fetch() cheatsheet

fetch('/data.json') .then(res => { res.text() // response body (=> Promise) res.json() // parse via JSON (=> Promise) res.status //=> 200 res.statusText //=> 'OK' res.redirected //=> false res.ok //=> true res.url //=> 'http://site.com/data.json' res.type //=> 'basic' // ('cors' 'default' 'error' // 'opaque' 'opaqueredirect') res.headers.get('Content-Type') }) 

fetch('/data.json', { method: 'post', body: new FormData(form), // post body body: JSON.stringify(...), headers: { 'Accept': 'application/json' }, credentials: 'same-origin', // send cookies credentials: 'include', // send cookies, even in CORS }) 

fetch('/data.json') .then(checkStatus) 

function checkStatus (res) { if (res.status >= 200 && res.status < 300) { return res } else { let err = new Error(res.statusText) err.response = res throw err } } 

Non-2xx responses are still successful requests. Use another function to turn them to errors.

const fetch = require('isomorphic-fetch') 

See: isomorphic-fetch (npmjs.com)