Add reasoningContent support to OpenAiChatModel and related classes (For deepseek-reasoner https://api-docs.deepseek.com/api/create-chat-completion)

- Added reasoningContent field to metadata in OpenAiChatModel
- Updated ChatCompletionMessage to include reasoningContent
- Modified OpenAiStreamFunctionCallingHelper to handle reasoningContent
- Updated tests to verify reasoningContent functionality

Signed-off-by: Alexandros Pappas <[email protected]>

Author: apappascs

models/spring-ai-openai/src/main/java/org/springframework/ai/openai/OpenAiChatModel.java

@@ -258,7 +258,8 @@ public ChatResponse internalCall(Prompt prompt, ChatResponse previousChatRespons
 							"role", choice.message().role() != null ? choice.message().role().name() : "",
 							"index", choice.index(),
 							"finishReason", choice.finishReason() != null ? choice.finishReason().name() : "",
-							"refusal", StringUtils.hasText(choice.message().refusal()) ? choice.message().refusal() : "");
+							"refusal", StringUtils.hasText(choice.message().refusal()) ? choice.message().refusal() : "",
+							"reasoningContent", StringUtils.hasText(choice.message().reasoningContent()) ? choice.message().reasoningContent() : "");
 					// @formatter:on
 					return buildGeneration(choice, metadata, request);
 				}).toList();
@@ -346,7 +347,8 @@ public Flux<ChatResponse> internalStream(Prompt prompt, ChatResponse previousCha
 									"role", roleMap.getOrDefault(id, ""),
 									"index", choice.index(),
 									"finishReason", choice.finishReason() != null ? choice.finishReason().name() : "",
-									"refusal", StringUtils.hasText(choice.message().refusal()) ? choice.message().refusal() : "");
+									"refusal", StringUtils.hasText(choice.message().refusal()) ? choice.message().refusal() : "",
+									"reasoningContent", StringUtils.hasText(choice.message().reasoningContent()) ? choice.message().reasoningContent() : "");
 
 							return buildGeneration(choice, metadata, request);
 						}).toList();
@@ -543,7 +545,7 @@ else if (message.getMessageType() == MessageType.ASSISTANT) {
 
 				}
 				return List.of(new ChatCompletionMessage(assistantMessage.getText(),
-						ChatCompletionMessage.Role.ASSISTANT, null, null, toolCalls, null, audioOutput));
+						ChatCompletionMessage.Role.ASSISTANT, null, null, toolCalls, null, audioOutput, null));
 			}
 			else if (message.getMessageType() == MessageType.TOOL) {
 				ToolResponseMessage toolMessage = (ToolResponseMessage) message;
@@ -553,7 +555,7 @@ else if (message.getMessageType() == MessageType.TOOL) {
 				return toolMessage.getResponses()
 					.stream()
 					.map(tr -> new ChatCompletionMessage(tr.responseData(), ChatCompletionMessage.Role.TOOL, tr.name(),
-							tr.id(), null, null, null))
+							tr.id(), null, null, null, null))
 					.toList();
 			}
 			else {

models/spring-ai-openai/src/main/java/org/springframework/ai/openai/api/OpenAiApi.java

@@ -1138,8 +1138,11 @@ public record StreamOptions(
 	 * {@link Role#ASSISTANT} role and null otherwise.
 	 * @param audioOutput Audio response from the model. >>>>>>> bdb66e577 (OpenAI -
 	 * Support audio input modality)
+	 * @param reasoningContent For deepseek-reasoner model only. The reasoning contents of
+	 * the assistant message, before the final answer.
 	 */
 	@JsonInclude(Include.NON_NULL)
+	@JsonIgnoreProperties(ignoreUnknown = true)
 	public record ChatCompletionMessage(// @formatter:off
 			@JsonProperty("content") Object rawContent,
 			@JsonProperty("role") Role role,
@@ -1148,7 +1151,8 @@ public record ChatCompletionMessage(// @formatter:off
 			@JsonProperty("tool_calls")
 			@JsonFormat(with = JsonFormat.Feature.ACCEPT_SINGLE_VALUE_AS_ARRAY) List<ToolCall> toolCalls,
 			@JsonProperty("refusal") String refusal,
-			@JsonProperty("audio") AudioOutput audioOutput) { // @formatter:on
+			@JsonProperty("audio") AudioOutput audioOutput,
+			@JsonProperty("reasoning_content") String reasoningContent) { // @formatter:on
 
 		/**
 		 * Create a chat completion message with the given content and role. All other
@@ -1157,7 +1161,7 @@ public record ChatCompletionMessage(// @formatter:off
 		 * @param role The role of the author of this message.
 		 */
 		public ChatCompletionMessage(Object content, Role role) {
-			this(content, role, null, null, null, null, null);
+			this(content, role, null, null, null, null, null, null);
 
 		}
 

models/spring-ai-openai/src/main/java/org/springframework/ai/openai/api/OpenAiStreamFunctionCallingHelper.java

@@ -39,6 +39,7 @@
  *
  * @author Christian Tzolov
  * @author Thomas Vitale
+ * @author Alexandros Pappas
  * @since 0.8.1
  */
 public class OpenAiStreamFunctionCallingHelper {
@@ -97,6 +98,8 @@ private ChatCompletionMessage merge(ChatCompletionMessage previous, ChatCompleti
 		String refusal = (current.refusal() != null ? current.refusal() : previous.refusal());
 		ChatCompletionMessage.AudioOutput audioOutput = (current.audioOutput() != null ? current.audioOutput()
 				: previous.audioOutput());
+		String reasoningContent = (current.reasoningContent() != null ? current.reasoningContent()
+				: previous.reasoningContent());
 
 		List<ToolCall> toolCalls = new ArrayList<>();
 		ToolCall lastPreviousTooCall = null;
@@ -126,7 +129,8 @@ private ChatCompletionMessage merge(ChatCompletionMessage previous, ChatCompleti
 				toolCalls.add(lastPreviousTooCall);
 			}
 		}
-		return new ChatCompletionMessage(content, role, name, toolCallId, toolCalls, refusal, audioOutput);
+		return new ChatCompletionMessage(content, role, name, toolCallId, toolCalls, refusal, audioOutput,
+				reasoningContent);
 	}
 
 	private ToolCall merge(ToolCall previous, ToolCall current) {

models/spring-ai-openai/src/test/java/org/springframework/ai/openai/api/tool/OpenAiApiToolFunctionCallIT.java

@@ -44,6 +44,7 @@
  *
  * @author Christian Tzolov
  * @author Thomas Vitale
+ * @author Alexandros Pappas
  */
 @EnabledIfEnvironmentVariable(named = "OPENAI_API_KEY", matches = ".+")
 public class OpenAiApiToolFunctionCallIT {
@@ -129,7 +130,7 @@ public void toolFunctionCall() {
 
 				// extend conversation with function response.
 				messages.add(new ChatCompletionMessage("" + weatherResponse.temp() + weatherRequest.unit(), Role.TOOL,
-						functionName, toolCall.id(), null, null, null));
+						functionName, toolCall.id(), null, null, null, null));
 			}
 		}
 

models/spring-ai-openai/src/test/java/org/springframework/ai/openai/chat/proxy/DeepSeekWithOpenAiChatModelIT.java

@@ -56,6 +56,8 @@
 import org.springframework.context.annotation.Bean;
 import org.springframework.core.convert.support.DefaultConversionService;
 import org.springframework.core.io.Resource;
+import org.springframework.http.ResponseEntity;
+import org.springframework.util.StringUtils;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
@@ -82,6 +84,9 @@ class DeepSeekWithOpenAiChatModelIT {
 	@Value("classpath:/prompts/system-message.st")
 	private Resource systemResource;
 
+	@Autowired
+	private OpenAiApi openAiApi;
+
 	@Autowired
 	private OpenAiChatModel chatModel;
 
@@ -128,9 +133,9 @@ void streamingWithTokenUsage() {
 		var streamingTokenUsage = this.chatModel.stream(prompt).blockLast().getMetadata().getUsage();
 		var referenceTokenUsage = this.chatModel.call(prompt).getMetadata().getUsage();
 
-		assertThat(streamingTokenUsage.getPromptTokens()).isGreaterThan(0);
-		assertThat(streamingTokenUsage.getCompletionTokens()).isGreaterThan(0);
-		assertThat(streamingTokenUsage.getTotalTokens()).isGreaterThan(0);
+		assertThat(streamingTokenUsage.getPromptTokens()).isPositive();
+		assertThat(streamingTokenUsage.getCompletionTokens()).isPositive();
+		assertThat(streamingTokenUsage.getTotalTokens()).isPositive();
 
 		assertThat(streamingTokenUsage.getPromptTokens()).isEqualTo(referenceTokenUsage.getPromptTokens());
 		assertThat(streamingTokenUsage.getCompletionTokens()).isEqualTo(referenceTokenUsage.getCompletionTokens());
@@ -325,6 +330,56 @@ record ActorsFilmsRecord(String actor, List<String> movies) {
 
 	}
 
+	@Test
+	void chatCompletionEntityWithReasoning() {
+		OpenAiApi.ChatCompletionMessage chatCompletionMessage = new OpenAiApi.ChatCompletionMessage(
+				"Explain the theory of relativity", OpenAiApi.ChatCompletionMessage.Role.USER);
+		OpenAiApi.ChatCompletionRequest request = new OpenAiApi.ChatCompletionRequest(List.of(chatCompletionMessage),
+				"deepseek-reasoner", 0.8, false);
+		ResponseEntity<OpenAiApi.ChatCompletion> response = this.openAiApi.chatCompletionEntity(request);
+
+		assertThat(response).isNotNull();
+		assertThat(response.getBody().choices().get(0).message().reasoningContent()).isNotBlank();
+	}
+
+	@Test
+	void chatCompletionStreamWithReasoning() {
+		OpenAiApi.ChatCompletionMessage chatCompletionMessage = new OpenAiApi.ChatCompletionMessage(
+				"Explain the theory of relativity", OpenAiApi.ChatCompletionMessage.Role.USER);
+		OpenAiApi.ChatCompletionRequest request = new OpenAiApi.ChatCompletionRequest(List.of(chatCompletionMessage),
+				"deepseek-reasoner", 0.8, true);
+		Flux<OpenAiApi.ChatCompletionChunk> response = this.openAiApi.chatCompletionStream(request);
+
+		assertThat(response).isNotNull();
+		List<OpenAiApi.ChatCompletionChunk> chunks = response.collectList().block();
+		assertThat(chunks).isNotNull();
+		assertThat(chunks.stream().anyMatch(chunk -> !chunk.choices().get(0).delta().reasoningContent().isBlank()))
+			.isTrue();
+	}
+
+	@Test
+	void chatModelCallWithReasoning() {
+		OpenAiChatModel deepReasoner = new OpenAiChatModel(this.openAiApi,
+				OpenAiChatOptions.builder().model("deepseek-reasoner").build());
+		ChatResponse chatResponse = deepReasoner.call(new Prompt("Explain the theory of relativity"));
+		assertThat(chatResponse.getResults()).isNotEmpty();
+		assertThat(chatResponse.getResults().get(0).getOutput().getMetadata().get("reasoningContent").toString())
+			.isNotBlank();
+	}
+
+	@Test
+	void chatModelStreamWithReasoning() {
+		OpenAiChatModel deepReasoner = new OpenAiChatModel(this.openAiApi,
+				OpenAiChatOptions.builder().model("deepseek-reasoner").build());
+		Flux<ChatResponse> flux = deepReasoner.stream(new Prompt("Explain the theory of relativity"));
+		List<ChatResponse> responses = flux.collectList().block();
+		assertThat(responses).isNotEmpty();
+		assertThat(responses.stream()
+			.flatMap(response -> response.getResults().stream())
+			.map(result -> result.getOutput().getMetadata().get("reasoningContent").toString())
+			.anyMatch(StringUtils::hasText)).isTrue();
+	}
+
 	@SpringBootConfiguration
 	static class Config {