Function default

Adds the ability to measure requests using the Performance Timings API.

Uses the Performance API (browsers & node.js) to expose timings related to the underlying request.

Browser timings are very accurate, node.js only contains raw measures.

import PerfsAddon from "wretch/addons/perfs"

// Use perfs() before the response types (text, json, ...)
wretch("...")
  .addon(PerfsAddon())
  .get()
  .perfs((timings) => {
    // Will be called when the timings are ready.
console.log(timings.startTime);
  })
  .res();

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For node.js, there is a little extra work to do :

// Node.js only
const { performance, PerformanceObserver } = require("perf_hooks");

wretch.polyfills({
  fetch: function (url, opts) {
    performance.mark(url + " - begin");
    return fetch(url, opts).then(res => {
      performance.mark(url + " - end");
      setTimeout(() => performance.measure(res.url, url + " - begin", url + " - end"), 0);
      return res;
    });
  },
  // other polyfills…
  performance: performance,
  PerformanceObserver: PerformanceObserver,
});
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