Output JSON from STDIN Line-By-Line And Pretty Print

json_by_line.js

/*
 * Credit to the Node.js Docs for the line-by-line `ReadStream` example.
 *
 *   https://nodejs.org/api/readline.html#readline_example_read_file_stream_line_by_line
 */

const readline = require('readline');

var stdin = process.stdin;

stdin.resume();
stdin.setEncoding('utf8');

/**
 * Handy function for formatting messages that return JSON in their body.
 *
 * Comment out the full logging if you need this instead.
 */
function formatMessage(message) {
    console.log(`url = ${message.url}`);
    if (message.responseBody) {
        console.log(`response body = \n\n${JSON.stringify(JSON.parse(message.responseBody), null, 2)}`);
    }
}

async function processLineByLine() {
  const rl = readline.createInterface({
    input: stdin,
    crlfDelay: Infinity
  });
  // Note: we use the crlfDelay option to recognize all instances of CR LF
  // ('\r\n') in input.txt as a single line break.

  for await (const line of rl) {
    // Each line in input.txt will be successively available here as `line`.
    const message = JSON.parse(line);
    console.log("\n\n==================\n");
    console.log(JSON.stringify(message, null, 2));
    //formatMessage(message);
  }
}

processLineByLine();