First version

rpanackal · rpanackal · commit 9a5aec3c5de2 · 2025-03-26T16:24:02.000+01:00
- Mostly tested
- API design complete
- Function Call as message content item
- Non nullability of `Message.content()`
diff --git a/foundation-models/openai/src/main/java/com/sap/ai/sdk/foundationmodels/openai/OpenAiAssistantMessage.java b/foundation-models/openai/src/main/java/com/sap/ai/sdk/foundationmodels/openai/OpenAiAssistantMessage.java
@@ -3,8 +3,11 @@
 import static lombok.AccessLevel.PACKAGE;
 
 import com.google.common.annotations.Beta;
+import com.sap.ai.sdk.foundationmodels.openai.generated.model.ChatCompletionMessageToolCall;
+import com.sap.ai.sdk.foundationmodels.openai.generated.model.ChatCompletionMessageToolCallFunction;
 import com.sap.ai.sdk.foundationmodels.openai.generated.model.ChatCompletionRequestAssistantMessage;
 import com.sap.ai.sdk.foundationmodels.openai.generated.model.ChatCompletionRequestAssistantMessageContent;
+import com.sap.ai.sdk.foundationmodels.openai.generated.model.ToolCallType;
 import java.util.List;
 import javax.annotation.Nonnull;
 import lombok.AllArgsConstructor;
@@ -21,7 +24,7 @@
 @Value
 @Accessors(fluent = true)
 @AllArgsConstructor(access = PACKAGE)
-class OpenAiAssistantMessage implements OpenAiMessage {
+public class OpenAiAssistantMessage implements OpenAiMessage {
 
   /** The role associated with this message. */
   @Nonnull String role = "assistant";
@@ -32,24 +35,52 @@ class OpenAiAssistantMessage implements OpenAiMessage {
   OpenAiMessageContent content;
 
   /**
-   * Creates a new assistant message with the given single message.
+   * Creates a new assistant message with the given single message as text content.
    *
    * @param singleMessage the message.
    */
   OpenAiAssistantMessage(@Nonnull final String singleMessage) {
     this(new OpenAiMessageContent(List.of(new OpenAiTextItem(singleMessage))));
   }
 
+  @Nonnull
+  public List<OpenAiToolCallItem> getToolCalls() {
+    return this.content().items().stream()
+        .filter(item -> item instanceof OpenAiToolCallItem)
+        .map(item -> (OpenAiToolCallItem) item)
+        .toList();
+  }
+
   /**
    * Converts the message to a serializable object.
    *
    * @return the corresponding {@code ChatCompletionRequestAssistantMessage} object.
    */
   @Nonnull
   ChatCompletionRequestAssistantMessage createChatCompletionRequestMessage() {
-    final var textItem = (OpenAiTextItem) this.content().items().get(0);
-    return new ChatCompletionRequestAssistantMessage()
-        .role(ChatCompletionRequestAssistantMessage.RoleEnum.fromValue(role()))
-        .content(ChatCompletionRequestAssistantMessageContent.create(textItem.text()));
+    var message =
+        new ChatCompletionRequestAssistantMessage()
+            .role(ChatCompletionRequestAssistantMessage.RoleEnum.fromValue(role()));
+
+    for (var item : content().items()) {
+      if (item instanceof OpenAiTextItem textItem) {
+        message.content(ChatCompletionRequestAssistantMessageContent.create(textItem.text()));
+      } else if (item instanceof OpenAiFunctionCallItem functionItem) {
+
+        var functionCall =
+            new ChatCompletionMessageToolCallFunction()
+                .name(functionItem.getName())
+                .arguments(functionItem.getArguments());
+
+        var toolCall =
+            new ChatCompletionMessageToolCall()
+                .type(ToolCallType.FUNCTION)
+                .id(functionItem.getId())
+                .function(functionCall);
+
+        message.addToolCallsItem(toolCall);
+      }
+    }
+    return message;
   }
 }
diff --git a/foundation-models/openai/src/main/java/com/sap/ai/sdk/foundationmodels/openai/OpenAiChatCompletionRequest.java b/foundation-models/openai/src/main/java/com/sap/ai/sdk/foundationmodels/openai/OpenAiChatCompletionRequest.java
@@ -9,6 +9,7 @@
 import com.sap.ai.sdk.foundationmodels.openai.generated.model.CreateChatCompletionRequestAllOfResponseFormat;
 import com.sap.ai.sdk.foundationmodels.openai.generated.model.CreateChatCompletionRequestAllOfStop;
 import java.math.BigDecimal;
+import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
@@ -149,8 +150,18 @@ public OpenAiChatCompletionRequest(@Nonnull final String message) {
   @Tolerate
   public OpenAiChatCompletionRequest(
       @Nonnull final OpenAiMessage message, @Nonnull final OpenAiMessage... messages) {
+    this(Lists.asList(message, messages));
+  }
+
+  /**
+   * Creates an OpenAiChatCompletionPrompt with a list of messages.
+   *
+   * @param messages the list of messages to be added to the prompt
+   */
+  @Tolerate
+  public OpenAiChatCompletionRequest(@Nonnull final List<OpenAiMessage> messages) {
     this(
-        Lists.asList(message, messages),
+        Collections.unmodifiableList(messages),
         null,
         null,
         null,
diff --git a/foundation-models/openai/src/main/java/com/sap/ai/sdk/foundationmodels/openai/OpenAiChatCompletionResponse.java b/foundation-models/openai/src/main/java/com/sap/ai/sdk/foundationmodels/openai/OpenAiChatCompletionResponse.java
@@ -8,6 +8,7 @@
 import com.sap.ai.sdk.foundationmodels.openai.generated.model.CompletionUsage;
 import com.sap.ai.sdk.foundationmodels.openai.generated.model.CreateChatCompletionResponse;
 import com.sap.ai.sdk.foundationmodels.openai.generated.model.CreateChatCompletionResponseChoicesInner;
+import java.util.ArrayList;
 import java.util.Objects;
 import javax.annotation.Nonnull;
 import lombok.RequiredArgsConstructor;
@@ -61,4 +62,27 @@ public String getContent() {
 
     return Objects.requireNonNullElse(getChoice().getMessage().getContent(), "");
   }
+
+  @Nonnull
+  public OpenAiAssistantMessage getMessage() {
+
+    if (getChoice().getMessage().getToolCalls() == null) {
+      return OpenAiMessage.assistant(getContent());
+    }
+
+    var contentItems = new ArrayList<OpenAiContentItem>();
+    if (getContent().isEmpty()) {
+      contentItems.add(new OpenAiTextItem(getContent()));
+    }
+
+    for (var toolCall : getChoice().getMessage().getToolCalls()) {
+      contentItems.add(
+          new OpenAiFunctionCallItem(
+              toolCall.getId(),
+              toolCall.getFunction().getName(),
+              toolCall.getFunction().getArguments()));
+    }
+
+    return new OpenAiAssistantMessage(new OpenAiMessageContent(contentItems));
+  }
 }
diff --git a/foundation-models/openai/src/main/java/com/sap/ai/sdk/foundationmodels/openai/OpenAiContentItem.java b/foundation-models/openai/src/main/java/com/sap/ai/sdk/foundationmodels/openai/OpenAiContentItem.java
@@ -8,4 +8,5 @@
  * @since 1.4.0
  */
 @Beta
-public sealed interface OpenAiContentItem permits OpenAiTextItem, OpenAiImageItem {}
+public sealed interface OpenAiContentItem
+    permits OpenAiTextItem, OpenAiImageItem, OpenAiToolCallItem {}
diff --git a/foundation-models/openai/src/main/java/com/sap/ai/sdk/foundationmodels/openai/OpenAiFunctionCallItem.java b/foundation-models/openai/src/main/java/com/sap/ai/sdk/foundationmodels/openai/OpenAiFunctionCallItem.java
@@ -0,0 +1,18 @@
+package com.sap.ai.sdk.foundationmodels.openai;
+
+import javax.annotation.Nonnull;
+
+import com.google.common.annotations.Beta;
+import lombok.AllArgsConstructor;
+import lombok.Value;
+
+@Beta
+@Value
+@AllArgsConstructor(access = lombok.AccessLevel.PACKAGE)
+public class OpenAiFunctionCallItem implements OpenAiToolCallItem {
+  @Nonnull String type = "function";
+
+  @Nonnull String id;
+  @Nonnull String name;
+  @Nonnull String arguments;
+}
diff --git a/foundation-models/openai/src/main/java/com/sap/ai/sdk/foundationmodels/openai/OpenAiToolCallItem.java b/foundation-models/openai/src/main/java/com/sap/ai/sdk/foundationmodels/openai/OpenAiToolCallItem.java
@@ -0,0 +1,4 @@
+package com.sap.ai.sdk.foundationmodels.openai;
+
+public sealed interface OpenAiToolCallItem extends OpenAiContentItem
+    permits OpenAiFunctionCallItem {}
diff --git a/foundation-models/openai/src/main/java/com/sap/ai/sdk/foundationmodels/openai/OpenAiUtils.java b/foundation-models/openai/src/main/java/com/sap/ai/sdk/foundationmodels/openai/OpenAiUtils.java
@@ -34,7 +34,10 @@ static ChatCompletionRequestMessage createChatCompletionRequestMessage(
       return assistantMessage.createChatCompletionRequestMessage();
     } else if (message instanceof OpenAiSystemMessage systemMessage) {
       return systemMessage.createChatCompletionRequestMessage();
-    } else {
+    } else if(message instanceof OpenAiToolMessage toolMessage) {
+      return toolMessage.createChatCompletionRequestMessage();
+    }
+    else {
       throw new IllegalArgumentException("Unknown message type: " + message.getClass());
     }
   }
diff --git a/foundation-models/openai/src/test/java/com/sap/ai/sdk/foundationmodels/openai/OpenAIMessageTest.java b/foundation-models/openai/src/test/java/com/sap/ai/sdk/foundationmodels/openai/OpenAIMessageTest.java
@@ -1,6 +1,7 @@
 package com.sap.ai.sdk.foundationmodels.openai;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatNoException;
 
 import com.sap.ai.sdk.foundationmodels.openai.generated.model.ChatCompletionRequestAssistantMessage;
 import com.sap.ai.sdk.foundationmodels.openai.generated.model.ChatCompletionRequestAssistantMessageContent;
@@ -13,6 +14,7 @@
 import com.sap.ai.sdk.foundationmodels.openai.generated.model.ChatCompletionRequestToolMessageContent;
 import com.sap.ai.sdk.foundationmodels.openai.generated.model.ChatCompletionRequestUserMessage;
 import com.sap.ai.sdk.foundationmodels.openai.generated.model.ChatCompletionRequestUserMessageContent;
+import com.sap.ai.sdk.foundationmodels.openai.generated.model.ToolCallType;
 import java.net.URI;
 import java.util.List;
 import java.util.stream.Stream;
@@ -194,6 +196,22 @@ void assistantMessageToDto() {
             ((ChatCompletionRequestAssistantMessageContent.InnerString) requestMessage.getContent())
                 .value())
         .isEqualTo(validText);
+
+    var messageWithFunctionCall =
+        new OpenAiAssistantMessage(
+            new OpenAiMessageContent(
+                List.of(new OpenAiFunctionCallItem("id", "name", "arguments"))));
+    var requestMessageWithFunctionCall =
+        messageWithFunctionCall.createChatCompletionRequestMessage();
+
+    assertThat(requestMessageWithFunctionCall.getToolCalls()).hasSize(1);
+    assertThat(requestMessageWithFunctionCall.getToolCalls().get(0).getType())
+        .isEqualTo(ToolCallType.FUNCTION);
+    assertThat(requestMessageWithFunctionCall.getToolCalls().get(0).getId()).isEqualTo("id");
+    assertThat(requestMessageWithFunctionCall.getToolCalls().get(0).getFunction().getName())
+        .isEqualTo("name");
+    assertThat(requestMessageWithFunctionCall.getToolCalls().get(0).getFunction().getArguments())
+        .isEqualTo("arguments");
   }
 
   @Test
@@ -220,4 +238,35 @@ void throwOnSystemMessageWithImage() {
         .hasMessageContaining(
             "Unknown content type for class com.sap.ai.sdk.foundationmodels.openai.OpenAiImageItem messages.");
   }
+
+  @Test
+  void assistantMessageGetToolCalls() {
+    var message =
+        new OpenAiAssistantMessage(
+            new OpenAiMessageContent(
+                List.of(
+                    new OpenAiTextItem("text"),
+                    new OpenAiFunctionCallItem("id1", "name1", "arguments1"),
+                    new OpenAiFunctionCallItem("id2", "name2", "arguments2"))));
+
+    var toolCalls = message.getToolCalls();
+    assertThat(toolCalls).hasSize(2);
+
+    var functionCallItem1 = (OpenAiFunctionCallItem) toolCalls.get(0);
+    assertThat(functionCallItem1.getId()).isEqualTo("id1");
+    assertThat(functionCallItem1.getName()).isEqualTo("name1");
+    assertThat(functionCallItem1.getArguments()).isEqualTo("arguments1");
+
+    var functionCallItem2 = (OpenAiFunctionCallItem) toolCalls.get(1);
+    assertThat(functionCallItem2.getId()).isEqualTo("id2");
+    assertThat(functionCallItem2.getName()).isEqualTo("name2");
+    assertThat(functionCallItem2.getArguments()).isEqualTo("arguments2");
+  }
+
+  @ParameterizedTest
+  @MethodSource("provideValidTextMessageByRole")
+  void verifyAllMessageTypesMappedToDto(OpenAiMessage message) {
+    assertThatNoException()
+        .isThrownBy(() -> OpenAiUtils.createChatCompletionRequestMessage(message));
+  }
 }
diff --git a/foundation-models/openai/src/test/java/com/sap/ai/sdk/foundationmodels/openai/OpenAiChatCompletionRequestTest.java b/foundation-models/openai/src/test/java/com/sap/ai/sdk/foundationmodels/openai/OpenAiChatCompletionRequestTest.java
@@ -8,6 +8,8 @@
 import com.sap.ai.sdk.foundationmodels.openai.generated.model.CreateChatCompletionRequestAllOfStop;
 import java.math.BigDecimal;
 import java.util.List;
+
+import lombok.ToString;
 import org.junit.jupiter.api.Test;
 
 class OpenAiChatCompletionRequestTest {
diff --git a/sample-code/spring-app/src/test/java/com/sap/ai/sdk/app/controllers/OpenAiV2Test.java b/sample-code/spring-app/src/test/java/com/sap/ai/sdk/app/controllers/OpenAiV2Test.java
@@ -112,4 +112,14 @@ void chatCompletionToolExecution() {
     assertThat(content).isNotEmpty();
     assertThat(content).contains("°C");
   }
+
+  @Test
+  void chatCompletionToolExecutionConvenience() {
+    final var completion = service.chatCompletionToolExecutionConvenience("Dubai", "°C");
+
+    String content = completion.getContent();
+
+    assertThat(content).isNotEmpty();
+    assertThat(content).contains("°C");
+  }
 }
diff --git a/sample-code/spring-app/src/test/java/com/sap/ai/sdk/app/services/OpenAiServiceV2.java b/sample-code/spring-app/src/test/java/com/sap/ai/sdk/app/services/OpenAiServiceV2.java
@@ -15,6 +15,7 @@
 import com.sap.ai.sdk.foundationmodels.openai.OpenAiClient;
 import com.sap.ai.sdk.foundationmodels.openai.OpenAiEmbeddingRequest;
 import com.sap.ai.sdk.foundationmodels.openai.OpenAiEmbeddingResponse;
+import com.sap.ai.sdk.foundationmodels.openai.OpenAiFunctionCallItem;
 import com.sap.ai.sdk.foundationmodels.openai.OpenAiImageItem;
 import com.sap.ai.sdk.foundationmodels.openai.OpenAiMessage;
 import com.sap.ai.sdk.foundationmodels.openai.OpenAiToolChoice;
@@ -29,6 +30,7 @@
 import com.sap.ai.sdk.foundationmodels.openai.generated.model.CreateChatCompletionResponse;
 import com.sap.ai.sdk.foundationmodels.openai.generated.model.FunctionObject;
 import io.vavr.control.Try;
+import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
 import java.util.stream.Stream;
@@ -197,6 +199,61 @@ public CreateChatCompletionResponse chatCompletionToolExecution(
     return client.chatCompletion(request);
   }
 
+  public OpenAiChatCompletionResponse chatCompletionToolExecutionConvenience(
+      @Nonnull final String location, @Nonnull final String unit) {
+    // 1. Create tool
+    // 1.1 Create schema for tool: Convenience?
+    final var schemaMap =
+        Try.of(() -> new JsonSchemaGenerator(JACKSON).generateSchema(WeatherMethod.Request.class))
+            .map(schema -> JACKSON.convertValue(schema, Map.class))
+            .getOrElseThrow(
+                e ->
+                    new IllegalArgumentException(
+                        "Could not generate schema for WeatherMethod.Request", e));
+
+    // 1.2 Create function object
+    final var function =
+        new FunctionObject()
+            .name("weather")
+            .description("Get the weather for the given location")
+            .parameters(schemaMap);
+    final var tool = new ChatCompletionTool().type(FUNCTION).function(function);
+
+    // 2. Manage messages externally
+    var messages = new ArrayList<OpenAiMessage>();
+    messages.add(OpenAiMessage.user("What's the weather in %s in %s?".formatted(location, unit)));
+
+    // 3. Create chat completion request
+    var request = new OpenAiChatCompletionRequest(messages).withTools(List.of(tool));
+
+    // 4. Execute chat completion request
+    var initialResponse = OpenAiClient.forModel(GPT_4O_MINI).chatCompletion(request);
+
+    // 5. Extract tool call
+    var assistantMessage = initialResponse.getMessage();
+    messages.add(assistantMessage);
+
+    var functionCall = (OpenAiFunctionCallItem) assistantMessage.getToolCalls().get(0);
+
+    // 6. Execute tool
+    String toolResponseJson;
+    try {
+      var weatherRequest =
+          JACKSON.readValue(functionCall.getArguments(), WeatherMethod.Request.class);
+      final var toolResponse = new WeatherMethod().getCurrentWeather(weatherRequest);
+      toolResponseJson = JACKSON.writeValueAsString(toolResponse);
+    } catch (JsonProcessingException e) {
+      throw new IllegalArgumentException("Error parsing tool call arguments", e);
+    }
+
+    // 7. Create tool message
+    var toolMessage = OpenAiMessage.tool(toolResponseJson, functionCall.getId());
+    messages.add(toolMessage);
+
+    // 9. Execute chat completion request with tool rsponse
+    return OpenAiClient.forModel(GPT_4O_MINI).chatCompletion(request.withMessages(messages));
+  }
+
   /**
    * Get the embedding of a text
    *

Original file line number	Diff line number	Diff line change
`@@ -34,7 +34,10 @@ static ChatCompletionRequestMessage createChatCompletionRequestMessage(`
`34`	`34`	`return assistantMessage.createChatCompletionRequestMessage();`
`35`	`35`	`} else if (message instanceof OpenAiSystemMessage systemMessage) {`
`36`	`36`	`return systemMessage.createChatCompletionRequestMessage();`
`37`		`- } else {`
	`37`	`+ } else if(message instanceof OpenAiToolMessage toolMessage) {`
	`38`	`+ return toolMessage.createChatCompletionRequestMessage();`
	`39`	`+ }`
	`40`	`+ else {`
`38`	`41`	`throw new IllegalArgumentException("Unknown message type: " + message.getClass());`
`39`	`42`	`}`
`40`	`43`	`}`