Spring AI Getting "unable to find valid certification path to requested target" while using custom LLM model endpoint hosted by our company

[saikatHi6]

I am using Spring Boot AI for LLM base application. My company hosted its LLM models at https://dummy-server.xyz.com/. To test how it works, I have taken an example from Spring AI official site and tried from locally. But getting the below error. I have tried to bypass the SSL certificate validation, but that is also not working. Any idea how to resolve it? Please find the error message and my code.

@RestController
  public class ChatController {
  
      private final OpenAiChatModel chatModel;
  
      @Autowired
      public ChatController(@Qualifier("openAiChatModel") OpenAiChatModel chatModel) {
          this.chatModel = chatModel;
      }
  
      @GetMapping("/ai/generate")
      public Map<String,String> generate(@RequestParam(value = "message", defaultValue = "Tell me a joke") String message) {
          return Map.of("generation", this.chatModel.call(message));
      }
  
      @GetMapping("/ai/generateStream")
      public Flux<ChatResponse> generateStream(@RequestParam(value = "message", defaultValue = "Tell me a joke") String message) {
          Prompt prompt = new Prompt(new UserMessage(message));
          return this.chatModel.stream(prompt);
      }
  }

  @Configuration
  public class ChatClientConfig {
  
      @Bean
      public OpenAiChatModel openAiChatModel(@Qualifier("unsafeWebClientBuilder") WebClient unsafeWebClientBuilder) {
          OpenAiApi openAiApi = new OpenAiApi("https://dummy-server.xyz.com/","OTBjZWUxMjAtYWZkNi00Mm5sdsGH", RestClient.builder(),unsafeWebClientBuilder.mutate());
          return new OpenAiChatModel(openAiApi);
      }
  }

  @Configuration
  public class UnsafeWebClientConfig {
      @Bean
      public WebClient unsafeWebClientBuilder() throws NoSuchAlgorithmException, KeyManagementException {
          HttpClient httpClient = HttpClient.create()
                  .secure(sslContextSpec -> {
                      try {
                          sslContextSpec.sslContext(SslContextBuilder.forClient()
                                  .trustManager(InsecureTrustManagerFactory.INSTANCE)
                                  .build());
                      } catch (SSLException e) {
                          throw new RuntimeException("Failed to create SSL context", e);
                      }
                  });
  
          return WebClient.builder()
                  .clientConnector(new ReactorClientHttpConnector(httpClient))
                  .build();
  
      }
  }

To bypass certificate I tried other methods also available on the web, like "X509Certificate"

Error:

    org.springframework.web.client.ResourceAccessException: I/O error on POST request for "https://dummy-server.xyz.com/v1/v1/chat/completions": PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
    	
    org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'chatController' defined in file [C:\Users\Administrator\Documents\spring-ai-multi-llm-chat-svc-main\spring-ai-multi-llm-chat-svc-main\target\classes\com\raj\nola\llm\chat\controller\ChatController.class]: Unsatisfied dependency expressed through constructor parameter 0: Error creating bean with name 'openAiChatModel' defined in class path resource [com/raj/nola/llm/chat/controller/OpenAiClientConfig.class]: Unsatisfied dependency expressed through method 'openAiChatModel' parameter 0: Error creating bean with name 'openAiApi' defined in class path resource [com/raj/nola/llm/chat/controller/OpenAiClientConfig.class]: Failed to instantiate [org.springframework.ai.openai.api.OpenAiApi]: Factory method 'openAiApi' threw exception with message: class org.springframework.web.reactive.function.client.DefaultWebClient cannot be cast to class org.springframework.web.reactive.function.client.WebClient$Builder (org.springframework.web.reactive.function.client.DefaultWebClient and org.springframework.web.reactive.function.client.WebClient$Builder are in unnamed module of loader 'app')

The interesting thing is same endpoint I can use from Python. I tried this simple code and it works like a charm.

httpx_client = httpx.Client(verify=False) 
  llm = OpenAI(
               base_url="https://dummy-server.xyz.com/v1",
               model_name=model_name,
               temperature=0.9, 
               api_key='OTBjZWUxMjAtYWZkNi00MmM5LWE1YWMtMzRmZjVkYzg0NTk0',
               http_client=httpx_client
      )

I am not sure how to resolve this issue. So if anyone can help.