Add hook/event after action was dispatched. about alt HOT 5 CLOSED

This is a good point. One pattern that I've adopted is to have a store that waits for every store, I then register a listener on that store and do snapshots there.

class SnapshotStore {
  constructor() {
    this.bindActions(whateverActions)
  }

  onAction() {
    this.waitFor(['Store1', 'Store2', 'Store3', 'Store4'])
  }
}

var snapshotStore = alt.createStore(SnapshotStore)

snapshotStore.listen(() => alt.takeSnapshot())

Funny you mention this, I have some code sitting in a local branch that does something like this. Here's the proposed change which would register a listener on the alt instance for those actions called:

alt.addActionListener(whateverActions.action, () => {
  alt.takeSnapshot()
})

from alt.

I've seen that branch listen-to-actions. But that's not a solution, because it uses internally dispatcher.register(...) and this doesn't guarantee calling order of listeners - such listener is just one more between others.

You solution with SnapshotStore looks interesting, but bug-prone - I have to remember to include every new store there.

For now, I'm using something like this:

class Flux extends Alt {

    constructor() {
        super();
        this.dispatcher.dispatch = _.wrap(this.dispatcher.dispatch, (dispatch, payload) => {
            dispatch.call(this.dispatcher, payload);
            this.onAction(payload);
        });

        this.storage = new Storage('state');
    }

    onAction(payload) {
        var state = this.takeSnapshot();
        this.storage.writeRaw(state);
    }
}

But this feels somewhat hacky, henсe my proposal. I guess it could be usefull to have official public API for this.

from alt.

Ah, I see what you're looking for. I also wish I had the same thing, essentially a "done" handler for when all dispatches have been completed.

This needs to be provided by flux's dispatcher.

For now your workaround, although hacky, is fine.

from alt.

A similar discussion: facebookarchive/flux#138 (comment)

from alt.

@irium

I went ahead and added a helper function for the SnapshotStore discussed above. You mentioned you didn't want to keep track of including every store in there so I made sure it's automatically done.

The commit is here: c104fb7

Usage is:

var makeFinalStore = require('alt/utils/makeFinalStore');
var FinalStore = makeFinalStore(yourAltInstance)

FinalStore.listen(function () {
  console.log('All dispatches have been completed')
})

from alt.