chore: make playground example fallback to WorkersAI when OpenAI key is not set (#796)

* chore: make playground example fallback to WorkersAI when OpenAI key is not set

* fix

Author: iTrooz

examples/playground/env.d.ts

@@ -1,5 +1,5 @@
 /* eslint-disable */
-// Generated by Wrangler by running `wrangler types env.d.ts --include-runtime false` (hash: f103d0d6947e92f53f1c4ba8d54acaa6)
+// Generated by Wrangler by running `wrangler types env.d.ts --include-runtime false` (hash: 58d9bb5230a737a6ca0946ef9228fa8c)
 declare namespace Cloudflare {
   interface GlobalProps {
     mainModule: typeof import("./src/server");
@@ -11,6 +11,7 @@ declare namespace Cloudflare {
     Stateful: DurableObjectNamespace<import("./src/server").Stateful>;
     Chat: DurableObjectNamespace<import("./src/server").Chat>;
     Rpc: DurableObjectNamespace<import("./src/server").Rpc>;
+    AI: Ai;
     ASSETS: Fetcher;
   }
 }

examples/playground/src/model.ts

@@ -1,3 +1,13 @@
+import { createWorkersAI } from "workers-ai-provider";
 import { openai } from "@ai-sdk/openai";
+import type { LanguageModelV3 } from "@ai-sdk/provider";
+import { env } from "cloudflare:workers";
 
-export const model = openai("gpt-4o");
+export const model: LanguageModelV3 = (() => {
+  if (env.OPENAI_API_KEY) {
+    return openai("gpt-4");
+  } else {
+    const workersai = createWorkersAI({ binding: env.AI });
+    return workersai("@cf/meta/llama-2-7b-chat-int8");
+  }
+})();

examples/playground/wrangler.jsonc

@@ -7,6 +7,10 @@
     "nodejs_compat",
     "nodejs_compat_populate_process_env"
   ],
+  "ai": {
+    "binding": "AI",
+    "remote": true
+  },
   "assets": {
     "binding": "ASSETS"
   },