@ajay7781/csv-to-json-lite/index.js

Zero-dependency CSV to JSON converter (Node + Browser, modern ESM)

// index.js
// Modern CSV to JSON converter (Node + Browser, ESM, Zero Dependencies)

export async function csvToJson(input, options = {}) {
    const {
      headers = true,
      delimiter = ',',
      headerCase = 'none', // none | camel | snake
      trim = true,
      skipEmpty = true,
    } = options;
  
    const csv = typeof input === 'string' ? input : await input.text();
  
    const lines = csv.split(/\r?\n/).filter(line => (skipEmpty ? line.trim() !== '' : true));
    if (lines.length === 0) return [];
  
    const parseLine = (line) => {
      const regex = new RegExp(
        `(\\\"(?:[^\\\"]|\\\"\\\")*\\\"|[^\"${delimiter}]*)(?:${delimiter}|$)`,
        'g'
      );
      return [...line.matchAll(regex)].map((match) => {
        let value = match[1];
        if (value.startsWith('"') && value.endsWith('"')) {
          value = value.slice(1, -1).replace(/""/g, '"');
        }
        return trim ? value.trim() : value;
      }).filter((v, i, arr) => i < arr.length - 1 || v !== ''); // remove trailing empty
    };
  
    const rawHeader = headers ? parseLine(lines.shift()) : null;
  
    const normalizeHeader = (h) => {
      if (headerCase === 'camel') return h.replace(/[-_\s]+(.)?/g, (_, c) => c ? c.toUpperCase() : '');
      if (headerCase === 'snake') return h.toLowerCase().replace(/\W+/g, '_');
      return h;
    };
  
    const header = rawHeader?.map(normalizeHeader);
  
    const result = lines.map((line) => {
      const values = parseLine(line);
      if (!headers) return values;
      return header.reduce((obj, key, i) => {
        obj[key] = values[i] ?? null;
        return obj;
      }, {});
    });
  
    return result;
  }