feat: support count tokens feature in Models module

Google.GenAI.E2E.Tests/CountTokens/CountTokensTest.cs

@@ -0,0 +1,221 @@
+/*
+ * Copyright 2025 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.
+ */
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+
+using Google.GenAI;
+using Google.GenAI.Types;
+
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+using TestServerSdk;
+
+[TestClass]
+public class CountTokensTest {
+  private static TestServerProcess? _server;
+  private Client vertexClient;
+  private Client geminiClient;
+  private string modelName;
+  public TestContext TestContext { get; set; }
+
+  [ClassInitialize]
+  public static void ClassInit(TestContext _) {
+    _server = TestServer.StartTestServer();
+  }
+
+  [ClassCleanup]
+  public static void ClassCleanup() {
+    TestServer.StopTestServer(_server);
+  }
+
+  [TestInitialize]
+  public void TestInit() {
+    // Test server specific setup.
+    if (_server == null) {
+      throw new InvalidOperationException("Test server is not initialized.");
+    }
+    var geminiClientHttpOptions = new HttpOptions {
+      Headers = new Dictionary<string, string> { { "Test-Name",
+                                                   $"{GetType().Name}.{TestContext.TestName}" } },
+      BaseUrl = "http://localhost:1453"
+    };
+    var vertexClientHttpOptions = new HttpOptions {
+      Headers = new Dictionary<string, string> { { "Test-Name",
+                                                   $"{GetType().Name}.{TestContext.TestName}" } },
+      BaseUrl = "http://localhost:1454"
+    };
+
+    // Common setup for both clients.
+    string project = System.Environment.GetEnvironmentVariable("GOOGLE_CLOUD_PROJECT");
+    string location =
+        System.Environment.GetEnvironmentVariable("GOOGLE_CLOUD_LOCATION") ?? "us-central1";
+    string apiKey = System.Environment.GetEnvironmentVariable("GOOGLE_API_KEY");
+    vertexClient = new Client(project: project, location: location, vertexAI: true,
+                              credential: TestServer.GetCredentialForTestMode(),
+                              httpOptions: vertexClientHttpOptions);
+    geminiClient =
+        new Client(apiKey: apiKey, vertexAI: false, httpOptions: geminiClientHttpOptions);
+
+    // Specific setup for this test class
+    modelName = "gemini-2.5-flash";
+  }
+
+  [TestMethod]
+  public async Task CountTokensVertexTest() {
+    var contents = new List<Content>
+    {
+      new Content
+      {
+        Role = "user",
+        Parts = new List<Part>
+        {
+          new Part
+          {
+              Text = "What is the capital of France?"
+          }
+        }
+      }
+    };
+    var vertexResponse = await vertexClient.Models.CountTokensAsync(
+        model: modelName, contents: contents, config: null);
+
+    Assert.IsNotNull(vertexResponse.TotalTokens);
+  }
+
+  [TestMethod]
+  public async Task CountTokensGeminiTest() {
+    var contents = new List<Content>
+    {
+      new Content
+      {
+        Role = "user",
+        Parts = new List<Part>
+        {
+          new Part
+          {
+              Text = "What is the capital of France?"
+          }
+        }
+      }
+    };
+    var geminiResponse = await geminiClient.Models.CountTokensAsync(
+        model: modelName, contents: contents, config: null);
+
+    Assert.IsNotNull(geminiResponse.TotalTokens);
+  }
+
+  [TestMethod]
+  public async Task CountTokensContentVertexTest() {
+    var contents = new Content
+    {
+      Role = "user",
+      Parts = new List<Part>
+      {
+        new Part
+        {
+            Text = "What is the capital of France?"
+        }
+      }
+    };
+    var vertexResponse = await vertexClient.Models.CountTokensAsync(
+        model: modelName, contents: contents);
+
+    Assert.IsNotNull(vertexResponse.TotalTokens);
+  }
+
+  [TestMethod]
+  public async Task CountTokensContentGeminiTest() {
+    var contents = new Content
+    {
+      Role = "user",
+      Parts = new List<Part>
+      {
+        new Part
+        {
+            Text = "What is the capital of France?"
+        }
+      }
+    };
+    var geminiResponse = await geminiClient.Models.CountTokensAsync(
+        model: modelName, contents: contents);
+
+    Assert.IsNotNull(geminiResponse.TotalTokens);
+  }
+
+  [TestMethod]
+  public async Task CountTokensStringVertexTest() {
+    var vertexResponse = await vertexClient.Models.CountTokensAsync(
+        model: modelName, contents: "What is the capital of France?");
+
+    Assert.IsNotNull(vertexResponse.TotalTokens);
+  }
+
+  [TestMethod]
+  public async Task CountTokensStringGeminiTest() {
+    var geminiResponse = await geminiClient.Models.CountTokensAsync(
+        model: modelName, contents: "What is the capital of France?");
+
+    Assert.IsNotNull(geminiResponse.TotalTokens);
+  }
+
+  [TestMethod]
+  public async Task CountTokensConfigVertexTest() {
+    var config = new CountTokensConfig
+    {
+      SystemInstruction = new Content
+      {
+        Parts = new List<Part>
+        {
+          new Part
+          {
+            Text = "You are a helpful assistant."
+          }
+        }
+      }
+    };
+    var vertexResponse = await vertexClient.Models.CountTokensAsync(
+        model: modelName, contents: "What is the capital of France?", config: config);
+
+    Assert.IsNotNull(vertexResponse.TotalTokens);
+  }
+
+  [TestMethod]
+  public async Task CountTokensConfigGeminiTest() {
+    var config = new CountTokensConfig
+    {
+      SystemInstruction = new Content
+      {
+        Parts = new List<Part>
+        {
+          new Part
+          {
+            Text = "You are a helpful assistant."
+          }
+        }
+      }
+    };
+    var ex = await Assert.ThrowsExceptionAsync<NotSupportedException>(async () => {
+      await geminiClient.Models.CountTokensAsync(
+        model: modelName, contents: "What is the capital of France?", config: config);
+    });
+
+    StringAssert.Contains(ex.Message, "systemInstruction");
+    StringAssert.Contains(ex.Message, "not supported in Gemini API");
+  }
+}

Google.GenAI.E2E.Tests/Recordings/CountTokensTest.CountTokensConfigVertexTest.json

@@ -0,0 +1,67 @@
+{
+  "recordID": "CountTokensTest.CountTokensConfigVertexTest",
+  "interactions": [
+    {
+      "request": {
+        "method": "POST",
+        "url": "/v1beta1/projects/REDACTED/locations/us-central1/publishers/google/models/gemini-2.5-flash:countTokens",
+        "request": "POST /v1beta1/projects/REDACTED/locations/us-central1/publishers/google/models/gemini-2.5-flash:countTokens HTTP/1.1",
+        "headers": {
+          "Content-Length": "154",
+          "Content-Type": "application/json; charset=utf-8",
+          "Test-Name": "CountTokensTest.CountTokensConfigVertexTest"
+        },
+        "bodySegments": [
+          {
+            "contents": [
+              {
+                "parts": [
+                  {
+                    "text": "What is the capital of France?"
+                  }
+                ],
+                "role": "user"
+              }
+            ],
+            "systemInstruction": {
+              "parts": [
+                {
+                  "text": "You are a helpful assistant."
+                }
+              ]
+            }
+          }
+        ],
+        "previousRequest": "b4d6e60a9b97e7b98c63df9308728c5c88c0b40c398046772c63447b94608b4d",
+        "serverAddress": "us-central1-aiplatform.googleapis.com",
+        "port": 443,
+        "protocol": "https"
+      },
+      "shaSum": "fd721119f6ac02e8f92a3bef3156934ed0f425917c6ea5e8af48cd847269c354",
+      "response": {
+        "statusCode": 200,
+        "headers": {
+          "Content-Type": "application/json; charset=UTF-8",
+          "Date": "Tue, 18 Nov 2025 04:52:19 GMT",
+          "Server": "scaffolding on HTTPServer2",
+          "Vary": "Origin, X-Origin, Referer",
+          "X-Content-Type-Options": "nosniff",
+          "X-Frame-Options": "SAMEORIGIN",
+          "X-Xss-Protection": "0"
+        },
+        "bodySegments": [
+          {
+            "promptTokensDetails": [
+              {
+                "modality": "TEXT",
+                "tokenCount": 13
+              }
+            ],
+            "totalBillableCharacters": 49,
+            "totalTokens": 13
+          }
+        ]
+      }
+    }
+  ]
+}

Google.GenAI.E2E.Tests/Recordings/CountTokensTest.CountTokensContentGeminiTest.json

@@ -0,0 +1,60 @@
+{
+  "recordID": "CountTokensTest.CountTokensContentGeminiTest",
+  "interactions": [
+    {
+      "request": {
+        "method": "POST",
+        "url": "/v1beta/models/gemini-2.5-flash:countTokens",
+        "request": "POST /v1beta/models/gemini-2.5-flash:countTokens HTTP/1.1",
+        "headers": {
+          "Content-Length": "82",
+          "Content-Type": "application/json; charset=utf-8",
+          "Test-Name": "CountTokensTest.CountTokensContentGeminiTest"
+        },
+        "bodySegments": [
+          {
+            "contents": [
+              {
+                "parts": [
+                  {
+                    "text": "What is the capital of France?"
+                  }
+                ],
+                "role": "user"
+              }
+            ]
+          }
+        ],
+        "previousRequest": "b4d6e60a9b97e7b98c63df9308728c5c88c0b40c398046772c63447b94608b4d",
+        "serverAddress": "generativelanguage.googleapis.com",
+        "port": 443,
+        "protocol": "https"
+      },
+      "shaSum": "6f82a5a817d114c72184e8c84277173b4ba2ed15d23acfe6f3f2f58278f81f6f",
+      "response": {
+        "statusCode": 200,
+        "headers": {
+          "Content-Type": "application/json; charset=UTF-8",
+          "Date": "Tue, 18 Nov 2025 04:27:12 GMT",
+          "Server": "scaffolding on HTTPServer2",
+          "Server-Timing": "gfet4t7; dur=53",
+          "Vary": "Origin, X-Origin, Referer",
+          "X-Content-Type-Options": "nosniff",
+          "X-Frame-Options": "SAMEORIGIN",
+          "X-Xss-Protection": "0"
+        },
+        "bodySegments": [
+          {
+            "promptTokensDetails": [
+              {
+                "modality": "TEXT",
+                "tokenCount": 8
+              }
+            ],
+            "totalTokens": 8
+          }
+        ]
+      }
+    }
+  ]
+}