peek into stream

peek-stream.js

const { pipeline: pipelineAsCallback, Transform, Readable } = require('stream');
const { promisify } = require('util');
const pipeline = promisify(pipelineAsCallback);

const debugStream = new Transform({
  objectMode: true,

  transform(chunk, encoding, callback) {
    console.log('chunk');
    console.log(JSON.stringify(chunk, null, 2));
    this.push(chunk); // forward / passthrough
    callback();
  }
 });

await pipeline([
  teamsUsersMappingStream,
  debugStream,
  teamTransformStream,
  teamWriteStream,
]);