I study patterns used in an open source project found on Github Trending. For this week, I reviewed some parts of Meshery codebase and wrote this article.
You will find this function’s definition in lib/data-fetch, evident from the import
/** * promisifiedDataFetch adds a promise wrapper to the dataFetch function * and ideal for use inside async functions - which is most of the functions * @param {string} url url is the endpoint * @param {Record<string, any>} options HTTP request options * @returns */export function promisifiedDataFetch(url, options = {}) { return new Promise((resolve, reject) => { dataFetch( url, options, (result) => resolve(result), (err) => reject(err), ); });}
The comment above is pretty self explanatory. I would be more interested in finding out how this dataFetch method is defined. This dataFetch function is defined in the same file at the top and is defined as shown below:
const dataFetch = (url, options = {}, successFn, errorFn) => { // const controller = new AbortController(); // const signal = controller.signal; // options.signal = signal; // setTimeout(() => controller.abort(), 10000); // nice to have but will mess with the load test if (errorFn === undefined) { errorFn = (err) => { console.error(`Error fetching ${url} --DataFetch`, err); }; } fetch(url, options) .then((res) => { if (res.status === 401 || res.redirected) { if (window.location.host.endsWith('3000')) { window.location = '/user/login'; // for local dev thru node server } else { window.location.reload(); // for use with Go server } } let result; if (res.ok) { result = res.text().then((text) => { try { return JSON.parse(text); } catch (e) { return text; } }); return result; } else { throw res.text(); } }) .then(successFn) .catch((e) => { if (e.then) { e.then((text) => errorFn(text)); return; } errorFn(e); });};
