forked from felicienfrancois/node-electron-proxy-agent
-
Notifications
You must be signed in to change notification settings - Fork 10
/
agent.ts
261 lines (229 loc) · 7.6 KB
/
agent.ts
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
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
import http from 'http';
import https from 'https';
import net from 'net';
import createDebug from 'debug';
import { Readable, Duplex } from 'stream';
import { format } from 'url';
import { HttpProxyAgent, HttpProxyAgentOptions } from 'http-proxy-agent';
import { HttpsProxyAgent, HttpsProxyAgentOptions } from 'https-proxy-agent';
import { SocksProxyAgent, SocksProxyAgentOptions } from 'socks-proxy-agent';
import {
Agent,
AgentConnectOpts,
} from 'agent-base';
import EventEmitter from 'events';
const debug = createDebug('pac-proxy-agent');
type FindProxyForURL = (req: http.ClientRequest, opts: http.RequestOptions, url: string) => Promise<string | undefined>;
/**
* The `PacProxyAgent` class.
*
* A few different "protocol" modes are supported (supported protocols are
* backed by the `get-uri` module):
*
* - "pac+data", "data" - refers to an embedded "data:" URI
* - "pac+file", "file" - refers to a local file
* - "pac+ftp", "ftp" - refers to a file located on an FTP server
* - "pac+http", "http" - refers to an HTTP endpoint
* - "pac+https", "https" - refers to an HTTPS endpoint
*
* @api public
*/
class _PacProxyAgent extends Agent {
resolver: FindProxyForURL;
opts: createPacProxyAgent.PacProxyAgentOptions;
cache?: Readable;
constructor(resolver: FindProxyForURL, opts: createPacProxyAgent.PacProxyAgentOptions = {}) {
super(opts);
debug('Creating PacProxyAgent with options %o', opts);
this.resolver = resolver;
this.opts = { ...opts };
this.cache = undefined;
}
/**
* Called when the node-core HTTP client library is creating a new HTTP request.
*
* @api protected
*/
async connect(req: http.ClientRequest, opts: AgentConnectOpts): Promise<Duplex | http.Agent> {
const { secureEndpoint } = opts;
// Calculate the `url` parameter
const defaultPort = secureEndpoint ? 443 : 80;
let path = req.path;
let search: string | null = null;
const firstQuestion = path.indexOf('?');
if (firstQuestion !== -1) {
search = path.substring(firstQuestion);
path = path.substring(0, firstQuestion);
}
const urlOpts = {
...opts,
protocol: secureEndpoint ? 'https:' : 'http:',
pathname: path,
search,
// need to use `hostname` instead of `host` otherwise `port` is ignored
hostname: opts.host,
host: null,
href: null,
// set `port` to null when it is the protocol default port (80 / 443)
port: defaultPort === opts.port ? null : opts.port
};
const url = format(urlOpts);
debug('url: %o', url);
let result = await this.resolver(req, opts, url);
// Default to "DIRECT" if a falsey value was returned (or nothing)
if (!result) {
result = 'DIRECT';
}
const proxies = String(result)
.trim()
.split(/\s*;\s*/g)
.filter(Boolean);
if (this.opts.fallbackToDirect && !proxies.includes('DIRECT')) {
proxies.push('DIRECT');
}
for (const proxy of proxies) {
let agent: http.Agent | null = null;
const [type, target] = proxy.split(/\s+/);
debug('Attempting to use proxy: %o', proxy);
if (type === 'DIRECT') {
// Needed for SNI.
const originalAgent = this.opts.originalAgent;
const defaultAgent = secureEndpoint ? https.globalAgent : http.globalAgent;
agent = originalAgent === false ? new (defaultAgent as any).constructor() : (originalAgent || defaultAgent)
} else if (type === 'SOCKS' || type === 'SOCKS5') {
// Use a SOCKSv5h proxy
agent = new SocksProxyAgent(`socks://${target}`);
} else if (type === 'SOCKS4') {
// Use a SOCKSv4a proxy
agent = new SocksProxyAgent(`socks4a://${target}`);
} else if (
type === 'PROXY' ||
type === 'HTTP' ||
type === 'HTTPS'
) {
// Use an HTTP or HTTPS proxy
// http://dev.chromium.org/developers/design-documents/secure-web-proxy
const proxyURL = `${
type === 'HTTPS' ? 'https' : 'http'
}://${target}`;
if (secureEndpoint) {
agent = new HttpsProxyAgent2(proxyURL, this.opts);
} else {
agent = new HttpProxyAgent(proxyURL, this.opts);
}
}
try {
if (agent) {
let s: Duplex | http.Agent;
if (agent instanceof Agent) {
s = await agent.connect(req, opts);
} else {
s = agent;
}
req.emit('proxy', { proxy, socket: s });
return s;
}
throw new Error(`Could not determine proxy type for: ${proxy}`);
} catch (err) {
debug('Got error for proxy %o: %o', proxy, err);
req.emit('proxy', { proxy, error: err });
}
}
throw new Error(
`Failed to establish a socket connection to proxies: ${JSON.stringify(
proxies
)}`
);
}
}
type LookupProxyAuthorization = (proxyURL: string, proxyAuthenticate: string | string[] | undefined, state: Record<string, any>) => Promise<string | undefined>;
type HttpsProxyAgentOptions2<Uri> = HttpsProxyAgentOptions<Uri> & { lookupProxyAuthorization?: LookupProxyAuthorization };
interface ConnectResponse {
statusCode: number;
statusText: string;
headers: http.IncomingHttpHeaders;
}
class HttpsProxyAgent2<Uri extends string> extends HttpsProxyAgent<Uri> {
addHeaders: http.OutgoingHttpHeaders;
lookupProxyAuthorization?: LookupProxyAuthorization;
constructor(proxy: Uri | URL, opts: HttpsProxyAgentOptions2<Uri>) {
const addHeaders = {};
const origHeaders = opts?.headers;
const agentOpts: HttpsProxyAgentOptions<Uri> = {
...opts,
headers: (): http.OutgoingHttpHeaders => {
const headers = origHeaders
? typeof origHeaders === 'function'
? origHeaders()
: origHeaders
: {};
return {
...headers,
...addHeaders
};
}
};
super(proxy, agentOpts);
this.addHeaders = addHeaders;
this.lookupProxyAuthorization = opts.lookupProxyAuthorization;
}
async connect(req: http.ClientRequest, opts: AgentConnectOpts, state: Record<string, any> = {}): Promise<net.Socket> {
const tmpReq = new EventEmitter();
let connect: ConnectResponse | undefined;
tmpReq.once('proxyConnect', (_connect: ConnectResponse) => {
connect = _connect;
});
if (this.lookupProxyAuthorization && !this.addHeaders['Proxy-Authorization']) {
try {
const proxyAuthorization = await this.lookupProxyAuthorization(this.proxy.href, undefined, state);
if (proxyAuthorization) {
this.addHeaders['Proxy-Authorization'] = proxyAuthorization;
}
} catch (err) {
req.emit('error', err);
}
}
const s = await super.connect(tmpReq as any, opts);
const proxyAuthenticate = connect?.headers['proxy-authenticate'] as string | string[] | undefined;
if (this.lookupProxyAuthorization && connect?.statusCode === 407 && proxyAuthenticate) {
try {
const proxyAuthorization = await this.lookupProxyAuthorization(this.proxy.href, proxyAuthenticate, state);
if (proxyAuthorization) {
this.addHeaders['Proxy-Authorization'] = proxyAuthorization;
tmpReq.removeAllListeners();
s.destroy();
return this.connect(req, opts, state);
}
} catch (err) {
req.emit('error', err);
}
}
req.once('socket', s => tmpReq.emit('socket', s));
return s;
}
}
function createPacProxyAgent(
resolver: FindProxyForURL,
opts?: createPacProxyAgent.PacProxyAgentOptions
): _PacProxyAgent {
if (!opts) {
opts = {};
}
if (typeof resolver !== 'function') {
throw new TypeError('a resolve function must be specified!');
}
return new _PacProxyAgent(resolver, opts);
}
namespace createPacProxyAgent {
export type PacProxyAgentOptions =
HttpProxyAgentOptions<''> &
HttpsProxyAgentOptions2<''> &
SocksProxyAgentOptions & {
fallbackToDirect?: boolean;
originalAgent?: false | http.Agent;
}
export type PacProxyAgent = _PacProxyAgent;
export const PacProxyAgent = _PacProxyAgent;
createPacProxyAgent.prototype = _PacProxyAgent.prototype;
}
export = createPacProxyAgent;