Add hosted synthetic control plane

apps/web/app/api/admin/synthetic/shared.ts

@@ -0,0 +1,63 @@
+const jsonResponse = (body: unknown, status = 200): Response => {
+  return new Response(JSON.stringify(body), {
+    status,
+    headers: {
+      "content-type": "application/json"
+    }
+  });
+};
+
+export const isSyntheticAdminFeatureEnabled = (
+  value = process.env.NEXT_PUBLIC_SYNTHETIC_ADMIN
+): boolean => value === "1";
+
+export const getSyntheticAdminProxyConfig = (
+  env: Record<string, string | undefined> = process.env
+): { apiBaseUrl: string; token: string } | null => {
+  const apiBaseUrl = env.NEXT_PUBLIC_API_URL?.trim();
+  const token = env.SYNTHETIC_ADMIN_TOKEN?.trim();
+  if (!apiBaseUrl || !token) {
+    return null;
+  }
+  return { apiBaseUrl, token };
+};
+
+export const proxySyntheticAdminRequest = async (
+  path: string,
+  init: RequestInit = {},
+  env: Record<string, string | undefined> = process.env
+): Promise<Response> => {
+  if (!isSyntheticAdminFeatureEnabled(env.NEXT_PUBLIC_SYNTHETIC_ADMIN)) {
+    return jsonResponse({ error: "not found" }, 404);
+  }
+
+  const config = getSyntheticAdminProxyConfig(env);
+  if (!config) {
+    return jsonResponse(
+      {
+        error: "synthetic admin proxy misconfigured"
+      },
+      500
+    );
+  }
+
+  const url = new URL(path, config.apiBaseUrl);
+  const headers = new Headers(init.headers);
+  headers.set("authorization", `Bearer ${config.token}`);
+  if (!headers.has("content-type") && init.body) {
+    headers.set("content-type", "application/json");
+  }
+
+  const response = await fetch(url.toString(), {
+    ...init,
+    cache: "no-store",
+    headers
+  });
+
+  return new Response(response.body, {
+    status: response.status,
+    headers: {
+      "content-type": response.headers.get("content-type") ?? "application/json"
+    }
+  });
+};