Tiny 500b fetch "barely-polyfill"

• Tiny: under 500 bytes of ES3 gzipped
• Minimal: just fetch() with headers and text/json/xml responses
• Familiar: a subset of the full API
• Supported: supports IE8+ (assuming Promise is polyfilled of course!)
• Standalone: one function, no dependencies
• Modern: written in ES2015, transpiled to 500b of old-school JS

🤔 What's Missing?

• Uses simple Arrays instead of Iterables, since Arrays are iterables
• No streaming, just Promisifies existing XMLHttpRequest response bodies

• Install
• Usage
• Examples & Demos
• API
• Contribute
• License

This project uses node and npm. Go check them out if you don't have them locally installed.

$ npm install --save unfetch

Then with a module bundler like rollup or webpack, use as you would anything else:

// using ES6 modules
import fetch from 'unfetch'

// using CommonJS modules
var fetch = require('unfetch')

The UMD build is also available on unpkg:

<script src="//unpkg.com/unfetch/dist/unfetch.umd.js"></script>

This exposes the unfetch() function as a global.

As a ponyfill:

import fetch from 'unfetch';

fetch('/foo.json')
  .then( r => r.json() )
  .then( data => {
    console.log(data);
  });

Globally, as a polyfill:

import 'unfetch/polyfill';

// "fetch" is now installed globally if it wasn't already available

fetch('/foo.json')
  .then( r => r.json() )
  .then( data => {
    console.log(data);
  });

Real Example on JSFiddle ➡️

// simple GET request:
fetch('/foo')
  .then( r => r.text() )
  .then( txt => console.log(txt) )


// complex POST request with JSON, headers:
fetch('/bear', {
  method: 'POST',
  headers: {
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({ hungry: true })
}).then( r => {
  open(r.headers.get('location'));
  return r.json();
})

First off, thanks for taking the time to contribute! Now, take a moment to be sure your contributions make sense to everyone else.

Found a problem? Want a new feature? First of all see if your issue or idea has already been reported. If it hasn't, just open a new clear and descriptive issue.

Pull requests are the greatest contributions, so be sure they are focused in scope, and do avoid unrelated commits.

💁 Remember: size is the #1 priority.

Every byte counts! PR's can't be merged if they increase the output size much.

• Fork it!
• Clone your fork: git clone https://github.com/<your-username>/unfetch
• Navigate to the newly cloned directory: cd unfetch
• Create a new branch for the new feature: git checkout -b my-new-feature
• Install the tools necessary for development: npm install
• Make your changes.
• npm run build to verify your change doesn't increase output size.
• npm test to make sure your change doesn't break anything.
• Commit your changes: git commit -am 'Add some feature'
• Push to the branch: git push origin my-new-feature
• Submit a pull request with full remarks documenting your changes.

MIT License © Jason Miller