redux-thunk-generator

import _ from "lodash";
import {fn as isGeneratorFn} from "is-generator";

const generatorMiddleware = store => next => action => {
  let {dispatch} = store;
  let generator = findGenerator(action);
  if(isGeneratorFn(action)){
    return runGenerator(dispatch, action, action);
  }
  else if(generator){
    return runGenerator(dispatch, action, generator);
  }
  return next(action);
};

export default generatorMiddleware;

/*
  helper zone
*/
function runGenerator(dispatch, action, generator){
  let iterator = generator();
  function handle(result, ite){
    let value = result.value;
    if(value){
      if(typeof value === "object" && "then" in value){
        value.then((res) =>  dispatchActualAction(dispatch, action, res));
      }
      else{
        dispatchActualAction(dispatch, action, value);
      }
    }
    if(result.done){ return Promise.resolve(value); }
    return Promise.resolve(value).then((res) => handle(ite.next(res), ite));
  }
  return handle(iterator.next(), iterator);
}

function findGenerator(action, onFound){
  if(action.performAction && isGeneratorFn(action.performAction)){
    onFound && onFound(action);
    return action.performAction;
  }
  else if(action.performAction){
    return findGenerator(action.performAction, callbackOnFound);
  }
  return null;
}

function dispatchActualAction(dispatch, action, actualAction){
  if(isGeneratorFn(action)){
    dispatch(actualAction);
  }
  else{
    let clonedAction = _.cloneDeep(action);
    findGenerator(clonedAction, (parentAction) => { parentAction.performAction = actualAction; });
    dispatch(clonedAction);
  }
}