在 useEffect 未运行时取消 Axios 请求 [英] Cancel Axios request in useEffect not running

问题描述

我正在尝试取消 axios 请求，但我只取得了部分成功.我有这个函数在我发出 GET 请求时返回一个 Promise:

I am attempting to cancel an axios request, but I am only having partial success. I have this function that returns a Promise when I make a GET request:

const getCards = (token) => {
  const URL = isDev
    ? "https://cors-anywhere.herokuapp.com/https://privacy.com/api/v1/card"
    : "https://privacy.com/api/v1/card";
  const config = {
    headers: {
      Authorization: `Bearer ${token}`,
    },
    cancelToken: source.token,
  };

  return axios.get(URL, config);
};

我在 updateCards() 中调用这个函数，它看起来像这样:

I call this function inside updateCards() which looks like this:

const updateCards = async () => {
  console.log("Updating Cards");

  setCards([]);
  setStarted(true);
  setLoading(true);

  let response = await getCards(token).catch((thrown) => {
    if (axios.isCancel(thrown)) {
      console.error("[UpdateCards]", thrown.message);
    }
  });

  /**
   * response is undefined when we cancel the request on unmount
   */

  if (typeof response === "undefined") return console.log("Undefined");

  console.log("Got Response from UpdateCards", response);

  setLoading(false);
};

我在 useEffect 钩子中取消了我的请求:

I cancel my request in the useEffect hook as so:

useEffect(() => {
    return () => {
        source.cancel()
    }
}, [])

我已经在我的状态声明下设置了我的 CancelToken，如下所示:

And I have setup my CancelToken under my state declaration like this:

const CancelToken = axios.CancelToken;
const source = CancelToken.source();

我的问题是，如果我在 useEffect() 内部调用我的 updateCards() 函数，我可以很好地取消它，但是如果我使用按钮来调用相同的函数，则不会运行取消.我到处寻找，我发现的唯一解决方案是我必须在 useEffect() 挂钩中调用我的请求，但这不是我想做的事情.我该从哪里开始?

My issue is that, if I call my updateCards() function inside of the useEffect(), I can cancel it just fine, but if I use a button to call that same function the cancel is not ran. I have looked everywhere and the only solution I have found is that I have to call my requests within the useEffect() hook, but that is not something I want to do.Where do I go from here?

以下是我看过的资源:

https://github.com/axios/axios#cancellation

https://medium.com/@selvaganesh93/how-to-clean-up-subscriptions-in-react-components-using-abortcontroller-72335f19b6f7

无法通过CancelToken取消Axios post请求

推荐答案

有一个地方来存储一个变量，其行为类似于 实例变量，可以使用useRef.它是您想要的任何东西的容器.您可以将 CancelToken 存储在那里:

To have a place to store a variable that behaves like an instance variable of the component, you can use useRef. It's a container for anything you want. You can store the CancelToken in there:

function Privacy(props) {
  const source = useRef(null);

  function getSource() {
    if (source.current == null) {
      const CancelToken = axios.CancelToken;
      source.current = CancelToken.source();
    }
    return source.current;
  }

  useEffect(() => {
    return () => {
      if (source.current != null) source.current.cancel();
    }
  }, [])

  // call `getSource()` wherever you need the Axios source
}

这篇关于在 useEffect 未运行时取消 Axios 请求的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！