Wed, 31 Dec 2014 06:09:35 +0100
Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.
1 var expect = require('chai').expect;
2 var util = require('./util');
4 var Flow = require('../lib/flow').Flow;
6 function createFlow(log) {
7 var flowControlId = util.random(10, 100);
8 var flow = new Flow(flowControlId);
9 flow._log = util.log.child(log || {});
10 return flow;
11 }
13 describe('flow.js', function() {
14 describe('Flow class', function() {
15 var flow;
16 beforeEach(function() {
17 flow = createFlow();
18 });
20 describe('._receive(frame, callback) method', function() {
21 it('is called when there\'s a frame in the input buffer to be consumed', function(done) {
22 var frame = { type: 'PRIORITY', flags: {}, priority: 1 };
23 flow._receive = function _receive(receivedFrame, callback) {
24 expect(receivedFrame).to.equal(frame);
25 callback();
26 };
27 flow.write(frame, done);
28 });
29 it('has to be overridden by the child class, otherwise it throws', function() {
30 expect(flow._receive.bind(flow)).to.throw(Error);
31 });
32 });
33 describe('._send() method', function() {
34 it('is called when the output buffer should be filled with more frames and the flow' +
35 'control queue is empty', function() {
36 var sendCalled = 0;
37 var notFlowControlledFrame = { type: 'PRIORITY', flags: {}, priority: 1 };
38 flow._send = function _send() {
39 sendCalled += 1;
40 this.push(notFlowControlledFrame);
41 };
42 expect(flow.read()).to.equal(notFlowControlledFrame);
44 flow._window = 0;
45 flow._queue.push({ type: 'DATA', flags: {}, data: { length: 1 } });
46 expect(flow.read()).to.equal(null);
48 expect(sendCalled).to.equal(1);
49 });
50 it('has to be overridden by the child class, otherwise it throws', function() {
51 expect(flow._send.bind(flow)).to.throw(Error);
52 });
53 });
54 describe('._increaseWindow(size) method', function() {
55 it('should increase `this._window` by `size`', function() {
56 flow._send = util.noop;
57 flow._window = 0;
59 var increase1 = util.random(0,100);
60 var increase2 = util.random(0,100);
61 flow._increaseWindow(increase1);
62 flow._increaseWindow(increase2);
63 expect(flow._window).to.equal(increase1 + increase2);
65 flow._increaseWindow(Infinity);
66 expect(flow._window).to.equal(Infinity);
67 });
68 it('should emit error when increasing with a finite `size` when `_window` is infinite', function() {
69 flow._send = util.noop;
70 flow._increaseWindow(Infinity);
71 var increase = util.random(1,100);
73 expect(flow._increaseWindow.bind(flow, increase)).to.throw('Uncaught, unspecified "error" event.');
74 });
75 it('should emit error when `_window` grows over the window limit', function() {
76 var WINDOW_SIZE_LIMIT = Math.pow(2, 31) - 1;
77 flow._send = util.noop;
78 flow._window = 0;
80 flow._increaseWindow(WINDOW_SIZE_LIMIT);
81 expect(flow._increaseWindow.bind(flow, 1)).to.throw('Uncaught, unspecified "error" event.');
83 });
84 });
85 describe('.read() method', function() {
86 describe('when the flow control queue is not empty', function() {
87 it('should return the first item in the queue if the window is enough', function() {
88 var priorityFrame = { type: 'PRIORITY', flags: {}, priority: 1 };
89 var dataFrame = { type: 'DATA', flags: {}, data: { length: 10 } };
90 flow._send = util.noop;
91 flow._window = 10;
92 flow._queue = [priorityFrame, dataFrame];
94 expect(flow.read()).to.equal(priorityFrame);
95 expect(flow.read()).to.equal(dataFrame);
96 });
97 it('should also split DATA frames when needed', function() {
98 var buffer = new Buffer(10);
99 var dataFrame = { type: 'DATA', flags: {}, stream: util.random(0, 100), data: buffer };
100 flow._send = util.noop;
101 flow._window = 5;
102 flow._queue = [dataFrame];
104 var expectedFragment = { flags: {}, type: 'DATA', stream: dataFrame.stream, data: buffer.slice(0,5) };
105 expect(flow.read()).to.deep.equal(expectedFragment);
106 expect(dataFrame.data).to.deep.equal(buffer.slice(5));
107 });
108 });
109 });
110 describe('.push(frame) method', function() {
111 it('should push `frame` into the output queue or the flow control queue', function() {
112 var priorityFrame = { type: 'PRIORITY', flags: {}, priority: 1 };
113 var dataFrame = { type: 'DATA', flags: {}, data: { length: 10 } };
114 flow._window = 10;
116 flow.push(dataFrame); // output queue
117 flow.push(dataFrame); // flow control queue, because of depleted window
118 flow.push(priorityFrame); // flow control queue, because it's not empty
120 expect(flow.read()).to.be.equal(dataFrame);
121 expect(flow._queue[0]).to.be.equal(dataFrame);
122 expect(flow._queue[1]).to.be.equal(priorityFrame);
123 });
124 });
125 describe('.write() method', function() {
126 it('call with a DATA frame should trigger sending WINDOW_UPDATE if remote flow control is not' +
127 'disabled', function(done) {
128 flow._window = 100;
129 flow._send = util.noop;
130 flow._receive = function(frame, callback) {
131 callback();
132 };
134 var buffer = new Buffer(util.random(10, 100));
135 flow.write({ type: 'DATA', flags: {}, data: buffer });
136 flow.once('readable', function() {
137 expect(flow.read()).to.be.deep.equal({
138 type: 'WINDOW_UPDATE',
139 flags: {},
140 stream: flow._flowControlId,
141 window_size: buffer.length
142 });
143 done();
144 });
145 });
146 });
147 });
148 describe('test scenario', function() {
149 var flow1, flow2;
150 beforeEach(function() {
151 flow1 = createFlow({ flow: 1 });
152 flow2 = createFlow({ flow: 2 });
153 flow1._flowControlId = flow2._flowControlId;
154 flow1._send = flow2._send = util.noop;
155 flow1._receive = flow2._receive = function(frame, callback) { callback(); };
156 });
158 describe('sending a large data stream', function() {
159 it('should work as expected', function(done) {
160 // Sender side
161 var frameNumber = util.random(5, 8);
162 var input = [];
163 flow1._send = function _send() {
164 if (input.length >= frameNumber) {
165 this.push({ type: 'DATA', flags: { END_STREAM: true }, data: new Buffer(0) });
166 this.push(null);
167 } else {
168 var buffer = new Buffer(util.random(1000, 100000));
169 input.push(buffer);
170 this.push({ type: 'DATA', flags: {}, data: buffer });
171 }
172 };
174 // Receiver side
175 var output = [];
176 flow2._receive = function _receive(frame, callback) {
177 if (frame.type === 'DATA') {
178 output.push(frame.data);
179 }
180 if (frame.flags.END_STREAM) {
181 this.emit('end_stream');
182 }
183 callback();
184 };
186 // Checking results
187 flow2.on('end_stream', function() {
188 input = util.concat(input);
189 output = util.concat(output);
191 expect(input).to.deep.equal(output);
193 done();
194 });
196 // Start piping
197 flow1.pipe(flow2).pipe(flow1);
198 });
199 });
200 });
201 });