feat(gemini-client): add GenerationConfig support

Introduce the GenerationConfig data class to configure text generation requests, including new properties such as temperature and responseMimeType. Additionally, add unit tests for GenerateContentRequest and GenerationConfig to ensure the correct serialization of these configurations.

Author: hanrw

gemini-client/gemini-client-core/src/commonMain/kotlin/com/tddworks/gemini/api/textGeneration/api/GenerateContentRequest.kt

@@ -28,6 +28,7 @@ data class GenerateContentRequest(
     @SerialName("system_instruction")
     val systemInstruction: Content? = null,
     val contents: List<Content>,
+    val generationConfig: GenerationConfig? = null,
     @Transient val model: GeminiModel = GeminiModel.GEMINI_1_5_FLASH,
     @Transient val stream: Boolean = false
 ) {

gemini-client/gemini-client-core/src/commonMain/kotlin/com/tddworks/gemini/api/textGeneration/api/GenerationConfig.kt

@@ -0,0 +1,33 @@
+package com.tddworks.gemini.api.textGeneration.api
+
+import kotlinx.serialization.SerialName
+import kotlinx.serialization.Serializable
+
+/**
+ * {
+ *   "contents": [{
+ *     "parts": [{
+ *       "text": "Write a story about a magic backpack."
+ *     }]
+ *   }],
+ *   "safetySettings": [{
+ *     "category": "HARM_CATEGORY_DANGEROUS_CONTENT",
+ *     "threshold": "BLOCK_ONLY_HIGH"
+ *   }],
+ *   "generationConfig": {
+ *     "stopSequences": [
+ *       "Title"
+ *     ],
+ *     "temperature": 1.0,
+ *     "response_mime_type": "application/json",
+ *     "maxOutputTokens": 800,
+ *     "topP": 0.8,
+ *     "topK": 10
+ *   }
+ * }
+ */
+@Serializable
+data class GenerationConfig(
+    val temperature: Float? = null,
+    @SerialName("response_mime_type") val responseMimeType: String? = null
+)

gemini-client/gemini-client-core/src/jvmTest/kotlin/com/tddworks/gemini/api/textGeneration/api/GenerateContentRequestTest.kt

@@ -9,6 +9,48 @@ import org.skyscreamer.jsonassert.JSONAssert
 
 class GenerateContentRequestTest {
 
+    @Test
+    fun `should return correct text request with response mime type`() {
+        // Given
+        val generateContentRequest = GenerateContentRequest(
+            contents = listOf(
+                Content(
+                    parts = listOf(
+                        Part.TextPart(text = "hello")
+                    )
+                )
+            ),
+            stream = false,
+            generationConfig = GenerationConfig(
+                responseMimeType = "application/json"
+            )
+        )
+
+        // When
+        val result = Json.encodeToString(
+            GenerateContentRequest.serializer(),
+            generateContentRequest
+        )
+
+        // Then
+        JSONAssert.assertEquals(
+            """
+            {
+                "contents": [{
+                    "parts": [{
+                        "text": "hello"
+                    }]
+                }],
+                "generationConfig": {
+                    "response_mime_type": "application/json"
+                }
+            }
+            """.trimIndent(),
+            result,
+            false
+        )
+    }
+
     @Test
     fun `should return correct text and image request`() {
 

gemini-client/gemini-client-core/src/jvmTest/kotlin/com/tddworks/gemini/api/textGeneration/api/GenerationConfigTest.kt

@@ -0,0 +1,35 @@
+package com.tddworks.gemini.api.textGeneration.api
+
+import kotlinx.serialization.json.Json
+import org.junit.jupiter.api.Test
+import org.skyscreamer.jsonassert.JSONAssert
+
+class GenerationConfigTest {
+
+    @Test
+    fun `should return correct generation config`() {
+        // Given
+        val generationConfig = GenerationConfig(
+            temperature = 1.0f,
+            responseMimeType = "application/json"
+        )
+
+        // When
+        val result = Json.encodeToString(
+            GenerationConfig.serializer(),
+            generationConfig
+        )
+
+        // Then
+        JSONAssert.assertEquals(
+            """
+            {
+                "temperature": 1.0,
+                "response_mime_type": "application/json"
+            }
+            """.trimIndent(),
+            result,
+            false
+        )
+    }
+}