feat(genai): add migrated functionCallingStreamContent sample from generative-ai (#4367)

* feat(genai): rename and migrate functionCallingStreamContent sample

* fix(genai): update function response

* fix: update region tag

Author: angelcaamal

genai/tools/test/tools-func-calling-stream-content.test.js

@@ -0,0 +1,43 @@
+// Copyright 2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+'use strict';
+
+const {assert} = require('chai');
+const {describe, it} = require('mocha');
+const cp = require('child_process');
+const execSync = cmd => cp.execSync(cmd, {encoding: 'utf-8'});
+
+const projectId = process.env.GOOGLE_CLOUD_PROJECT;
+const location = process.env.GOOGLE_CLOUD_LOCATION || 'global';
+const model = 'gemini-2.5-flash';
+
+describe('tools-func-calling-stream-content', () => {
+  /**
+   * TODO(developer): Uncomment these variables before running the sample.\
+   * (Not necessary if passing values as arguments)
+   */
+  // const projectId = 'YOUR_PROJECT_ID';
+  // const location = 'YOUR_LOCATION';
+  // const model = 'gemini-2.5-flash';
+
+  it('should create stream chat and begin the conversation the same in each instance', async () => {
+    const output = execSync(
+      `node ./tools-func-calling-stream-content.js ${projectId} ${location} ${model}`
+    );
+
+    // Assert that the response is what we expect
+    assert(output.match(/super nice/), output);
+  });
+});

genai/tools/tools-func-calling-stream-content.js

@@ -0,0 +1,96 @@
+// Copyright 2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// [START aiplatform_genai_function_calling_stream_content]
+const {GoogleGenAI} = require('@google/genai');
+
+const tools = [
+  {
+    functionDeclarations: [
+      {
+        name: 'get_current_weather',
+        description: 'get weather in a given location',
+        parameters: {
+          type: 'OBJECT',
+          properties: {
+            location: {type: 'STRING'},
+            unit: {type: 'STRING', enum: ['celsius', 'fahrenheit']},
+          },
+          required: ['location'],
+        },
+      },
+    ],
+  },
+];
+
+const functionResponseParts = [
+  {
+    functionResponse: {
+      name: 'get_current_weather',
+      response: {weather: 'super nice'},
+    },
+  },
+];
+
+/**
+ * TODO(developer): Update these variables before running the sample.
+ */
+async function functionCallingStreamContent(
+  projectId = 'PROJECT_ID',
+  location = 'us-central1',
+  model = 'gemini-2.5-flash'
+) {
+  // Initialize client with your Cloud project and location
+  const client = new GoogleGenAI({
+    vertexai: true,
+    project: projectId,
+    location: location,
+  });
+
+  const request = [
+    {role: 'user', parts: [{text: 'What is the weather in Boston?'}]},
+    {
+      role: 'model',
+      parts: [
+        {
+          functionCall: {
+            name: 'get_current_weather',
+            args: {location: 'Boston'},
+          },
+        },
+      ],
+    },
+    {role: 'user', parts: functionResponseParts},
+  ];
+
+  const streamingResp = await client.models.generateContentStream({
+    model: model,
+    contents: request,
+    config: {tools: tools},
+  });
+
+  let completeResponseText = '';
+  for await (const chunk of streamingResp) {
+    if (chunk.text) {
+      completeResponseText += chunk.text;
+    }
+  }
+  console.log(completeResponseText);
+}
+// [END aiplatform_genai_function_calling_stream_content]
+
+functionCallingStreamContent(...process.argv.slice(2)).catch(err => {
+  console.error(err.message);
+  process.exitCode = 1;
+});