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XLT (Xceptance LoadTest) is an extensive load and performance test tool developed and maintained by Xceptance.

There is a newer version: 8.4.1

# window.fetch polyfill

The `fetch()` function is a Promise-based mechanism for programmatically making
web requests in the browser. This project is a polyfill that implements a subset
of the standard [Fetch specification][], enough to make `fetch` a viable
replacement for most uses of XMLHttpRequest in traditional web applications.

## Table of Contents

* [Read this first](#read-this-first)
* [Installation](#installation)
* [Usage](#usage)
  * [Importing](#importing)
  * [HTML](#html)
  * [JSON](#json)
  * [Response metadata](#response-metadata)
  * [Post form](#post-form)
  * [Post JSON](#post-json)
  * [File upload](#file-upload)
  * [Caveats](#caveats)
    * [Handling HTTP error statuses](#handling-http-error-statuses)
    * [Sending cookies](#sending-cookies)
    * [Receiving cookies](#receiving-cookies)
    * [Redirect modes](#redirect-modes)
    * [Obtaining the Response URL](#obtaining-the-response-url)
    * [Aborting requests](#aborting-requests)
* [Browser Support](#browser-support)

## Read this first

* If you believe you found a bug with how `fetch` behaves in your browser,
  please **don't open an issue in this repository** unless you are testing in
  an old version of a browser that doesn't support `window.fetch` natively.
  Make sure you read this _entire_ readme, especially the [Caveats](#caveats)
  section, as there's probably a known work-around for an issue you've found.
  This project is a _polyfill_, and since all modern browsers now implement the
  `fetch` function natively, **no code from this project** actually takes any
  effect there. See [Browser support](#browser-support) for detailed
  information.

* If you have trouble **making a request to another domain** (a different
  subdomain or port number also constitutes another domain), please familiarize
  yourself with all the intricacies and limitations of [CORS][] requests.
  Because CORS requires participation of the server by implementing specific
  HTTP response headers, it is often nontrivial to set up or debug. CORS is
  exclusively handled by the browser's internal mechanisms which this polyfill
  cannot influence.

* This project **doesn't work under Node.js environments**. It's meant for web
  browsers only. You should ensure that your application doesn't try to package
  and run this on the server.

* If you have an idea for a new feature of `fetch`, **submit your feature
  requests** to the [specification's repository](https://github.com/whatwg/fetch/issues).
  We only add features and APIs that are part of the [Fetch specification][].

## Installation

```
npm install whatwg-fetch --save
```

As an alternative to using npm, you can obtain `fetch.umd.js` from the
[Releases][] section. The UMD distribution is compatible with AMD and CommonJS
module loaders, as well as loading directly into a page via `