feat: [OpenAI] Full Tool call Convenience

foundation-models/openai/src/main/java/com/sap/ai/sdk/foundationmodels/openai/OpenAiChatCompletionResponse.java

@@ -75,21 +75,25 @@ public String getContent() {
    */
   @Nonnull
   public OpenAiAssistantMessage getMessage() {
+    final var toolCalls = getChoice().getMessage().getToolCalls();
+
+    if (toolCalls == null) {
+      return OpenAiMessage.assistant(getContent());
+    }
 
     final List<OpenAiContentItem> contentItems =
         getContent().isEmpty() ? List.of() : List.of(new OpenAiTextItem(getContent()));
 
-    final List toolCalls =
-        getChoice().getMessage().getToolCalls().stream()
-            .map(
+    final var openAiToolCalls =
+        toolCalls.stream()
+            .<OpenAiToolCall>map(
                 toolCall ->
                     new OpenAiFunctionCall(
                         toolCall.getId(),
                         toolCall.getFunction().getName(),
                         toolCall.getFunction().getArguments()))
-            .map(OpenAiToolCall.class::cast)
             .toList();
 
-    return new OpenAiAssistantMessage(new OpenAiMessageContent(contentItems), toolCalls);
+    return new OpenAiAssistantMessage(new OpenAiMessageContent(contentItems), openAiToolCalls);
   }
 }

foundation-models/openai/src/test/java/com/sap/ai/sdk/foundationmodels/openai/OpenAIMessageTest.java

@@ -239,29 +239,6 @@ void throwOnSystemMessageWithImage() {
             "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"))),
-            List.of(
-                new OpenAiFunctionCall("id1", "name1", "arguments1"),
-                new OpenAiFunctionCall("id2", "name2", "arguments2")));
-
-    var toolCalls = message.toolCalls();
-    assertThat(toolCalls).hasSize(2);
-
-    var functionCallItem1 = (OpenAiFunctionCall) toolCalls.get(0);
-    assertThat(functionCallItem1.getId()).isEqualTo("id1");
-    assertThat(functionCallItem1.getName()).isEqualTo("name1");
-    assertThat(functionCallItem1.getArguments()).isEqualTo("arguments1");
-
-    var functionCallItem2 = (OpenAiFunctionCall) toolCalls.get(1);
-    assertThat(functionCallItem2.getId()).isEqualTo("id2");
-    assertThat(functionCallItem2.getName()).isEqualTo("name2");
-    assertThat(functionCallItem2.getArguments()).isEqualTo("arguments2");
-  }
-
   @ParameterizedTest
   @MethodSource("provideValidTextMessageByRole")
   void testCreateChatCompletionRequestMessage(OpenAiMessage message) {

foundation-models/openai/src/test/java/com/sap/ai/sdk/foundationmodels/openai/OpenAiClientGeneratedTest.java

@@ -583,4 +583,45 @@ void chatCompletionTool() {
                   }
                   """)));
   }
+
+  @Test
+  void chatCompletionResponseGetMessage() {
+    stubForChatCompletion();
+
+    final var response = client.chatCompletion(new OpenAiChatCompletionRequest("Some text"));
+    final var simpleMessage = response.getMessage();
+
+    assertThat(simpleMessage).isNotNull();
+    assertThat(simpleMessage.toolCalls()).isEmpty();
+    assertThat(simpleMessage.content().items()).hasSize(1);
+    assertThat(simpleMessage.content().items().get(0)).isInstanceOf(OpenAiTextItem.class);
+    assertThat(((OpenAiTextItem) simpleMessage.content().items().get(0)).text())
+        .isEqualTo(
+            "I'm an AI and cannot answer that question as beauty is subjective and varies from person to person.");
+
+    stubForChatCompletionTool();
+
+    final var responseWithToolCall =
+        client.chatCompletion(new OpenAiChatCompletionRequest("Some tool request"));
+    var messageWithToolCall = responseWithToolCall.getMessage();
+
+    assertThat(messageWithToolCall).isNotNull();
+    assertThat(messageWithToolCall.content().items()).hasSize(0);
+    OpenAiFunctionCall functionCallItem =
+        (OpenAiFunctionCall) messageWithToolCall.toolCalls().get(0);
+    assertThat(functionCallItem.getId()).isEqualTo("call_CUYGJf2j7FRWJMHT3PN3aGxK");
+    assertThat(functionCallItem.getName()).isEqualTo("fibonacci");
+    assertThat(functionCallItem.getArguments()).isEqualTo("{\"N\":12}");
+
+    // case: both content and tool calls are present
+    responseWithToolCall.getChoice().getMessage().content("Some content");
+    var messageWithToolCallsAndContent = responseWithToolCall.getMessage();
+
+    assertThat(messageWithToolCallsAndContent).isNotNull();
+    assertThat(messageWithToolCallsAndContent.content().items()).hasSize(1);
+    assertThat(messageWithToolCallsAndContent.content().items().get(0))
+        .isInstanceOf(OpenAiTextItem.class);
+    assertThat(messageWithToolCallsAndContent.toolCalls().get(0))
+        .isInstanceOf(OpenAiFunctionCall.class);
+  }
 }

foundation-models/openai/src/test/java/com/sap/ai/sdk/foundationmodels/openai/OpenAiClientTest.java

@@ -480,40 +480,4 @@ void chatCompletionTool() {
                       }
                       """)));
   }
-
-  @Test
-  void chatCompletionResponseGetMessage() {
-    stubForChatCompletion();
-
-    final var response = client.chatCompletion(new OpenAiChatCompletionRequest("Some text"));
-    final var simpleMessage = response.getMessage();
-
-    assertThat(simpleMessage).isNotNull();
-    assertThat(simpleMessage.toolCalls()).isEmpty();
-
-    stubForChatCompletionTool();
-
-    final var responseWithToolCall =
-        client.chatCompletion(new OpenAiChatCompletionRequest("Some tool request"));
-    var messageWithToolCall = responseWithToolCall.getMessage();
-
-    assertThat(messageWithToolCall).isNotNull();
-    assertThat(messageWithToolCall.content().items()).hasSize(0);
-    OpenAiFunctionCall functionCallItem =
-        (OpenAiFunctionCall) messageWithToolCall.toolCalls().get(0);
-    assertThat(functionCallItem.getId()).isEqualTo("call_CUYGJf2j7FRWJMHT3PN3aGxK");
-    assertThat(functionCallItem.getName()).isEqualTo("fibonacci");
-    assertThat(functionCallItem.getArguments()).isEqualTo("{\"N\":12}");
-
-    // case: both content and tool calls are present
-    responseWithToolCall.getChoice().getMessage().content("Some content");
-    var messageWithToolCallsAndContent = responseWithToolCall.getMessage();
-
-    assertThat(messageWithToolCallsAndContent).isNotNull();
-    assertThat(messageWithToolCallsAndContent.content().items()).hasSize(1);
-    assertThat(messageWithToolCallsAndContent.content().items().get(0))
-        .isInstanceOf(OpenAiTextItem.class);
-    assertThat(messageWithToolCallsAndContent.toolCalls().get(0))
-        .isInstanceOf(OpenAiFunctionCall.class);
-  }
 }