File size: 7,127 Bytes
026255b | 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 | "use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.HttpProxyMiddleware = void 0;
const httpProxy = require("http-proxy");
const configuration_1 = require("./configuration");
const get_plugins_1 = require("./get-plugins");
const path_filter_1 = require("./path-filter");
const PathRewriter = require("./path-rewriter");
const Router = require("./router");
const debug_1 = require("./debug");
const function_1 = require("./utils/function");
const logger_1 = require("./logger");
class HttpProxyMiddleware {
constructor(options) {
this.wsInternalSubscribed = false;
this.serverOnCloseSubscribed = false;
// https://github.com/Microsoft/TypeScript/wiki/'this'-in-TypeScript#red-flags-for-this
this.middleware = (async (req, res, next) => {
if (this.shouldProxy(this.proxyOptions.pathFilter, req)) {
try {
const activeProxyOptions = await this.prepareProxyRequest(req);
(0, debug_1.Debug)(`proxy request to target: %O`, activeProxyOptions.target);
this.proxy.web(req, res, activeProxyOptions);
}
catch (err) {
next?.(err);
}
}
else {
next?.();
}
/**
* Get the server object to subscribe to server events;
* 'upgrade' for websocket and 'close' for graceful shutdown
*
* NOTE:
* req.socket: node >= 13
* req.connection: node < 13 (Remove this when node 12/13 support is dropped)
*/
const server = (req.socket ?? req.connection)?.server;
if (server && !this.serverOnCloseSubscribed) {
server.on('close', () => {
(0, debug_1.Debug)('server close signal received: closing proxy server');
this.proxy.close();
});
this.serverOnCloseSubscribed = true;
}
if (this.proxyOptions.ws === true) {
// use initial request to access the server object to subscribe to http upgrade event
this.catchUpgradeRequest(server);
}
});
this.catchUpgradeRequest = (server) => {
if (!this.wsInternalSubscribed) {
(0, debug_1.Debug)('subscribing to server upgrade event');
server.on('upgrade', this.handleUpgrade);
// prevent duplicate upgrade handling;
// in case external upgrade is also configured
this.wsInternalSubscribed = true;
}
};
this.handleUpgrade = async (req, socket, head) => {
try {
if (this.shouldProxy(this.proxyOptions.pathFilter, req)) {
const activeProxyOptions = await this.prepareProxyRequest(req);
this.proxy.ws(req, socket, head, activeProxyOptions);
(0, debug_1.Debug)('server upgrade event received. Proxying WebSocket');
}
}
catch (err) {
// This error does not include the URL as the fourth argument as we won't
// have the URL if `this.prepareProxyRequest` throws an error.
this.proxy.emit('error', err, req, socket);
}
};
/**
* Determine whether request should be proxied.
*/
this.shouldProxy = (pathFilter, req) => {
try {
return (0, path_filter_1.matchPathFilter)(pathFilter, req.url, req);
}
catch (err) {
(0, debug_1.Debug)('Error: matchPathFilter() called with request url: ', `"${req.url}"`);
this.logger.error(err);
return false;
}
};
/**
* Apply option.router and option.pathRewrite
* Order matters:
* Router uses original path for routing;
* NOT the modified path, after it has been rewritten by pathRewrite
* @param {Object} req
* @return {Object} proxy options
*/
this.prepareProxyRequest = async (req) => {
/**
* Incorrect usage confirmed: https://github.com/expressjs/express/issues/4854#issuecomment-1066171160
* Temporary restore req.url patch for {@link src/legacy/create-proxy-middleware.ts legacyCreateProxyMiddleware()}
* FIXME: remove this patch in future release
*/
if (this.middleware.__LEGACY_HTTP_PROXY_MIDDLEWARE__) {
req.url = req.originalUrl || req.url;
}
const newProxyOptions = Object.assign({}, this.proxyOptions);
// Apply in order:
// 1. option.router
// 2. option.pathRewrite
await this.applyRouter(req, newProxyOptions);
await this.applyPathRewrite(req, this.pathRewriter);
return newProxyOptions;
};
// Modify option.target when router present.
this.applyRouter = async (req, options) => {
let newTarget;
if (options.router) {
newTarget = await Router.getTarget(req, options);
if (newTarget) {
(0, debug_1.Debug)('router new target: "%s"', newTarget);
options.target = newTarget;
}
}
};
// rewrite path
this.applyPathRewrite = async (req, pathRewriter) => {
if (pathRewriter) {
const path = await pathRewriter(req.url, req);
if (typeof path === 'string') {
(0, debug_1.Debug)('pathRewrite new path: %s', req.url);
req.url = path;
}
else {
(0, debug_1.Debug)('pathRewrite: no rewritten path found: %s', req.url);
}
}
};
(0, configuration_1.verifyConfig)(options);
this.proxyOptions = options;
this.logger = (0, logger_1.getLogger)(options);
(0, debug_1.Debug)(`create proxy server`);
this.proxy = httpProxy.createProxyServer({});
this.registerPlugins(this.proxy, this.proxyOptions);
this.pathRewriter = PathRewriter.createPathRewriter(this.proxyOptions.pathRewrite); // returns undefined when "pathRewrite" is not provided
// https://github.com/chimurai/http-proxy-middleware/issues/19
// expose function to upgrade externally
this.middleware.upgrade = (req, socket, head) => {
if (!this.wsInternalSubscribed) {
this.handleUpgrade(req, socket, head);
}
};
}
registerPlugins(proxy, options) {
const plugins = (0, get_plugins_1.getPlugins)(options);
plugins.forEach((plugin) => {
(0, debug_1.Debug)(`register plugin: "${(0, function_1.getFunctionName)(plugin)}"`);
plugin(proxy, options);
});
}
}
exports.HttpProxyMiddleware = HttpProxyMiddleware;
|