1 | 'use strict';
|
2 |
|
3 | Object.defineProperty(exports, '__esModule', {
|
4 | value: true
|
5 | });
|
6 | exports.default = void 0;
|
7 |
|
8 | var _FifoQueue = _interopRequireDefault(require('./FifoQueue'));
|
9 |
|
10 | var _types = require('./types');
|
11 |
|
12 | function _interopRequireDefault(obj) {
|
13 | return obj && obj.__esModule ? obj : {default: obj};
|
14 | }
|
15 |
|
16 |
|
17 |
|
18 |
|
19 |
|
20 |
|
21 |
|
22 | class Farm {
|
23 | _computeWorkerKey;
|
24 | _workerSchedulingPolicy;
|
25 | _cacheKeys = Object.create(null);
|
26 | _locks = [];
|
27 | _offset = 0;
|
28 | _taskQueue;
|
29 |
|
30 | constructor(_numOfWorkers, _callback, options = {}) {
|
31 | this._numOfWorkers = _numOfWorkers;
|
32 | this._callback = _callback;
|
33 | this._computeWorkerKey = options.computeWorkerKey;
|
34 | this._workerSchedulingPolicy =
|
35 | options.workerSchedulingPolicy ?? 'round-robin';
|
36 | this._taskQueue = options.taskQueue ?? new _FifoQueue.default();
|
37 | }
|
38 |
|
39 | doWork(method, ...args) {
|
40 | const customMessageListeners = new Set();
|
41 |
|
42 | const addCustomMessageListener = listener => {
|
43 | customMessageListeners.add(listener);
|
44 | return () => {
|
45 | customMessageListeners.delete(listener);
|
46 | };
|
47 | };
|
48 |
|
49 | const onCustomMessage = message => {
|
50 | customMessageListeners.forEach(listener => listener(message));
|
51 | };
|
52 |
|
53 | const promise = new Promise(
|
54 |
|
55 |
|
56 | ((args, resolve, reject) => {
|
57 | const computeWorkerKey = this._computeWorkerKey;
|
58 | const request = [_types.CHILD_MESSAGE_CALL, false, method, args];
|
59 | let worker = null;
|
60 | let hash = null;
|
61 |
|
62 | if (computeWorkerKey) {
|
63 | hash = computeWorkerKey.call(this, method, ...args);
|
64 | worker = hash == null ? null : this._cacheKeys[hash];
|
65 | }
|
66 |
|
67 | const onStart = worker => {
|
68 | if (hash != null) {
|
69 | this._cacheKeys[hash] = worker;
|
70 | }
|
71 | };
|
72 |
|
73 | const onEnd = (error, result) => {
|
74 | customMessageListeners.clear();
|
75 |
|
76 | if (error) {
|
77 | reject(error);
|
78 | } else {
|
79 | resolve(result);
|
80 | }
|
81 | };
|
82 |
|
83 | const task = {
|
84 | onCustomMessage,
|
85 | onEnd,
|
86 | onStart,
|
87 | request
|
88 | };
|
89 |
|
90 | if (worker) {
|
91 | this._taskQueue.enqueue(task, worker.getWorkerId());
|
92 |
|
93 | this._process(worker.getWorkerId());
|
94 | } else {
|
95 | this._push(task);
|
96 | }
|
97 | }).bind(null, args)
|
98 | );
|
99 | promise.UNSTABLE_onCustomMessage = addCustomMessageListener;
|
100 | return promise;
|
101 | }
|
102 |
|
103 | _process(workerId) {
|
104 | if (this._isLocked(workerId)) {
|
105 | return this;
|
106 | }
|
107 |
|
108 | const task = this._taskQueue.dequeue(workerId);
|
109 |
|
110 | if (!task) {
|
111 | return this;
|
112 | }
|
113 |
|
114 | if (task.request[1]) {
|
115 | throw new Error('Queue implementation returned processed task');
|
116 | }
|
117 |
|
118 |
|
119 |
|
120 | let taskOnEnd = task.onEnd;
|
121 |
|
122 | const onEnd = (error, result) => {
|
123 | if (taskOnEnd) {
|
124 | taskOnEnd(error, result);
|
125 | }
|
126 |
|
127 | taskOnEnd = null;
|
128 |
|
129 | this._unlock(workerId);
|
130 |
|
131 | this._process(workerId);
|
132 | };
|
133 |
|
134 | task.request[1] = true;
|
135 |
|
136 | this._lock(workerId);
|
137 |
|
138 | this._callback(
|
139 | workerId,
|
140 | task.request,
|
141 | task.onStart,
|
142 | onEnd,
|
143 | task.onCustomMessage
|
144 | );
|
145 |
|
146 | return this;
|
147 | }
|
148 |
|
149 | _push(task) {
|
150 | this._taskQueue.enqueue(task);
|
151 |
|
152 | const offset = this._getNextWorkerOffset();
|
153 |
|
154 | for (let i = 0; i < this._numOfWorkers; i++) {
|
155 | this._process((offset + i) % this._numOfWorkers);
|
156 |
|
157 | if (task.request[1]) {
|
158 | break;
|
159 | }
|
160 | }
|
161 |
|
162 | return this;
|
163 | }
|
164 |
|
165 | _getNextWorkerOffset() {
|
166 | switch (this._workerSchedulingPolicy) {
|
167 | case 'in-order':
|
168 | return 0;
|
169 |
|
170 | case 'round-robin':
|
171 | return this._offset++;
|
172 | }
|
173 | }
|
174 |
|
175 | _lock(workerId) {
|
176 | this._locks[workerId] = true;
|
177 | }
|
178 |
|
179 | _unlock(workerId) {
|
180 | this._locks[workerId] = false;
|
181 | }
|
182 |
|
183 | _isLocked(workerId) {
|
184 | return this._locks[workerId];
|
185 | }
|
186 | }
|
187 |
|
188 | exports.default = Farm;
|