forked from sindresorhus/get-port
/
index.js
155 lines (125 loc) · 3.61 KB
/
index.js
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
'use strict';
const net = require('net');
const os = require('os');
class Locked extends Error {
constructor(port) {
super(`${port} is locked`);
}
}
const lockedPorts = {
old: new Set(),
young: new Set()
};
// On this interval, the old locked ports are discarded,
// the young locked ports are moved to old locked ports,
// and a new young set for locked ports are created.
const releaseOldLockedPortsIntervalMs = 1000 * 15;
// Lazily create interval on first use
let interval;
const getHosts = () => {
const interfaces = os.networkInterfaces();
const results = [];
for (const _interface of Object.values(interfaces)) {
for (const config of _interface) {
results.push(config.address);
}
}
// Add undefined value for createServer function to use default host,
// and default IPv4 host in case createServer defaults to IPv6.
return results.concat(undefined, '0.0.0.0');
};
const checkAvailablePort = options =>
new Promise((resolve, reject) => {
const server = net.createServer();
server.unref();
server.on('error', reject);
server.listen(options, () => {
const {port} = server.address();
server.close(() => {
resolve(port);
});
});
});
const getAvailablePort = async (options, hosts) => {
if (options.host || options.port === 0) {
return checkAvailablePort(options);
}
let index = 0;
const hostsCopy = [...hosts];
while (index < hostsCopy.length) {
const host = hostsCopy[index];
try {
await checkAvailablePort({port: options.port, host}); // eslint-disable-line no-await-in-loop
} catch (error) {
if (['EADDRNOTAVAIL', 'EINVAL'].includes(error.code)) {
hostsCopy.splice(hostsCopy.indexOf(host), 1);
continue;
} else {
throw error;
}
}
++index;
}
return options.port;
};
const portCheckSequence = function * (ports) {
if (ports) {
yield * ports;
}
yield 0; // Fall back to 0 if anything else failed
};
module.exports = async options => {
let ports;
if (options) {
ports = typeof options.port === 'number' ? [options.port] : options.port;
}
if (interval === undefined) {
interval = setInterval(() => {
lockedPorts.old = lockedPorts.young;
lockedPorts.young = new Set();
}, releaseOldLockedPortsIntervalMs);
// Does not exist in some environments (Electron, Jest jsdom env, browser, etc).
if (interval.unref) {
interval.unref();
}
}
const hosts = getHosts();
for (const port of portCheckSequence(ports)) {
try {
let availablePort = await getAvailablePort({...options, port}, hosts); // eslint-disable-line no-await-in-loop
while (lockedPorts.old.has(availablePort) || lockedPorts.young.has(availablePort)) {
if (port !== 0) {
throw new Locked(port);
}
availablePort = await getAvailablePort({...options, port}, hosts); // eslint-disable-line no-await-in-loop
}
lockedPorts.young.add(availablePort);
return availablePort;
} catch (error) {
if (!['EADDRINUSE', 'EACCES'].includes(error.code) && !(error instanceof Locked)) {
throw error;
}
}
}
throw new Error('No available ports found');
};
module.exports.makeRange = (from, to) => {
if (!Number.isInteger(from) || !Number.isInteger(to)) {
throw new TypeError('`from` and `to` must be integer numbers');
}
if (from < 1024 || from > 65535) {
throw new RangeError('`from` must be between 1024 and 65535');
}
if (to < 1024 || to > 65536) {
throw new RangeError('`to` must be between 1024 and 65536');
}
if (to < from) {
throw new RangeError('`to` must be greater than or equal to `from`');
}
const generator = function * (from, to) {
for (let port = from; port <= to; port++) {
yield port;
}
};
return generator(from, to);
};