Implement IEmbeddingGenerator interface on top of Embedder.EmbedderClient

[Copilot]

• Create GrokEmbeddingGenerator class implementing IEmbeddingGenerator<string, Embedding<float>>
• Add extension methods to GrokClientExtensions for creating embedding generators
• Add null validation to extension methods
• Create tests for the new embedding generator implementation
• Ensure build and tests pass
• Address code review feedback: use pattern matching for null check

Summary

This PR implements the IEmbeddingGenerator<string, Embedding<float>> interface on top of the Embedder.EmbedderClient from the xAI Protocol. The implementation follows the same patterns as the existing GrokChatClient implementation and the reference OpenAI implementation from the dotnet/extensions repository.

Changes

1. New GrokEmbeddingGenerator class (src/xAI/GrokEmbeddingGenerator.cs)

   • Implements IEmbeddingGenerator<string, Embedding<float>>
   • GenerateAsync method converts input strings to EmbedInput protocol messages and calls the gRPC Embed service
   • Supports model ID from options or default
   • Supports EndUserId from client options
   • GetService implementation returns metadata and underlying client
   • Maps EmbeddingUsage response to UsageDetails

2. Extension methods in GrokClientExtensions (src/xAI/GrokClientExtensions.cs)

   • AsIEmbeddingGenerator(this GrokClient client, string defaultModelId)
   • AsIEmbeddingGenerator(this Embedder.EmbedderClient client, string defaultModelId)
   • Added null validation using Throw.IfNull for all extension methods

3. Comprehensive tests (src/xAI.Tests/EmbeddingGeneratorTests.cs)

   • Integration test with actual API (requires XAI_API_KEY)
   • Null argument validation
   • Metadata retrieval
   • GetService returning proper types
   • Full request/response flow with usage details
   • Missing usage handling
   • Custom model ID support

Original prompt

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This section details on the original issue you should resolve

<issue_title>Implement IEmbeddingGenerator interface on top of Embedder.EmbedderClient</issue_title>
<issue_description>Inspect how OpenAI is implemented:

• https://github.com/dotnet/extensions/blob/main/src/Libraries/Microsoft.Extensions.AI.OpenAI/OpenAIEmbeddingGenerator.cs
• https://github.com/dotnet/extensions/blob/main/test/Libraries/Microsoft.Extensions.AI.OpenAI.Tests/OpenAIEmbeddingGeneratorTests.cs

<agent_instructions>Create implementation and tests</agent_instructions>

Comments on the Issue (you are @copilot in this section)

• Fixes Implement IEmbeddingGenerator interface on top of Embedder.EmbedderClient #40

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[kzu]

🧪 Details on Ubuntu 24.04.3 LTS

from retest v1.1.0 on .NET 10.0.1 with 💜 by @devlooped

[Copilot]

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