Add --disable-proxy option (#6349)

src/node/http.ts

@@ -75,6 +75,25 @@ export const replaceTemplates = <T extends object>(
     .replace("{{OPTIONS}}", () => escapeJSON(serverOptions))
 }
 
+/**
+ * Throw an error if proxy is not enabled. Call `next` if provided.
+ */
+export const ensureProxyEnabled = (req: express.Request, _?: express.Response, next?: express.NextFunction): void => {
+  if (!proxyEnabled(req)) {
+    throw new HttpError("Forbidden", HttpCode.Forbidden)
+  }
+  if (next) {
+    next()
+  }
+}
+
+/**
+ * Return true if proxy is enabled.
+ */
+export const proxyEnabled = (req: express.Request): boolean => {
+  return !req.args["disable-proxy"]
+}
+
 /**
  * Throw an error if not authorized. Call `next` if provided.
  */