redux-bus/src/handle.js

queueing, stacking, buffering, network state validation and undoing actions redux middleware

export default  (handlers, options, store, next, action, current) => {
  const {handler:name} = current
  let handler = handlers[name]
  let handlerOptions = options[name]

  if (handler) {
    // bus has not been initialized, so it must be validated..
    let bus = store.getState().bus || {}

    // queue is an object
    // so it can has properties
    // other that just buffer
    // for future possible features..
    let queue = bus[handler] || {buffer: []}

    // the handler is attached and passed along
    // so we take it out of the action
    action = Object.assign({}, action)

    // this handler will take a queue and must return a queue
    queue =  handler(handlerOptions, store, next, action, queue, current)

    // add validation that the return of the handler is queue
    if (!queue.buffer || !queue.buffer.length) return

    // actions to update the buffer
    action = {
      type: '@@bus/UPDATE_QUEUE',
      payload: {
        queue,
        handler,
      },
    }
    store.dispatch(action)

  } else next(action)

}