订阅字段必须返回异步Iterable。收到：[职能]

Question

我正在尝试过滤订阅，以确保每个客户端只接收他们需要的数据。但是，当我使用此实现时，会出现一个错误。

/**
 * Relevant packages and their versions
 *     "apollo-server-core": "^3.6.2",
 *     "apollo-server-koa": "^3.6.2",
 *     "graphql": "^16.3.0",
 *     "graphql-request": "^3.7.0",
 *     "graphql-subscriptions": "^2.0.0",
 *
 *
 */
const Subscription = {
  agentLocation: {
    type: AgentLocationType,
    args: {
      id: { type: GraphQLID },
    },
    resolve: (payload) => {
      console.log(payload, ' is the payload')
      return payload.agentLocation
    },
    subscribe: withFilter(
      () => pubsub.asyncIterator('LOCATION_UPDATED'),
      (payload, variables) => {
        return payload.agentLocation.id === variables.id
      }
    ),
  },
}

阿波罗演播室显示了这个错误

​

我做错了什么？

Answer 1

我不记得我到底做了什么，但我现在拥有的是为我工作的片段。不过，我不使用图形瑜伽。

const { PubSub, withFilter } = require('graphql-subscriptions')

const { GraphQLID } = require('graphql')
const pubsub = new PubSub()
const Subscription = {
  agentLocation: {
    type: AgentLocationType,
    args: {
      id: { type: GraphQLID },
    },
    resolve: (payload) => {
      return payload.agentLocation
    },
    subscribe: withFilter(
      () => pubsub.asyncIterator('LOCATION_UPDATED'),
      (payload, variables) => {
        return payload.agentLocation.id === variables.id
      }
    ),
  },
}