43 lines
1.4 KiB
JavaScript
43 lines
1.4 KiB
JavaScript
import React, { useEffect, useState } from 'react';
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import axios from 'axios';
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import PropTypes from 'prop-types';
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//destructure props
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const Card = ({name}) => {
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/*store count as array in function component state*/
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/*initialise as empty array*/
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const [count, setCount] = useState(null);
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/*fetch count in a JavaScript function*/
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const getCount = async () => {
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try {
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/*TODO make route available using config*/
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/*TODO handle errors: https://www.valentinog.com/blog/await-react/*/
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const address=`https://www.v1gtfs.delfi.api.swingbe.de/table-${name}-count`;
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const count = await axios.get(address);
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/*set state*/
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setCount(count.data[0]['count']);
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} catch (err) {
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console.log('err.message: ' + err.message);
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}
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};
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/*this hook is run after a DOM update. Changing state migh result in an infinite loop*/
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useEffect(() => {
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/*effect goes here*/
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/*hook need to be placed in body of the function component in which it is used*/
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getCount();
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/*use an empty dependency array to ensure the hook is running only once*/
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/*TODO study dependency array: https://reactjs.org/docs/hooks-effect.html*/
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}, []);
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return <p>{name}: {count?count:'loading...'}</p>;
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};
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Card.propTypes = {
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name: PropTypes.string
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};
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export default Card;
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