remove empty or null keys from JSON file; print to stdout or to file with `-o output.json`; to beautify output JSON add the `-f` flag

json_remove_null_keys.js

#!/usr/bin/env node

const fs = require('fs');

// Function to remove null keys from an object
function removeEmpty(obj) {
  Object.keys(obj).forEach(function(key) {
    if (obj[key] && typeof obj[key] === 'object') {
      removeEmpty(obj[key]);
    } else if (obj[key] === '' || obj[key] === null) {
      delete obj[key];
    }
  });
  return obj;
}

// Read the input file path from command line arguments
const inputFile = process.argv[2]; // Corrected this line

if (!inputFile) {
  console.error('Usage: node script.js <input-file> [-o output.json]');
  process.exit(1);
}

// Read the JSON data from the input file
try {
  const jsonData = JSON.parse(fs.readFileSync(inputFile, 'utf8'));
  const cleanedData = removeEmpty(jsonData);

  // Check if the -o flag is provided for output file
  const outputFileIndex = process.argv.indexOf('-o');
  if (outputFileIndex !== -1 && process.argv[outputFileIndex + 1]) {
    const outputFileName = process.argv[outputFileIndex + 1];
    fs.writeFileSync(outputFileName, JSON.stringify(cleanedData, null, process.argv.includes('-f') ? 2 : 0));
    console.log(`Result written to ${outputFileName}`);
  } else {
    console.log(JSON.stringify(cleanedData, null, process.argv.includes('-f') ? 2 : 0));
  }
} catch (error) {
  console.error('Error reading or processing the input file:', error.message);
}