heap-snapshot-sanitizer

heap-snapshot-sanitizer

Stream transform implementation to sanitize heap snapshot. This is to redact sensitive data in the heap snapshots. All strings which are not name of nodes or edges are obfuscated.

why is it needed?

Heap-snapshots are helpful to diagnose memory leaks. One reason they are discouraged in production is that they can contain sensitive data like PII. Obfuscating strings in the heap-snapshot tries to remediate this.

sample usage

  ...
  const Sanitizer = require('heap-sanpshot-santizer');
  ...

  const session = new inspector.Session();
  const fstrm = fs.createWriteStream(filename);
  const sanitizer = new Sanitizer(/*options*/);
  
  session.connect();

  sanitizer.pipe(fstrm);
  fstrm.on('error', (e) => {
    // console.error(e);
  });
  sanitizer.on('error', (e) => {
    // console.error(e);
  });
  sanitizer.on('end', function() {
    sanitizer.unpipe();
    // fstrm.end(); // unpipe should end the filestream
  });
  session.on('HeapProfiler.addHeapSnapshotChunk', (m) => {
    sanitizer.write(m.params.chunk);
    sanitizer.resume();
  });

  session.post('HeapProfiler.takeHeapSnapshot', null, (err, r) => {
    // console.log('Runtime.takeHeapSnapshot done:', err, r);
    session.disconnect();
    sanitizer.end();
  });
  ...

options

• useWorkerThread: {Boolean} Default is false. The chunk is processed in the worker thread. Node.js clones the chunk while passing it over to the worker thread.