Question

如何取消订阅Relay Modern中的订阅？

我已经关注了How to GraphQL React + Relay上的订阅教程，但是没有提及你如何取消订阅Relay Modern网站。

任何帮助都会很棒。

更新----------

根据Lee Byron（see GitHub issue），您只需致电dispose() 在requestSubscription()

上

对示例进行以下修改后：

./ src / subscriptions / NewVoteSubscription.js （将return添加到requestSubscription）

export default () => {
    const subscriptionConfig = {
    subscription: newVoteSubscription,
    variables: {},
    updater: proxyStore => {
        const createVoteField = proxyStore.getRootField('Vote')
        const newVote = createVoteField.getLinkedRecord('node')
        const updatedLink = newVote.getLinkedRecord('link')
        const linkId = updatedLink.getValue('id')
        const newVotes = updatedLink.getLinkedRecord('_votesMeta')
        const newVoteCount = newVotes.getValue('count')

        const link = proxyStore.get(linkId)
        link.getLinkedRecord('votes').setValue(newVoteCount, 'count')
    },
    onError: error => console.log(`An error occured:`, error)
  }

  return requestSubscription(
      environment,
      subscriptionConfig
  )

./ src / components / LinkList.js （在组件上设置订阅，然后使用componentWillUnmount到dispose()）

componentDidMount() {
    this.subscription = NewVoteSubscription()
}

componentWillUnmount() {
    this.subscription.dispose()
}

这是我得到的错误：

Uncaught TypeError: Cannot read property 'dispose' of undefined
    at RelayObservable.js:94
    at doCleanup (RelayObservable.js:453)
    at Object.unsubscribe (RelayObservable.js:474)
    at RelayObservable.js:330
    at doCleanup (RelayObservable.js:453)
    at Object.unsubscribe (RelayObservable.js:474)
    at doCleanup (RelayObservable.js:450)
    at Object.unsubscribe [as dispose] (RelayObservable.js:474)
    at LinkList.componentWillUnmount (LinkList.js:18)
    at callComponentWillUnmountWithTimerInDev (react-dom.development.js:11123)
    at HTMLUnknownElement.callCallback (react-dom.development.js:1309)
    at Object.invokeGuardedCallbackDev (react-dom.development.js:1348)
    at invokeGuardedCallback (react-dom.development.js:1205)
    at safelyCallComponentWillUnmount (react-dom.development.js:11131)
    at commitUnmount (react-dom.development.js:11421)
    at unmountHostComponents (react-dom.development.js:11362)
    at commitDeletion (react-dom.development.js:11392)
    at commitAllHostEffects (react-dom.development.js:12279)
    at HTMLUnknownElement.callCallback (react-dom.development.js:1309)
    at Object.invokeGuardedCallbackDev (react-dom.development.js:1348)
    at invokeGuardedCallback (react-dom.development.js:1205)
    at commitAllWork (react-dom.development.js:12384)
    at workLoop (react-dom.development.js:12695)
    at HTMLUnknownElement.callCallback (react-dom.development.js:1309)
    at Object.invokeGuardedCallbackDev (react-dom.development.js:1348)
    at invokeGuardedCallback (react-dom.development.js:1205)
    at performWork (react-dom.development.js:12808)
    at batchedUpdates (react-dom.development.js:13262)
    at performFiberBatchedUpdates (react-dom.development.js:1656)
    at stackBatchedUpdates (react-dom.development.js:1647)
    at batchedUpdates (react-dom.development.js:1661)
    at Object.batchedUpdatesWithControlledComponents [as batchedUpdates] (react-dom.development.js:1674)
    at dispatchEvent (react-dom.development.js:1884)

Answer 1

并设置RelayEnvironment

function setupSubscription(config, variables, cacheConfig, observer) {
  const query = config.text;

  const subscriptionClient = new SubscriptionClient(websocketURL, {
    reconnect: true
  });

  const client = subscriptionClient.request({ query, variables }).subscribe({
    next: result => {
      observer.onNext({ data: result.data });
    },
    complete: () => {
      observer.onCompleted();
    },
    error: error => {
      observer.onError(error);
    }
  });

  return {
    dispose: client.unsubscribe
  };
}

Answer 2

由于relay-modern@6，您需要返回observable，否则将由于以下错误而崩溃：RelayObservable: Unhandled Error TypeError: source.subscribe is not a function

代替

return {
    dispose: client.unsubscribe
};

您需要退货

return Observable.create(() => {
  // return cleanup function
  return yourFunctionToCleanUp;
});

可以从relay-runtime导入的地方。

赞：

import {
  Observable,
} from 'relay-runtime';

因此，当您实际上在this.subscription.dispose()中调用componentWillUnmount时，它将调用函数yourFunctionToCleanUp()。

如何在Relay Modern

2 个答案: