dispatch can only be invoked once in each logic?

[tylerlong]

Check the code here: https://github.com/tylerlong/hello-async/blob/1d6d7159a4528b1af7a560ad9c8232b7e6c9493e/redux-logic/src/logics.js

I can show the notification, but cannot hide it.

I checked the examples in your repo and I find that dispatch is only invoked once in each logic. And I guess that's the limitation of this middleware.

[tylerlong]

If I create an extra logic and move the second dispatch there, it works like a charm.

https://github.com/tylerlong/hello-async/blob/2f037cd96da276a446822cfc1530113af1cb070d/redux-logic/src/logics.js

So I guess I am right in concluding that you can only invoke dispatch once in each logic.

Do you think this limitation is necessary? Do you think it's a big disadvantage for this library?

[tylerlong]

I tried done, it doesn't work:

process ({ getState, action }, dispatch, done) {
    const id = nextNotificationId++
    dispatch(showNotification(id, action.text))
    setTimeout(() => {
      dispatch(hideNotification(action.id))
      done()
    }, 5000)
  }

[tylerlong]

I also tried

processOptions: {
    dispatchMultiple: true // turn on multiple dispatch mode
  }

It doesn't work either.

[tylerlong]

It is trivial with RxJS:

But this project's goal is:

"I wrote the rxjs code so you won't have to."

I hope this issue could help you to find a balance between abstraction and flexibility.

[jeffbski]

@tylerlong Thanks for creating the issue.

I've put together a jsfiddle that shows how you might do this with redux-logic.

You would use the dispatch and done to perform multiple dispatch, otherwise it assumes a single dispatch. I'm not sure why it didn't work for you when you tried this, but you might compare your own code against the jsfiddle or the snippet below.

http://jsfiddle.net/ezp58328/

let nextNotificationId = 0
const showNotificationWithTimeoutLogic = createLogic({
  type: 'SHOW_NOTIFICATION_WITH_TIMEOUT',
  process ({ getState, action }, dispatch, done) { // include done for multidispatch
    const id = nextNotificationId++
    dispatch(showNotification(id, action.text))
    setTimeout(() => {
      dispatch(hideNotification(id))
      done();
    }, 5000)
  }
});

You could also return an observable if you would prefer to use them. I want people to be able to use whatever they are comfortable with. (callbacks, promises, observables, async/await).

let nextNotificationId = 0
const showNotificationWithTimeoutLogic = createLogic({
  type: 'SHOW_NOTIFICATION_WITH_TIMEOUT',
  process ({ getState, action }) { // can just return an observable too
    const id = nextNotificationId++
    return Observable.merge(
      Observable.of(showNotification(id, action.text)),
      Observable.of(hideNotification(id)).delay(5000)
    );
  }
});

It is a challenge to find the right abstractions for people. I'm always looking to improve them, so I do appreciate advice and suggestions.

[tylerlong]

@jeffbski

I tried again and it did work! I remember that I tried everything possible. Maybe I made some mistake or I forgot to compile the code or clear the cache. I've no idea what was wrong but now it works like a charm!

Here is the sample project I created: https://github.com/tylerlong/hello-async/tree/master/redux-logic Feel free to send me PR if you want to change anything there.

Feel free to close this issue and thank you for the help!

[jeffbski]

Fantastic. I'm glad it worked this time.

I like your project hello-async. It is really good to be able to see different ways to accomplish things side by side.

I'm going to check it out more thoroughly when I have time, but it looks like a great idea.