Update README for ES2015

README.md

@@ -41,44 +41,40 @@ See Matt Andrews' [isomorphic-fetch](https://github.com/matthew-andrews/isomorph
 # Usage
 
 ```javascript
-var fetch = require('node-fetch');
+import fetch from 'node-fetch';
+// or
+// const fetch = require('node-fetch');
 
-// if you are on node v0.10, set a Promise library first, eg.
-// fetch.Promise = require('bluebird');
+// if you are using your own Promise library, set it through fetch.Promise. Eg.
+
+// import Bluebird from 'bluebird';
+// fetch.Promise = Bluebird;
 
 // plain text or html
 
 fetch('https://github.com/')
-	.then(function(res) {
-		return res.text();
-	}).then(function(body) {
-		console.log(body);
-	});
+	.then(res => res.text())
+	.then(body => console.log(body));
 
 // json
 
 fetch('https://api.github.com/users/github')
-	.then(function(res) {
-		return res.json();
-	}).then(function(json) {
-		console.log(json);
-	});
+	.then(res => res.json())
+	.then(json => console.log(json));
 
 // catching network error
 // 3xx-5xx responses are NOT network errors, and should be handled in then()
 // you only need one catch() at the end of your promise chain
 
 fetch('http://domain.invalid/')
-	.catch(function(err) {
-		console.log(err);
-	});
+	.catch(err => console.error(err));
 
 // stream
 // the node.js way is to use stream when possible
 
 fetch('https://assets-cdn.github.com/images/modules/logos_page/Octocat.png')
-	.then(function(res) {
-		var dest = fs.createWriteStream('./octocat.png');
+	.then(res => {
+		const dest = fs.createWriteStream('./octocat.png');
 		res.body.pipe(dest);
 	});
 
@@ -86,18 +82,17 @@ fetch('https://assets-cdn.github.com/images/modules/logos_page/Octocat.png')
 // if you prefer to cache binary data in full, use buffer()
 // note that buffer() is a node-fetch only API
 
-var fileType = require('file-type');
+import fileType from 'file-type';
+
 fetch('https://assets-cdn.github.com/images/modules/logos_page/Octocat.png')
-	.then(function(res) {
-		return res.buffer();
-	}).then(function(buffer) {
-		fileType(buffer);
-	});
+	.then(res => res.buffer())
+	.then(buffer => fileType(buffer))
+	.then(type => { /* ... */ });
 
 // meta
 
 fetch('https://github.com/')
-	.then(function(res) {
+	.then(res => {
 		console.log(res.ok);
 		console.log(res.status);
 		console.log(res.statusText);
@@ -108,22 +103,17 @@ fetch('https://github.com/')
 // post
 
 fetch('http://httpbin.org/post', { method: 'POST', body: 'a=1' })
-	.then(function(res) {
-		return res.json();
-	}).then(function(json) {
-		console.log(json);
-	});
+	.then(res => res.json())
+	.then(json => console.log(json));
 
-// post with stream from resumer
+// post with stream from file
 
-var resumer = require('resumer');
-var stream = resumer().queue('a=1').end();
+import { createReadStream } from 'fs';
+
+const stream = createReadStream('input.txt');
 fetch('http://httpbin.org/post', { method: 'POST', body: stream })
-	.then(function(res) {
-		return res.json();
-	}).then(function(json) {
-		console.log(json);
-	});
+	.then(res => res.json())
+	.then(json => console.log(json));
 
 // post with JSON
 
@@ -133,45 +123,37 @@ fetch('http://httpbin.org/post', {
 	body:    JSON.stringify(body),
 	headers: { 'Content-Type': 'application/json' },
 })
-	.then(function(res) {
-		return res.json();
-	}).then(function(json) {
-		console.log(json);
-	});
+	.then(res => res.json())
+	.then(json => console.log(json));
 
 // post with form-data (detect multipart)
 
-var FormData = require('form-data');
-var form = new FormData();
+import FormData from 'form-data';
+
+const form = new FormData();
 form.append('a', 1);
 fetch('http://httpbin.org/post', { method: 'POST', body: form })
-	.then(function(res) {
-		return res.json();
-	}).then(function(json) {
-		console.log(json);
-	});
+	.then(res => res.json())
+	.then(json => console.log(json));
 
 // post with form-data (custom headers)
 // note that getHeaders() is non-standard API
 
-var FormData = require('form-data');
-var form = new FormData();
+import FormData from 'form-data';
+
+const form = new FormData();
 form.append('a', 1);
 fetch('http://httpbin.org/post', { method: 'POST', body: form, headers: form.getHeaders() })
-	.then(function(res) {
-		return res.json();
-	}).then(function(json) {
-		console.log(json);
-	});
+	.then(res => res.json())
+	.then(json => console.log(json));
 
-// node 0.12+, yield with co
+// node 7+ with async function
 
-var co = require('co');
-co(function *() {
-	var res = yield fetch('https://api.github.com/users/github');
-	var json = yield res.json();
-	console.log(res);
-});
+(async function () {
+	const res = await fetch('https://api.github.com/users/github');
+	const json = await res.json();
+	console.log(json);
+})();
 ```
 
 See [test cases](https://github.com/bitinn/node-fetch/blob/master/test/test.js) for more examples.