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import axios, { Canceler } from "axios";
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import * as React from "react";
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const fetchData = async (cancelToken: CancelToken) => {
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  try {
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    const response = await axios.get("http://my-endpoint.com/api/sample", {
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      headers: {
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        "Content-Type": "application/json",
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      },
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      /**
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       * Pass the cancel token in the axios get call
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       */
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      cancelToken,
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    });
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    return response;
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  } catch (error) {
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    throw error;
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  }
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};
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type DataContextValue = ReturnType<typeof useData>;
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export const DataContext = React.createContext<DataContextValue | undefined>(
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  undefined
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);
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const useData = () => {
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  const [data, setData] = React.useState<number>(0);
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  /**
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   * Create a React ref to store the cancel token
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   */
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  const cancelDataRequest = React.useRef<Canceler>();
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  const getData = React.useCallback(async () => {
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    /**
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     * If a cancel token is already present: call it to cancel any previous
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     * call of fetchData that is still in progress
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     */
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    cancelDataRequest.current && cancelDataRequest.current();
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    /**
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     * Create a new axios cancel token and assign it the React ref
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     */
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    const cancelToken = new axios.CancelToken((c) => {
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      cancelDataRequest.current = c;
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    });
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    try {
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      const data = await fetchData(cancelToken);
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      setData(data);
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    } catch (e) {
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      throw e;
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    }
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    return data;
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  }, [data]);
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  return {
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    getData,
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    data,
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  };
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};
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/**
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 * React context provider that will give access to data
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 * and getData to any DataContext consumer
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 */
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const DataProvider: React.FC = (props) => {
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  const value = useData();
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  return (
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    <DataContext.Provider value={value}>{props.children}</DataContext.Provider>
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  );
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};