.Net: Fix: include taskType in Google AI embedding request (fixes #13250)

dotnet/src/Connectors/Connectors.Google.UnitTests/Core/GoogleAI/GoogleAIEmbeddingRequestTests.cs

@@ -83,4 +83,25 @@ public void FromDataJsonIncludesDimensionsWhenProvided()
         // Assert
         Assert.Contains($"{DimensionalityJsonPropertyName}:{Dimensions}", json);
     }
+
+    [Fact]
+    public void FromDataShouldIncludeTaskTypeWhenProvided()
+    {
+        // Arrange
+        var input = new[] { "This is a retrieval document." };
+        var modelId = "embedding-001";
+        var dimensions = 1024;
+        var taskType = "RETRIEVAL_DOCUMENT";
+
+        // Act
+        var request = GoogleAIEmbeddingRequest.FromData(input, modelId, dimensions, taskType);
+
+        // Serialize to JSON (this is what would be sent in the HTTP request)
+        var json = System.Text.Json.JsonSerializer.Serialize(request);
+
+        // Assert
+        Assert.Contains("\"taskType\":\"RETRIEVAL_DOCUMENT\"", json);
+        Assert.Contains("\"model\":\"models/embedding-001\"", json);
+    }
+
 }

dotnet/src/Connectors/Connectors.Google/Core/GoogleAI/GoogleAIEmbeddingClient.cs

@@ -6,6 +6,7 @@
 using System.Net.Http;
 using System.Threading;
 using System.Threading.Tasks;
+using Microsoft.Extensions.AI;
 using Microsoft.Extensions.Logging;
 
 namespace Microsoft.SemanticKernel.Connectors.Google.Core;
@@ -54,15 +55,25 @@ public GoogleAIEmbeddingClient(
     /// Generates embeddings for the given data asynchronously.
     /// </summary>
     /// <param name="data">The list of strings to generate embeddings for.</param>
+    /// <param name="options">The embedding generation options.</param>
     /// <param name="cancellationToken">The cancellation token to cancel the operation.</param>
     /// <returns>Result contains a list of read-only memories of floats representing the generated embeddings.</returns>
     public async Task<IList<ReadOnlyMemory<float>>> GenerateEmbeddingsAsync(
         IList<string> data,
+        EmbeddingGenerationOptions? options = null,
         CancellationToken cancellationToken = default)
     {
         Verify.NotNullOrEmpty(data);
 
-        var geminiRequest = this.GetEmbeddingRequest(data);
+        // var geminiRequest = this.GetEmbeddingRequest(data);
+        string? taskType = null;
+        if (options?.AdditionalProperties?.TryGetValue("task_type", out var taskTypeValue) == true)
+        {
+            taskType = taskTypeValue?.ToString();
+        }
+
+        var geminiRequest = this.GetEmbeddingRequest(data, taskType);
+
         using var httpRequestMessage = await this.CreateHttpRequestAsync(geminiRequest, this._embeddingEndpoint).ConfigureAwait(false);
 
         string body = await this.SendRequestAndGetStringBodyAsync(httpRequestMessage, cancellationToken)
@@ -71,8 +82,8 @@ public async Task<IList<ReadOnlyMemory<float>>> GenerateEmbeddingsAsync(
         return DeserializeAndProcessEmbeddingsResponse(body);
     }
 
-    private GoogleAIEmbeddingRequest GetEmbeddingRequest(IEnumerable<string> data)
-        => GoogleAIEmbeddingRequest.FromData(data, this._embeddingModelId, this._dimensions);
+    private GoogleAIEmbeddingRequest GetEmbeddingRequest(IEnumerable<string> data, string? taskType = null)
+    => GoogleAIEmbeddingRequest.FromData(data, this._embeddingModelId, this._dimensions, taskType);
 
     private static List<ReadOnlyMemory<float>> DeserializeAndProcessEmbeddingsResponse(string body)
         => ProcessEmbeddingsResponse(DeserializeResponse<GoogleAIEmbeddingResponse>(body));

dotnet/src/Connectors/Connectors.Google/Core/GoogleAI/GoogleAIEmbeddingRequest.cs

@@ -11,7 +11,7 @@ internal sealed class GoogleAIEmbeddingRequest
     [JsonPropertyName("requests")]
     public IList<RequestEmbeddingContent> Requests { get; set; } = null!;
 
-    public static GoogleAIEmbeddingRequest FromData(IEnumerable<string> data, string modelId, int? dimensions = null) => new()
+    public static GoogleAIEmbeddingRequest FromData(IEnumerable<string> data, string modelId, int? dimensions = null, string? taskType = null) => new()
     {
         Requests = data.Select(text => new RequestEmbeddingContent
         {
@@ -26,7 +26,8 @@ internal sealed class GoogleAIEmbeddingRequest
                     }
                 ]
             },
-            Dimensions = dimensions
+            Dimensions = dimensions,
+            TaskType = taskType
         }).ToList()
     };
 

dotnet/src/Connectors/Connectors.Google/Services/GoogleAITextEmbeddingGenerationService.cs

@@ -5,6 +5,7 @@
 using System.Net.Http;
 using System.Threading;
 using System.Threading.Tasks;
+using Microsoft.Extensions.AI;
 using Microsoft.Extensions.Logging;
 using Microsoft.SemanticKernel.Connectors.Google.Core;
 using Microsoft.SemanticKernel.Embeddings;
@@ -68,6 +69,25 @@ public Task<IList<ReadOnlyMemory<float>>> GenerateEmbeddingsAsync(
         Kernel? kernel = null,
         CancellationToken cancellationToken = default)
     {
-        return this._embeddingClient.GenerateEmbeddingsAsync(data, cancellationToken);
+        return this._embeddingClient.GenerateEmbeddingsAsync(data, null, cancellationToken);
     }
+
+    /// <summary>
+    /// Generates embeddings for the specified input text, allowing additional configuration
+    /// via <see cref="EmbeddingGenerationOptions"/> (e.g., specifying the Google task type).
+    /// </summary>
+    /// <param name="data">The input text collection to generate embeddings for.</param>
+    /// <param name="options">Embedding generation options (e.g., task_type).</param>
+    /// <param name="kernel">Optional Kernel instance.</param>
+    /// <param name="cancellationToken">Token for cancelling the request.</param>
+    /// <returns>A list of generated embeddings.</returns>
+    public Task<IList<ReadOnlyMemory<float>>> GenerateEmbeddingsAsync(
+        IList<string> data,
+        EmbeddingGenerationOptions? options,
+        Kernel? kernel = null,
+        CancellationToken cancellationToken = default)
+    {
+        return this._embeddingClient.GenerateEmbeddingsAsync(data, options, cancellationToken);
+    }
+
 }