Add hosted synthetic control plane

apps/web/app/api/admin/synthetic/routes.test.ts

@@ -0,0 +1,61 @@
+import { afterEach, beforeEach, describe, expect, it, mock } from "bun:test";
+import {
+  getSyntheticAdminProxyConfig,
+  isSyntheticAdminFeatureEnabled
+} from "./shared";
+
+const originalFetch = globalThis.fetch;
+
+describe("synthetic admin proxy helpers", () => {
+  beforeEach(() => {
+    process.env.NEXT_PUBLIC_SYNTHETIC_ADMIN = "1";
+    process.env.NEXT_PUBLIC_API_URL = "http://127.0.0.1:4000";
+    process.env.SYNTHETIC_ADMIN_TOKEN = "secret-token";
+  });
+
+  afterEach(() => {
+    globalThis.fetch = originalFetch;
+  });
+
+  it("gates visibility on the public env flag", () => {
+    expect(isSyntheticAdminFeatureEnabled("1")).toBe(true);
+    expect(isSyntheticAdminFeatureEnabled("0")).toBe(false);
+  });
+
+  it("reads the proxy config from server env only", () => {
+    expect(getSyntheticAdminProxyConfig()).toEqual({
+      apiBaseUrl: "http://127.0.0.1:4000",
+      token: "secret-token"
+    });
+  });
+
+  it("proxies status requests with the backend admin token", async () => {
+    const fetchMock = mock(async (input: string | URL, init?: RequestInit) => {
+      expect(String(input)).toBe("http://127.0.0.1:4000/admin/synthetic/status");
+      expect(new Headers(init?.headers).get("authorization")).toBe("Bearer secret-token");
+      return new Response(JSON.stringify({ enabled: true }), {
+        status: 200,
+        headers: {
+          "content-type": "application/json"
+        }
+      });
+    });
+    globalThis.fetch = fetchMock as typeof fetch;
+    const route = await import("./status/route");
+
+    const response = await route.GET();
+
+    expect(response.status).toBe(200);
+    expect(await response.json()).toEqual({ enabled: true });
+    expect(fetchMock).toHaveBeenCalledTimes(1);
+  });
+
+  it("returns 404 from proxy routes when the internal UI flag is off", async () => {
+    process.env.NEXT_PUBLIC_SYNTHETIC_ADMIN = "0";
+    const route = await import("./control/route");
+
+    const response = await route.GET();
+
+    expect(response.status).toBe(404);
+  });
+});