import { Server } from "proxy-chain";
/**
* Stores the active proxy server instance.
* We keep track of it to ensure we can shut it down properly.
*/
let bridgeServer: Server | null = null;
/**
* Starts a local HTTP proxy bridge that forwards traffic to an upstream proxy.
* This is used to work around Chromium's limitation with SOCKS5 authentication.
*
* @param upstreamProxyUrl - The full upstream proxy URL (e.g. "socks5://user:pass@host:port")
* @returns The URL of the local bridge server (e.g. "http://127.0.0.1:12345")
*/
export async function startProxyBridge(upstreamProxyUrl: string): Promise<string> {
// If a bridge is already running, close it first to avoid leaks
if (bridgeServer) {
await stopProxyBridge();
}
try {
console.debug(`Starting proxy bridge for upstream: ${upstreamProxyUrl}`);
bridgeServer = new Server({
// 0 lets the OS assign a random available port
port: 0,
host: "127.0.0.1",
// We turned off verbose logging to keep stdout clean, unless debugging is needed
verbose: false,
prepareRequestFunction: () => {
return {
upstreamProxyUrl,
};
},
});
await bridgeServer.listen();
// We use 127.0.0.1 explicitly to avoid issues with some environments resolving 'localhost'
const port = bridgeServer.port;
const localBridgeUrl = `http://127.0.0.1:${port}`;
console.debug(`Proxy bridge started at: ${localBridgeUrl}`);
return localBridgeUrl;
} catch (error) {
console.error("Failed to start proxy bridge:", error);
throw new Error(`Failed to start proxy bridge: ${(error as Error).message}`);
}
}
/**
* Stops the local proxy bridge if it is running.
* Should be called when the browser session ends.
*/
export async function stopProxyBridge(): Promise<void> {
if (bridgeServer) {
try {
await bridgeServer.close(true); // true = force close connections
console.debug("Proxy bridge stopped successfully");
} catch (error) {
console.warn("Error stopping proxy bridge:", error);
} finally {
bridgeServer = null;
}
}
}
