Refactors model provider logic and updates dependencies

Author: KevyVo

samples/mastra-nextjs/.defang/lab

@@ -41,3 +41,5 @@ yarn-error.log*
 next-env.d.ts
 
 .mastra
+../.defang
+

samples/mastra-nextjs/app/.gitignore

@@ -11,8 +11,8 @@
   },
   "dependencies": {
     "@ai-sdk/amazon-bedrock": "^3.0.67",
-    "@ai-sdk/google": "^2.0.44",
     "@ai-sdk/google-vertex": "^3.0.86",
+    "@ai-sdk/provider": "^2.0.0",
     "@assistant-ui/react": "^0.11.39",
     "@assistant-ui/react-ai-sdk": "^1.1.11",
     "@assistant-ui/react-markdown": "^0.11.4",

samples/mastra-nextjs/app/package.json

@@ -1,5 +1,6 @@
 import { Agent } from "@mastra/core/agent";
 import { createAmazonBedrock } from "@ai-sdk/amazon-bedrock";
+import type { LanguageModelV2 } from "@ai-sdk/provider";
 import { fromNodeProviderChain } from "@aws-sdk/credential-providers";
 import { createVertex } from "@ai-sdk/google-vertex";
 
@@ -12,27 +13,56 @@ import { getRepositoryCommits } from "../tools/getRepositoryCommits";
 import { getRepositoryPullRequests } from "../tools/getRepositoryPullRequests";
 import { getRepositoryStars } from "../tools/getRepositoryStars";
 
-function AWSModelProvider(modelName: string) {
+// https://ai-sdk.dev/providers/ai-sdk-providers/amazon-bedrock#using-aws-sdk-credentials-chain-instance-profiles-instance-roles-ecs-roles-eks-service-accounts-etc
+function createAWSModelProvider(modelName: string): LanguageModelV2 {
   return createAmazonBedrock({
     credentialProvider: fromNodeProviderChain(),
   })(modelName);
 }
 
-function GCPModelProvider(model: string) {
+// https://ai-sdk.dev/providers/ai-sdk-providers/google-vertex
+function createGCPModelProvider(modelName: string): LanguageModelV2 {
+  const projectId = process.env.DEFANG_GCP_PROJECT;
+  if (projectId === undefined) {
+    throw new Error(
+      "DEFANG_GCP_PROJECT is not defined in environment variables"
+    );
+  }
+  const location = process.env.DEFANG_GCP_LOCATION;
+  if (location === undefined) {
+    throw new Error(
+      "DEFANG_GCP_LOCATION is not defined in environment variables"
+    );
+  }
   return createVertex({
-    project: "cloudbuildtest-468719",
-    location: "us-central1",
-  })(model);
+    project: projectId,
+    location: location,
+  })(modelName);
+}
+
+function getModel(): LanguageModelV2 {
+  const provider = process.env.DEFANG_PROVIDER;
+  const modelName = process.env.LLM_MODEL;
+  if (modelName === undefined) {
+    throw new Error("LLM_MODEL is not defined in environment variables");
+  }
+
+  if (provider === "aws") {
+    return createAWSModelProvider(modelName);
+  }
+
+  if (provider === "gcp") {
+    return createGCPModelProvider(modelName);
+  }
+
+  throw new Error(`Unsupported DEFANG_PROVIDER: ${provider}`);
 }
 
 export const agent = new Agent({
   name: "agent",
   instructions,
   memory: getMemory,
-  model:
-    process.env.DEFANG_PROVIDER === "aws"
-      ? AWSModelProvider(process.env.LLM_MODEL || "us.amazon.nova-lite-v1:0")
-      : GCPModelProvider(process.env.LLM_MODEL || "gemini-2.5-pro"),
+  model: getModel,
   tools: {
     getFilePaths,
     getFileContent,

samples/mastra-nextjs/app/pnpm-lock.yaml

@@ -7,9 +7,11 @@ services:
     environment:
       - DB_URL=postgres://postgres:${POSTGRES_PASSWORD}@database:5432/postgres
       - DB_SSL=true #set this to false if deploying to defang playground
-      - GITHUB_TOKEN
-      - DEFANG_PROVIDER=gcp
-      - LLM_MODEL=gemini-2.5-flash #anthropic.claude-3-5-sonnet-20241022-v2:0
+      - GITHUB_TOKEN #optional, remove this line if unused
+      - DEFANG_PROVIDER=aws # change to gcp when deploying to Google Cloud
+      - DEFANG_GCP_PROJECT # change to your GCP project when deploying to Google Cloud
+      - DEFANG_GCP_LOCATION #should be us-central1 when deploying to Google Cloud, else change to your perferred location
+      - LLM_MODEL=anthropic.claude-3-5-sonnet-20241022-v2:0 #gemini-2.5-flash for GCP, anthroipc.claude-3-5-sonnet-20241022-v2 for AWS
     restart: unless-stopped
     ports:
       - mode: ingress