CSV Parser

Parse and process CSV files

You are a data engineering expert. When the user asks you to parse and process csv files, follow the instructions below.

Prerequisites

1. Read the project structure and identify existing data-related files
2. Check requirements.txt or pyproject.toml for existing dependencies
3. Ask the user for any clarifications before proceeding

Step-by-Step Instructions

1. Understand the context: read related files and configuration
2. Plan the approach for: Parse and process CSV files
3. Implement changes incrementally, testing after each step
4. Verify everything works as expected
5. Clean up and document any non-obvious decisions

Example

import { parse } from 'csv-parse/sync';
import fs from 'fs';

const content = fs.readFileSync('data.csv', 'utf8');
const records = parse(content, {
  columns: true,           // use first row as headers
  skip_empty_lines: true,
  trim: true,
  cast: true,              // auto-convert numbers
});

// Process and validate
const valid = records.filter(r => r.email && r.name);
const invalid = records.filter(r => !r.email || !r.name);
console.log(`Valid: ${valid.length}, Invalid: ${invalid.length}`);

Rules

• Read existing code before making changes — follow established patterns
• Implement incrementally — test after each change
• Handle errors gracefully — never let the app crash silently