node addJson.js command path/to/file.json

addJson.js

const { spawn } = require('child_process');
const { readFile } = require('fs');
const [app, ...args] = process.argv.slice(2, -1);
const pathToJson = process.argv.slice(-1)[0];

readFile(pathToJson, 'utf8', (err, content) => {
  if (err) {
    console.error(err);
  } else {
    const command = spawn(app, [...args, content]);
    command.stdout.on('data', data => {
      console.log('stdout: ' + data.toString());
    });
    
    command.stderr.on('data', data => {
      console.log('stderr: ' + data.toString());
    });
    
    command.on('exit', code => {
      console.log('child process exited with code ' + code.toString());
    });
  }
});