Add unit tests for LlamaChatCompletionRequestEntity to validate message serialization

Author: Jan-Kazlouski-elastic

x-pack/plugin/inference/src/test/java/org/elasticsearch/xpack/inference/services/llama/request/completion/LlamaChatCompletionRequestEntityTests.java

@@ -0,0 +1,64 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+package org.elasticsearch.xpack.inference.services.llama.request.completion;
+
+import org.elasticsearch.common.Strings;
+import org.elasticsearch.common.xcontent.XContentHelper;
+import org.elasticsearch.inference.UnifiedCompletionRequest;
+import org.elasticsearch.test.ESTestCase;
+import org.elasticsearch.xcontent.ToXContent;
+import org.elasticsearch.xcontent.XContentBuilder;
+import org.elasticsearch.xcontent.json.JsonXContent;
+import org.elasticsearch.xpack.inference.external.http.sender.UnifiedChatInput;
+import org.elasticsearch.xpack.inference.services.llama.completion.LlamaChatCompletionModel;
+import org.elasticsearch.xpack.inference.services.llama.completion.LlamaChatCompletionModelTests;
+
+import java.io.IOException;
+import java.util.ArrayList;
+
+public class LlamaChatCompletionRequestEntityTests extends ESTestCase {
+    private static final String ROLE = "user";
+
+    public void testModelUserFieldsSerialization() throws IOException {
+        UnifiedCompletionRequest.Message message = new UnifiedCompletionRequest.Message(
+            new UnifiedCompletionRequest.ContentString("Hello, world!"),
+            ROLE,
+            null,
+            null
+        );
+        var messageList = new ArrayList<UnifiedCompletionRequest.Message>();
+        messageList.add(message);
+
+        var unifiedRequest = UnifiedCompletionRequest.of(messageList);
+
+        UnifiedChatInput unifiedChatInput = new UnifiedChatInput(unifiedRequest, true);
+        LlamaChatCompletionModel model = LlamaChatCompletionModelTests.createChatCompletionModel("model", "url", "api-key");
+
+        LlamaChatCompletionRequestEntity entity = new LlamaChatCompletionRequestEntity(unifiedChatInput, model);
+
+        XContentBuilder builder = JsonXContent.contentBuilder();
+        entity.toXContent(builder, ToXContent.EMPTY_PARAMS);
+        String expectedJson = """
+            {
+                "messages": [{
+                        "content": "Hello, world!",
+                        "role": "user"
+                    }
+                ],
+                "model": "model",
+                "n": 1,
+                "stream": true,
+                "stream_options": {
+                    "include_usage": true
+                }
+            }
+            """;
+        assertEquals(XContentHelper.stripWhitespace(expectedJson), Strings.toString(builder));
+    }
+
+}