Document and test production CORS allowlist

Docs/vercel-deploy.md

@@ -28,9 +28,14 @@ ZCore uses two Vercel projects in this monorepo.
 - `DATABASE_URL` — managed MySQL (#15)
 - `ADMIN_SECRET` — strong random secret
 - `STELLAR_NETWORK=testnet`
+- `CORS_ORIGINS=https://dapp-zcore.vercel.app,https://zcore-xi.vercel.app`
 - `SCORE_REGISTRY_CONTRACT_ID` — optional (#16)
 - `ORACLE_SECRET_KEY` — optional
 
+`CORS_ORIGINS` is a comma-separated allowlist of browser origins that may call
+the API with credentials. Keep `http://localhost:3001` in local `.env` files,
+and set only production dapp or partner origins in Vercel.
+
 ## Manual deploy (fallback)
 
 ```bash

Server/src/config/__tests__/cors.config.test.ts

@@ -1,14 +1,85 @@
 import { describe, expect, it } from "vitest";
-import { parseAllowedOrigins } from "../../config/cors.config";
+import { getCorsOptions, parseAllowedOrigins } from "../../config/cors.config";
 
 describe("cors.config", () => {
   it("parses comma-separated origins", () => {
     process.env.CORS_ORIGINS = "https://a.com, https://b.com";
     expect(parseAllowedOrigins()).toEqual(["https://a.com", "https://b.com"]);
   });
 
+  it("trims configured origins and ignores empty entries", () => {
+    process.env.CORS_ORIGINS = " https://dapp-zcore.vercel.app, ,https://zcore-xi.vercel.app ";
+    expect(parseAllowedOrigins()).toEqual([
+      "https://dapp-zcore.vercel.app",
+      "https://zcore-xi.vercel.app",
+    ]);
+  });
+
   it("defaults to local dapp origin", () => {
     delete process.env.CORS_ORIGINS;
     expect(parseAllowedOrigins()).toContain("http://localhost:3001");
   });
+
+  it("allows configured browser origins", () =>
+    new Promise<void>((resolve, reject) => {
+      process.env.CORS_ORIGINS = "https://dapp-zcore.vercel.app";
+      const options = getCorsOptions();
+
+      if (typeof options.origin !== "function") {
+        reject(new Error("Expected function origin option"));
+        return;
+      }
+
+      options.origin("https://dapp-zcore.vercel.app", (error, allowed) => {
+        try {
+          expect(error).toBeNull();
+          expect(allowed).toBe(true);
+          resolve();
+        } catch (assertionError) {
+          reject(assertionError);
+        }
+      });
+    }));
+
+  it("rejects browser origins outside the allowlist", () =>
+    new Promise<void>((resolve, reject) => {
+      process.env.CORS_ORIGINS = "https://dapp-zcore.vercel.app";
+      const options = getCorsOptions();
+
+      if (typeof options.origin !== "function") {
+        reject(new Error("Expected function origin option"));
+        return;
+      }
+
+      options.origin("https://evil.example", (error) => {
+        try {
+          expect(error).toBeInstanceOf(Error);
+          expect(error?.message).toBe("Origin https://evil.example not allowed by CORS");
+          resolve();
+        } catch (assertionError) {
+          reject(assertionError);
+        }
+      });
+    }));
+
+  it("allows server-to-server calls without an Origin header", () =>
+    new Promise<void>((resolve, reject) => {
+      process.env.CORS_ORIGINS = "https://dapp-zcore.vercel.app";
+      const options = getCorsOptions();
+
+      if (typeof options.origin !== "function") {
+        reject(new Error("Expected function origin option"));
+        return;
+      }
+
+      options.origin(undefined, (error, allowed) => {
+        try {
+          expect(error).toBeNull();
+          expect(allowed).toBe(true);
+          resolve();
+        } catch (assertionError) {
+          reject(assertionError);
+        }
+      });
+    }));
 });