index.js.flow

// @flow
import XXH from 'xxhashjs';
import produce from 'immer';
import _ from 'lodash';

export const CANCELED_REQUEST_ENABLED = 'CANCELED_REQUEST_ENABLED';
export const REMOVE_CANCELED_CURRENT_REQUEST_FROM_STORE = 'REMOVE_CANCELED_CURRENT_REQUEST_FROM_STORE';

/**
 * Generate an IdRequest based on xxhashjs
 */
export const generateId = (futureId: any) => XXH.h32(futureId, '0xABCD').toString(16);

/**
 * Dispatch a cancelable dispatch
 */
export const cancelRequestDispatch = (dispatch: Function, idToCancel: any) => dispatch({
  type: CANCELED_REQUEST_ENABLED,
  idRequestToCancel: generateId(idToCancel),
});

/**
 * Cancelable is a specific function to allow a method cancel in
 * a component.
 */
export const cancelable = (dispatch: Function, myFunction: Function, id: any) => {
  myFunction.cancel = () => {
    cancelRequestDispatch(dispatch, id);
  };
  return myFunction;
};

/**
 * Redux middleware to handle canceledRequestInReducer
 */
export const cancelRequestMiddleware = ({ getState }) => (next: Function) => (action: Object) => {
  const state = getState();
  const canceledRequestsState = _.get(state, '_canceledRequest.requests');
  if (canceledRequestsState) {
    if (action.idRequest) {
      const foundTheRequest = canceledRequestsState.find(
        requestRegistered => requestRegistered === action.idRequest,
      );
      if (foundTheRequest) {
        action.canceled = true;
        next(action);
        next({
          type: REMOVE_CANCELED_CURRENT_REQUEST_FROM_STORE,
          payload: action.idRequest,
        });
        return next;
      }
    }
  }
  const returnValue = next(action);
  return returnValue;
};

/**
 * Export a reducer wich can be include
 * in a redux store
 */
// eslint-disable-next-line
export const _canceledRequest = (
  state: Object = {
    requests: [],
  },
  action: Object,
) => produce(state, (draft) => {
  switch (action.type) {
    case REMOVE_CANCELED_CURRENT_REQUEST_FROM_STORE: {
      const findIndex = draft.requests.findIndex(aRequest => aRequest === action.payload);
      draft.requests.splice(findIndex, 1);
      break;
    }
    case CANCELED_REQUEST_ENABLED:
      draft.requests.push(action.idRequestToCancel);
      break;

    default:
      break;
  }
  return draft;
});