javascript - fetch api retry if http request fails -


i'm using browser's native fetch api network requests. using whatwg-fetch polyfill unsupported browsers.

however need retry in case request fails. there npm package whatwg-fetch-retry found, haven't explained how use in docs. can me or suggest me alternative?

from official fetch docs :

fetch('/users')     .then(checkstatus)     .then(parsejson)     .then(function(data) {           console.log('succeeded', data)     }).catch(function(error) {           console.log('request failed', error)     })

see catch? trigger when fetch fails, can fetch again there example.

have @ promises https://developer.mozilla.org/en-us/docs/web/javascript/reference/global_objects/promise

edit: add working example should return result. have tried in chrome (v.60.0) , didn't use polyfill nor package mention (after reading docs seems fork fetch polifyll).

function fetchretry(url, delay, limit, fetchoptions = {}) {     return new promise((resolve,reject) => {         function success(response) {             resolve(response);         }         function failure(error){             limit--;             if(limit){                 settimeout(fetchurl,delay)             }             else {                 // time failed real                 reject(error);             }         }         function finalhandler(finalerror){             throw finalerror;         }         function fetchurl() {             return fetch(url,fetchoptions)                 .then(success)                 .catch(failure)                 .catch(finalhandler);         }         fetchurl();     }); }  fetchretry('https://www.google.es',1000,4)      .then(function(response){        if(!response.ok){            throw new error('failed!');        }        return response;    })    .then(function(response){        console.log(response);    })    .catch(function(error){        console.log(error);     });

haven't tested if retry attempts return response suppose do.

edit: found package replaces fetch api i'm not pretty sure that, https://www.npmjs.com/package/fetch-retry (there 2 more packages 1 in first google results page fetch-retry...)


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