makes gatekeeper compatible with sillytavern claude impl

src/proxy/auth/gatekeeper.ts

@@ -1,4 +1,4 @@
-import type { RequestHandler } from "express";
+import type { Request, RequestHandler } from "express";
 import { config } from "../../config";
 import { authenticate, getUser } from "./user-store";
 
@@ -6,9 +6,29 @@ const GATEKEEPER = config.gatekeeper;
 const PROXY_KEY = config.proxyKey;
 const ADMIN_KEY = config.adminKey;
 
+function getProxyAuthorizationFromRequest(req: Request): string | undefined {
+  // Anthropic's API uses x-api-key instead of Authorization.  Some clients will
+  // pass the _proxy_ key in this header too, instead of providing it as a
+  // Bearer token in the Authorization header.  So we need to check both.
+  // Prefer the Authorization header if both are present.
+
+  if (req.headers.authorization) {
+    const token = req.headers.authorization?.slice("Bearer ".length);
+    delete req.headers.authorization;
+    return token;
+  }
+
+  if (req.headers["x-api-key"]) {
+    const token = req.headers["x-api-key"]?.toString();
+    delete req.headers["x-api-key"];
+    return token;
+  }
+
+  return undefined;
+}
+
 export const gatekeeper: RequestHandler = (req, res, next) => {
-  const token = req.headers.authorization?.slice("Bearer ".length);
-  delete req.headers.authorization;
+  const token = getProxyAuthorizationFromRequest(req);
 
   // TODO: Generate anonymous users based on IP address for public or proxy_key
   // modes so that all middleware can assume a user of some sort is present.