Hot Code Push NodeJS

Question

I\'ve been trying to figure out this \"Hot Code Push\" on Node.js. Basically, my main file (that is run when you type node app.js) consists of some settings, config

Answer 1

Meteor solves this problem by allowing modules to "register" themselves as part of the hot code push process.

They implement this in their reload package:

https://github.com/meteor/meteor/blob/master/packages/reload/reload.js#L105-L109

I've seen that Meteor.reload API used in some plugins on GitHub, but they also use it in the session package:

https://github.com/meteor/meteor/blob/master/packages/session/session.js#L103-L115

if (Meteor._reload) {
  Meteor._reload.onMigrate('session', function () {
    return [true, {keys: Session.keys}];
  });

  (function () {
    var migrationData = Meteor._reload.migrationData('session');
    if (migrationData && migrationData.keys) {
      Session.keys = migrationData.keys;
    }
  })();
}

So basically, when the page/window loads, meteor runs a "migration", and it's up to the package to define the data/methods/etc. that get recomputed when a hot code push is made.

It's also being used by their livedata package (search reload).

Between refreshes they're saving the "state" using window.sessionStorage.