startSubscription 从未调用过

Question

我正在尝试使用 meteor redux 中间件。按照教程一步步进行，但到目前为止还没有成功。问题似乎出在 startSubscription 上：我永远看不到调用的 get() 和 subscribe() 函数，我在浏览器和服务器终端中插入了空的控制台调用。

// actions.js
import { Meteor } from 'meteor/meteor';
import { startSubscription } from 'meteor-redux-middlewares';
import FaucetRewards from '/imports/api/Rewards/Rewards.js';

export const HOME_REWARDS_SUBSCRIPTION_READY = 'HOME_REWARDS_SUBSCRIPTION_READY';
export const HOME_REWARDS_SUBSCRIPTION_CHANGED = 'HOME_REWARDS_SUBSCRIPTION_CHANGED';
export const HOME_REWARDS_SUB = 'rewards';

export const loadRewards = () =>{

  console.log("actions.loadRewards()"); // I can see this

  let sub = Meteor.subscribe(HOME_REWARDS_SUB); // I can see this in server console and in the sub variable below

  console.log(sub);

  console.log(FaucetRewards.find().fetch()); // Sub is not performed in time, so this is empty as expected

  return(
    startSubscription({
      key: HOME_REWARDS_SUB,
      get: () => { 
        console.log("loadRewards.startSubscription.get()"); // I can never see this
        return (FaucetRewards.find().fetch())
      },
      subscribe: () => {  
        console.log("loadRewards.startSubscription.subcribe()"); // I can never see this
        let subscription = Meteor.subscribe(HOME_REWARDS_SUB); 
        return subscription;
      }
    })
  );

};

我可能忽略了一些愚蠢的事情。有人可以帮我吗？

Answer 1

终于意识到问题了

首先，我的 store.js 文件有问题。具体来说，我不小心删除了与 createReactiveMiddlewares 相关的行。

const { sources, subscriptions, } = createReactiveMiddlewares(Tracker);

然后，在实现 actions.js 时，您必须非常注意动作的命名以及必须根据动作命名的 Meteor.subscribe 方法。下面的示例，如果 HOME_POSTS_SUB 等于 "home_randomName"，它将不起作用，因为 _SUBSCRIPTION_READY 和 _SUBSCRIPTION_CHANGED 前缀必须与 _SUB 字符串值一致。

export const HOME_POSTS_SUBSCRIPTION_READY = 'HOME_POSTS_SUBSCRIPTION_READY'; export const HOME_POSTS_SUBSCRIPTION_CHANGED = 'HOME_POSTS_SUBSCRIPTION_CHANGED'; export const HOME_POSTS_SUB = 'home.posts'; // will work! //export const HOME_POSTS_SUB = 'home.randomName'; // spoiled!! //export const HOME_POSTS_SUB = 'posts'; // spoiled!!

export const loadHomePosts = () => startSubscription({ key: HOME_POSTS_SUB, subscribe: () => Meteor.subscribe(HOME_POSTS_SUB), get: () => Posts.find().fetch(),

naming HOME_POSTS_... differently will give you a hell lot of troubles later. So, naming the actions correctly has an effect later when you use them in the reducer.js file:

export function home(state = initialState, action) { switch (action.type) { case HOME_POSTS_SUBSCRIPTION_READY: return { ...state, ready: action.payload.ready, postsSubscriptionStopped: false, }; case HOME_POSTS_SUBSCRIPTION_CHANGED: return { ...state, posts: action.payload, }; case STOP_SUBSCRIPTION: return action.payload === HOME_POSTS_SUB ? { ...state, postsSubscriptionStopped: true } : state; default: return state; } }

startSubscription 从未调用过

startSubscription never called in action

meteor

reactjs

redux