"ERROR: Missing sheets: {missing_sheets}", file=sys.stderr)
                wb.close()
                return False
        
        # Verify required columns (sample first sheet)
        if required_columns:
            ws = wb.active
            headers = [cell.value for cell in ws[1]]
            missing_cols = [c for c in required_columns if c not in headers]
            if missing_cols:
                print(f"ERROR: Missing columns: {missing_cols}", file=sys.stderr)
                wb.close()
                return False
        
        wb.close()
        print(f"VALIDATED: Spreadsheet structure OK")
        return True
        
    except Exception as e:
        print(f"ERROR: Cannot validate spreadsheet: {str(e)}", file=sys.stderr)
        return False