Stream mode (fix #1).

10 years ago · 92d6abf9c6
3 changed files with 62 additions and 14 deletions
--- a/index.js
+++ b/index.js
@ -1,31 +1,47 @@
 'use strict';
-var urlLib = require('url');
+
 var http = require('http');
 var https = require('https');
+var urlLib = require('url');
 var zlib = require('zlib');
+var PassThrough = require('stream').PassThrough;
+
 var assign = require('object-assign');

 module.exports = function (url, opts, cb) {
-	var redirectCount = 0;
+	if (typeof opts === 'function') {
+		// If `cb` has been specified but `opts` has not.
+		cb = opts;
+		opts = {};
+	} else if (!opts) {
+		// opts has not been specified.
+		opts = {};
+	}

 	// extract own options
 	var encoding = opts.encoding;
 	delete opts.encoding;

-	var get = function (url, opts, cb) {
-		if (typeof opts === 'function') {
-			cb = opts;
-			opts = {};
-		}
+	// If no callback has been provided, returns a proxy stream to the
+	// response.
+	var proxy;
+	if (!cb) {
+		proxy = new PassThrough();

-		cb = cb || function () {};
-		opts = opts || {};
+		// Forward errors on the stream.
+		cb = function (err) {
+			proxy.emit('error', err);
+		};
+	}

-		opts.headers = assign({
-			'user-agent': 'https://github.com/sindresorhus/got',
-			'accept-encoding': 'gzip,deflate'
-		}, opts.headers || {});
+	// Merge additional headers.
+	opts.headers = assign({
+		'user-agent': 'https://github.com/sindresorhus/got',
+		'accept-encoding': 'gzip,deflate'
+	}, opts.headers || {});

+	var redirectCount = 0;
+	var get = function (url, opts, cb) {
 		var parsedUrl = urlLib.parse(url);
 		var fn = parsedUrl.protocol === 'https:' ? https : http;
 		var arg = assign({}, parsedUrl, opts);
@ -56,6 +72,12 @@ module.exports = function (url, opts, cb) {
 				res = unzip;
 			}

+			// If in proxy mode, simply pipe the response to the proxy.
+			if (proxy) {
+				res.pipe(proxy);
+				return;
+			}
+
 			res.once('error', cb);

 			var chunks = [];
@ -79,4 +101,5 @@ module.exports = function (url, opts, cb) {
 	};

 	get(url, opts, cb);
+	return proxy;
 };
--- a/readme.md
+++ b/readme.md
@ -21,12 +21,15 @@ $ npm install --save got
 ```js
 var got = require('got');

+// Callback mode.
 got('http://todomvc.com', function (err, data, res) {
 	console.log(data);
 	//=> <!doctype html> ...
 });
-```

+// Stream mode.
+got('http://todomvc.com').pipe(fs.createWriteStream('index.html'));
+```

 ### API

--- a/test.js
+++ b/test.js
@ -66,3 +66,25 @@ it('should return a buffer if encoding is set to null', function (done) {
 		done();
 	});
 });
+
+it('should return a readable stream without a callback', function (done) {
+	var stream = got('http://google.com');
+
+	var data = '';
+	stream.on('data', function (chunk) {
+		data += chunk;
+	});
+	stream.on('end', function () {
+		assert.ok(/google/.test(data));
+		done();
+	});
+});
+
+it('should proxy errors to the stream', function (done) {
+	var stream = got('http://sindresorhus.com/sfsadfasdfadsga');
+
+	stream.on('error', function (error) {
+		assert.strictEqual(error, 404);
+		done();
+	});
+});