Spring AI ChatClient streaming does not work with LM Studio Local LLM API Server

Bug description I ran LM Studio Local LLM API Server (OpenAI compatibility mode). ChatClient.call() API works perfectly, but the ChatClient.stream() does not work!

I enabled debug logs and also used the SimpleLoggerAdvisor and saw this log for streaming:

DEBUG 54629 --- [streaming] [nio-8080-exec-6] o.s.web.servlet.DispatcherServlet        : POST "/stream", parameters={}
DEBUG 54629 --- [streaming] [nio-8080-exec-6] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped to dev.danvega.streaming.ChatController#chatWithStream(String)
DEBUG 54629 --- [streaming] [nio-8080-exec-6] m.m.a.RequestResponseBodyMethodProcessor : Read "application/json;charset=UTF-8" to ["{"message": "What is the largest country on Earth?"}"]
DEBUG 54629 --- [streaming] [nio-8080-exec-6] o.s.a.c.c.advisor.SimpleLoggerAdvisor    : request: AdvisedRequest[chatModel=OpenAiChatModel [defaultOptions=OpenAiChatOptions: {"streamUsage":false,"model":"meta-llama-3.1-8b-instruct","temperature":0.7}], userText={"message": "What is the largest country on Earth?"}, systemText=, chatOptions=OpenAiChatOptions: {"streamUsage":false,"model":"meta-llama-3.1-8b-instruct","temperature":0.7}, media=[], functionNames=[], functionCallbacks=[], messages=[], userParams={}, systemParams={}, advisors=[org.springframework.ai.chat.client.advisor.observation.ObservableRequestResponseAdvisor@6e5f4d0], advisorParams={}]
DEBUG 54629 --- [streaming] [nio-8080-exec-6] o.s.w.r.f.client.ExchangeFunctions       : [8220a7c] HTTP POST http://localhost:1234/v1/chat/completions
DEBUG 54629 --- [streaming] [nio-8080-exec-6] o.s.http.codec.json.Jackson2JsonEncoder  : [8220a7c] Encoding [ChatCompletionRequest[messages=[ChatCompletionMessage[rawContent={"message": "What is the largest co (truncated)...]
DEBUG 54629 --- [streaming] [nio-8080-exec-6] o.s.w.c.request.async.WebAsyncManager    : Started async request for "/stream"
DEBUG 54629 --- [streaming] [nio-8080-exec-6] o.s.web.servlet.DispatcherServlet        : Exiting but response remains open for further handling

But I could not see anything in the LM Studio server log!

Environment Spring AI version: 1.0.0-M6 Java version: 21 OS: macOS and Windows 11

Steps to reproduce I used the spring-ai-openai-spring-boot-starter lib with this configuration:

  ai:
    openai:
      api-key: lm-studio
      base-url: http://localhost:1234
      chat:
        options:
          model: meta-llama-3.1-8b-instruct
      embedding:
        options:
          model: text-embedding-nomic-embed-text-v1.5-embedding

Expected behavior When I call LM Studio Local LLM API Server (OpenAI compatibility mode) using the curl command (with stream enabled), the ChatClient.call() API also works with the above configuration.

Minimal Complete Reproducible example You can run an LM Studio Local LLM API Server (OpenAI compatibility mode) and clone this example from @danvega and apply my my configs. You will see that the ChatClient.call() works, but the stream() does not!

Comment From: dev-jonghoonpark

LM Studio Local LLM API Server (OpenAI compatibility mode)

The link seems to be invalid, returning a 404 error.