xhfetch

Tiny cancellable fetch

• Tiny: about 600 bytes of ES3 gzipped
• Familiar: uses common fetch and XMLHttpRequest api
• Supported: supports IE8+ (assuming Promise is polyfilled)

Installation

npm install xhfetch

Usage

No Cancellation

import { createRequest } from 'xhfetch';

// createRequest accepts same parameter as window.fetch
createRequest('https://api.github.com/users', {
    headers: {
        'Accept': 'application/json',
    },
})
  .fetch() // the api request will only be invoked when you call `fetch`
  .then(res => res.json());
  .then(users => console.log(users))

With Cancellation

import { createRequest } from 'xhfetch';

const { xhr, fetch } = createRequest('https://api.github.com/users', {
    headers: {
        'Accept': 'application/json',
    },
})

fetch()
  .then(res => res.json());
  .then(users => console.log(users))

setTimeout(() => {
    // cancels if the request takes more than a second
    xhr.abort();
}, 1000)

Examples

• React API calls in effect hooks and cancel

API

The goal of Xhfetch is to provide a familiar interface while keeping small size, therefore we only focus on a subset of fetch API that is most commonly used.

createRequest(url: string, options: Object) => { fetch, xhr }

Specify a request that you want to make and get a fetch function and a XMLHttpRequest object. The following properties in options will be accounted:

• method
• headers
• credentials: Accepts a "include" string, which will allow both CORS and same origin requests to work with cookies. Xhfetch won't send or receive cookies otherwise. The "same-origin" value is not supported (just don't set it if it's same-origin).
• body: The content to be transmitted in request's body. Common content types include FormData, JSON, Blob, ArrayBuffer or plain text.

.fetch()

The fetch function returns by createRequest does not accepts any parameter. Invoking this call will kicks off the API request and returns a response object in the Promise chain. The response object contains a subset of Response class functionality:

• response.ok
• response.status
• response.statusText
• response.clone()
• response.text(), response.json(), response.blob()
• response.headers

.xhr

The xhr object returns by createRequest is the underlying XMLHttpRequest object that is making the request, therefore you have access to all methods available for XMLHttpRequest, e.g. .abort() and .addEventListener()

License

MIT

Acknowledgements

• The code of xhfetch is based on unfetch.