AsyncAction

public protocol AsyncAction: Action

Async action this type of action is intercepted by AsyncMiddleware and is not dispatched to the reducer.

Recepie to use AsyncAction

1. Create an AsyncAction action
2. In the block passed at init. Perform any operation (dispatching it on your queue)
3. When result is ready, call dispatch passing a new action

If the AsyncMiddleware receives an AsyncAction it does the following:

1. Call action.execute passing in the dispatch and get state functions
2. Stops the action from propagating to other middlewares and reducers

Example

Performing an async loading from disk

struct MyDiskAsyncAction: AsyncAction {

  func execute(getState: @escaping GetStateFunction, dispatch: @escaping DispatchFunction) {
    // Perform some work in a background thread
    DispatchQueue(label: "MyQueue").async {
      // Load from disk
      // Process loaded
      // Do more work

      // Maybe consult the current state
      let currentState = api.state

      // At a latter time dont forget to dispatch
      dispatch(DataLoadedAction(data: data))
    }
}

store.dispatch(action: MyDiskAsyncAction())

Performing an async network request

struct MyURLAsyncAction: AsyncAction {

  func execute(getState: @escaping GetStateFunction, dispatch: @escaping DispatchFunction) {
    // First dispatch some action syncrhonously
    dispatch(SomeAction(...))

    let session = URLSession(configuration: .default)
    // perform a dataTask
    session.dataTask(with: urlRequest) { data, response, error in

      if let data = data {
        // Do something with the data
         dispatch(RequestSucceeded(data: data))

      } else if let error = error {

         // Error happenend
         dispatch(RequestFaile(data: data))
      }
   }
}

store.dispatch(action: MyURLAsyncAction())