Simple OpenAI API

README.md

@@ -181,18 +181,29 @@ See [an example pom in our Spring Boot application](e2e-test-app/pom.xml)
 
 ### Simple chat completion
 
+```java
+final OpenAiChatCompletionOutput result =
+    OpenAiClient.forModel(GPT_35_TURBO)
+        .withSystemPrompt("You are a helpful AI")
+        .chatCompletion("Hello World! Why is this phrase so famous?");
+
+final String resultMessage = result.getContent();
+```
+
+### Message history
+
 ```java
 final var systemMessage =
     new OpenAiChatSystemMessage().setContent("You are a helpful assistant");
 final var userMessage =
     new OpenAiChatUserMessage().addText("Hello World! Why is this phrase so famous?");
 final var request =
-    new OpenAiChatCompletionParameters().setMessages(List.of(systemMessage, userMessage));
+    new OpenAiChatCompletionParameters().addMessages(systemMessage, userMessage);
 
 final OpenAiChatCompletionOutput result =
     OpenAiClient.forModel(GPT_35_TURBO).chatCompletion(request);
 
-final String resultMessage = result.getChoices().get(0).getMessage().getContent();
+final String resultMessage = result.getContent();
 ```
 
 See [an example in our Spring Boot application](e2e-test-app/src/main/java/com/sap/ai/sdk/app/controllers/OpenAiController.java)
@@ -213,14 +224,10 @@ This is a blocking example for streaming and printing directly to the console:
 ```java
 String msg = "Can you give me the first 100 numbers of the Fibonacci sequence?";
 
-OpenAiChatCompletionParameters request =
-    new OpenAiChatCompletionParameters()
-        .setMessages(List.of(new OpenAiChatUserMessage().addText(msg)));
-
 OpenAiClient client = OpenAiClient.forModel(GPT_35_TURBO);
 
 // try-with-resources on stream ensures the connection will be closed
-try( Stream<String> stream = client.streamChatCompletion(request)) {
+try( Stream<String> stream = client.streamChatCompletion(msg)) {
     stream.forEach(deltaString -> {
         System.out.print(deltaString);
         System.out.flush();
@@ -239,7 +246,7 @@ String msg = "Can you give me the first 100 numbers of the Fibonacci sequence?";
 
 OpenAiChatCompletionParameters request =
     new OpenAiChatCompletionParameters()
-        .setMessages(List.of(new OpenAiChatUserMessage().addText(msg)));
+        .addMessages(new OpenAiChatUserMessage().addText(msg));
 
 OpenAiChatCompletionOutput totalOutput = new OpenAiChatCompletionOutput();
 OpenAiClient client = OpenAiClient.forModel(GPT_35_TURBO);

e2e-test-app/src/main/java/com/sap/ai/sdk/app/controllers/OpenAiController.java

@@ -41,11 +41,7 @@ class OpenAiController {
   @GetMapping("/chatCompletion")
   @Nonnull
   public static OpenAiChatCompletionOutput chatCompletion() {
-    final var request =
-        new OpenAiChatCompletionParameters()
-            .setMessages(List.of(new OpenAiChatUserMessage().addText("Who is the prettiest")));
-
-    return OpenAiClient.forModel(GPT_35_TURBO).chatCompletion(request);
+    return OpenAiClient.forModel(GPT_35_TURBO).chatCompletion("Who is the prettiest");
   }
 
   /**
@@ -59,8 +55,7 @@ public static OpenAiChatCompletionOutput chatCompletion() {
   public static ResponseEntity<ResponseBodyEmitter> streamChatCompletionDeltas() {
     final var msg = "Can you give me the first 100 numbers of the Fibonacci sequence?";
     final var request =
-        new OpenAiChatCompletionParameters()
-            .setMessages(List.of(new OpenAiChatUserMessage().addText(msg)));
+        new OpenAiChatCompletionParameters().addMessages(new OpenAiChatUserMessage().addText(msg));
 
     final var stream = OpenAiClient.forModel(GPT_35_TURBO).streamChatCompletionDeltas(request);
 
@@ -103,15 +98,11 @@ private static String objectToJson(@Nonnull final Object obj) {
   @GetMapping("/streamChatCompletion")
   @Nonnull
   public static ResponseEntity<ResponseBodyEmitter> streamChatCompletion() {
-    final var request =
-        new OpenAiChatCompletionParameters()
-            .setMessages(
-                List.of(
-                    new OpenAiChatUserMessage()
-                        .addText(
-                            "Can you give me the first 100 numbers of the Fibonacci sequence?")));
-
-    final var stream = OpenAiClient.forModel(GPT_35_TURBO).streamChatCompletion(request);
+    final var stream =
+        OpenAiClient.forModel(GPT_35_TURBO)
+            .withSystemPrompt("Be a good, honest AI and answer the following question:")
+            .streamChatCompletion(
+                "Can you give me the first 100 numbers of the Fibonacci sequence?");
 
     final var emitter = new ResponseBodyEmitter();
 
@@ -150,13 +141,12 @@ private static void send(
   public static OpenAiChatCompletionOutput chatCompletionImage() {
     final var request =
         new OpenAiChatCompletionParameters()
-            .setMessages(
-                List.of(
-                    new OpenAiChatUserMessage()
-                        .addText("Describe the following image.")
-                        .addImage(
-                            "https://upload.wikimedia.org/wikipedia/commons/thumb/5/59/SAP_2011_logo.svg/440px-SAP_2011_logo.svg.png",
-                            ImageDetailLevel.HIGH)));
+            .addMessages(
+                new OpenAiChatUserMessage()
+                    .addText("Describe the following image.")
+                    .addImage(
+                        "https://upload.wikimedia.org/wikipedia/commons/thumb/5/59/SAP_2011_logo.svg/440px-SAP_2011_logo.svg.png",
+                        ImageDetailLevel.HIGH));
 
     return OpenAiClient.forModel(GPT_4O).chatCompletion(request);
   }
@@ -180,7 +170,7 @@ public static OpenAiChatCompletionOutput chatCompletionTools() {
     final var tool = new OpenAiChatCompletionTool().setType(FUNCTION).setFunction(function);
     final var request =
         new OpenAiChatCompletionParameters()
-            .setMessages(List.of(new OpenAiChatUserMessage().addText(question)))
+            .addMessages(new OpenAiChatUserMessage().addText(question))
             .setTools(List.of(tool))
             .setToolChoiceFunction("fibonacci");
 

e2e-test-app/src/test/java/com/sap/ai/sdk/app/controllers/OpenAiTest.java

@@ -7,7 +7,6 @@
 import com.sap.ai.sdk.foundationmodels.openai.model.OpenAiChatCompletionOutput;
 import com.sap.ai.sdk.foundationmodels.openai.model.OpenAiChatCompletionParameters;
 import com.sap.ai.sdk.foundationmodels.openai.model.OpenAiChatMessage.OpenAiChatUserMessage;
-import java.util.List;
 import java.util.concurrent.atomic.AtomicInteger;
 import lombok.extern.slf4j.Slf4j;
 import org.junit.jupiter.api.Test;
@@ -36,7 +35,7 @@ void chatCompletionImage() {
   void streamChatCompletion() {
     final var request =
         new OpenAiChatCompletionParameters()
-            .setMessages(List.of(new OpenAiChatUserMessage().addText("Who is the prettiest?")));
+            .addMessages(new OpenAiChatUserMessage().addText("Who is the prettiest?"));
 
     final var totalOutput = new OpenAiChatCompletionOutput();
     final var filledDeltaCount = new AtomicInteger(0);

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

@@ -10,6 +10,8 @@
 import com.sap.ai.sdk.foundationmodels.openai.model.OpenAiChatCompletionDelta;
 import com.sap.ai.sdk.foundationmodels.openai.model.OpenAiChatCompletionOutput;
 import com.sap.ai.sdk.foundationmodels.openai.model.OpenAiChatCompletionParameters;
+import com.sap.ai.sdk.foundationmodels.openai.model.OpenAiChatMessage.OpenAiChatSystemMessage;
+import com.sap.ai.sdk.foundationmodels.openai.model.OpenAiChatMessage.OpenAiChatUserMessage;
 import com.sap.ai.sdk.foundationmodels.openai.model.OpenAiEmbeddingOutput;
 import com.sap.ai.sdk.foundationmodels.openai.model.OpenAiEmbeddingParameters;
 import com.sap.ai.sdk.foundationmodels.openai.model.StreamedDelta;
@@ -34,6 +36,7 @@
 public final class OpenAiClient {
   private static final String DEFAULT_API_VERSION = "2024-02-01";
   static final ObjectMapper JACKSON;
+  private String systemPrompt = null;
 
   static {
     JACKSON =
@@ -95,6 +98,36 @@ public static OpenAiClient withCustomDestination(@Nonnull final Destination dest
     return new OpenAiClient(destination);
   }
 
+  /**
+   * Add a system prompt before user prompts.
+   *
+   * @param systemPrompt the system prompt
+   * @return the client
+   */
+  @Nonnull
+  public OpenAiClient withSystemPrompt(@Nonnull final String systemPrompt) {
+    this.systemPrompt = systemPrompt;
+    return this;
+  }
+
+  /**
+   * Generate a completion for the given user prompt.
+   *
+   * @param prompt a text message.
+   * @return the completion output
+   * @throws OpenAiClientException if the request fails
+   */
+  @Nonnull
+  public OpenAiChatCompletionOutput chatCompletion(@Nonnull final String prompt)
+      throws OpenAiClientException {
+    final OpenAiChatCompletionParameters parameters = new OpenAiChatCompletionParameters();
+    if (systemPrompt != null) {
+      parameters.addMessages(new OpenAiChatSystemMessage().setContent(systemPrompt));
+    }
+    parameters.addMessages(new OpenAiChatUserMessage().addText(prompt));
+    return chatCompletion(parameters);
+  }
+
   /**
    * Generate a completion for the given prompt.
    *
@@ -105,19 +138,25 @@ public static OpenAiClient withCustomDestination(@Nonnull final Destination dest
   @Nonnull
   public OpenAiChatCompletionOutput chatCompletion(
       @Nonnull final OpenAiChatCompletionParameters parameters) throws OpenAiClientException {
+    warnIfUnsupportedUsage();
     return execute("/chat/completions", parameters, OpenAiChatCompletionOutput.class);
   }
 
   /**
    * Generate a completion for the given prompt.
    *
-   * @param parameters the prompt, including messages and other parameters.
+   * @param prompt a text message.
    * @return A stream of message deltas
    * @throws OpenAiClientException if the request fails or if the finish reason is content_filter
    */
   @Nonnull
-  public Stream<String> streamChatCompletion(
-      @Nonnull final OpenAiChatCompletionParameters parameters) throws OpenAiClientException {
+  public Stream<String> streamChatCompletion(@Nonnull final String prompt)
+      throws OpenAiClientException {
+    final OpenAiChatCompletionParameters parameters = new OpenAiChatCompletionParameters();
+    if (systemPrompt != null) {
+      parameters.addMessages(new OpenAiChatSystemMessage().setContent(systemPrompt));
+    }
+    parameters.addMessages(new OpenAiChatUserMessage().addText(prompt));
     return streamChatCompletionDeltas(parameters)
         .peek(OpenAiClient::throwOnContentFilter)
         .map(OpenAiChatCompletionDelta::getDeltaContent);
@@ -140,10 +179,18 @@ private static void throwOnContentFilter(@Nonnull final OpenAiChatCompletionDelt
   @Nonnull
   public Stream<OpenAiChatCompletionDelta> streamChatCompletionDeltas(
       @Nonnull final OpenAiChatCompletionParameters parameters) throws OpenAiClientException {
+    warnIfUnsupportedUsage();
     parameters.enableStreaming();
     return executeStream("/chat/completions", parameters, OpenAiChatCompletionDelta.class);
   }
 
+  private void warnIfUnsupportedUsage() {
+    if (systemPrompt != null) {
+      log.warn(
+          "Previously set messages will be ignored, set it as an argument of this method instead.");
+    }
+  }
+
   /**
    * Get a vector representation of a given input that can be easily consumed by machine learning
    * models and algorithms.

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

@@ -1,8 +1,10 @@
 package com.sap.ai.sdk.foundationmodels.openai.model;
 
 import com.fasterxml.jackson.annotation.JsonProperty;
+import com.sap.ai.sdk.foundationmodels.openai.OpenAiClientException;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Objects;
 import javax.annotation.Nonnull;
 import lombok.EqualsAndHashCode;
 import lombok.Getter;
@@ -28,6 +30,25 @@ public class OpenAiChatCompletionOutput extends OpenAiCompletionOutput
   @Getter(onMethod_ = @Nonnull)
   private String systemFingerprint;
 
+  /**
+   * Get the message content from the output.
+   *
+   * <p>Note: If there are multiple choices only the first one is returned
+   *
+   * @return the message content or empty string.
+   * @throws OpenAiClientException if the content filter filtered the output.
+   */
+  @Nonnull
+  public String getContent() throws OpenAiClientException {
+    if (getChoices().isEmpty()) {
+      return "";
+    }
+    if ("content_filter".equals(getChoices().get(0).getFinishReason())) {
+      throw new OpenAiClientException("Content filter filtered the output.");
+    }
+    return Objects.requireNonNullElse(getChoices().get(0).getMessage().getContent(), "");
+  }
+
   /**
    * Add a streamed delta to the total output.
    *

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

@@ -6,6 +6,7 @@
 import com.fasterxml.jackson.annotation.JsonSubTypes;
 import com.fasterxml.jackson.annotation.JsonTypeInfo;
 import com.fasterxml.jackson.annotation.JsonValue;
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 import javax.annotation.Nonnull;
@@ -25,7 +26,6 @@
 public class OpenAiChatCompletionParameters extends OpenAiCompletionParameters {
   /** A list of messages comprising the conversation so far. */
   @JsonProperty("messages")
-  @Setter(onParam_ = @Nonnull)
   private List<OpenAiChatMessage> messages;
 
   /**
@@ -197,4 +197,19 @@ private record Function(@JsonProperty("name") @Nonnull String name) {}
   public OpenAiChatCompletionParameters setStop(@Nullable final String... values) {
     return (OpenAiChatCompletionParameters) super.setStop(values);
   }
+
+  /**
+   * Add messages to the conversation.
+   *
+   * @param messages The messages to add.
+   * @return this instance for chaining.
+   */
+  @Nonnull
+  public OpenAiChatCompletionParameters addMessages(@Nonnull final OpenAiChatMessage... messages) {
+    if (this.messages == null) {
+      this.messages = new ArrayList<>();
+    }
+    this.messages.addAll(Arrays.asList(messages));
+    return this;
+  }
 }