Kotlin updates (spring-projects#2006)

* Update Kotlin documentation

This commit updates the Kotlin documentation to
showcase the new Kotlin reflection capabilities
allowing to identify required properties.

* Update Kotlin integration tests

This commit updates the Kotlin integration tests to
leverage the new Kotlin reflection capabilities
allowing to identify required properties.

It also adds a missing jackson-module-kotlin
dependency and refine test implementation to be
closer to the Java ones and use more idiomatic
Kotlin code.

Signed-off-by: leijendary <[email protected]>

Author: sdeleuze

spring-ai-docs/src/main/antora/modules/ROOT/pages/api/chat/openai-chat.adoc

@@ -376,14 +376,14 @@ Kotlin::
 [source,kotlin]
 ----
 data class MathReasoning(
-	@get:JsonProperty(required = true, value = "steps") val steps: Steps,
-	@get:JsonProperty(required = true, value = "final_answer") val finalAnswer: String) {
+	val steps: Steps,
+	@get:JsonProperty(value = "final_answer") val finalAnswer: String) {
 
-	data class Steps(@get:JsonProperty(required = true, value = "items") val items: Array<Items>) {
+	data class Steps(val items: Array<Items>) {
 
 		data class Items(
-			@get:JsonProperty(required = true, value = "explanation") val explanation: String,
-			@get:JsonProperty(required = true, value = "output") val output: String)
+			val explanation: String,
+			val output: String)
 	}
 }
 
@@ -405,9 +405,7 @@ val mathReasoning = outputConverter.convert(content)
 ======
 --
 
-NOTE: Ensure you use the `@JsonProperty(required = true,...)`  annotation (`@get:JsonProperty(required = true,...)` with Kotlin in order to generate the annotation on the related getters, see link:https://kotlinlang.org/docs/annotations.html#annotation-use-site-targets[related documentation]).
-This is crucial for generating a schema that accurately marks fields as `required`. 
-Although this is optional for JSON Schema, OpenAI link:https://platform.openai.com/docs/guides/structured-outputs/all-fields-must-be-required[mandates] it for the structured response to function correctly.
+NOTE: Although this is optional for JSON Schema, OpenAI link:https://platform.openai.com/docs/guides/structured-outputs/all-fields-must-be-required#all-fields-must-be-required[mandates] required fields for the structured response to function correctly. Kotlin reflection is used to infer which property are required or not based on the nullability of types and default values of parameters, so for most use case `@get:JsonProperty(required = true)` is not needed. `@get:JsonProperty(value = "custom_name")` can be useful to customize the property name. Make sure to generate the annotation on the related getters with this `@get:` syntax, see link:https://kotlinlang.org/docs/annotations.html#annotation-use-site-targets[related documentation].
 
 ==== Configuring via Application Properties
 

spring-ai-spring-boot-autoconfigure/pom.xml

@@ -586,6 +586,12 @@
 			<scope>test</scope>
 		</dependency>
 
+		<dependency>
+			<groupId>com.fasterxml.jackson.module</groupId>
+			<artifactId>jackson-module-kotlin</artifactId>
+			<scope>test</scope>
+		</dependency>
+
 	</dependencies>
 
 </project>

spring-ai-spring-boot-autoconfigure/src/test/kotlin/org/springframework/ai/autoconfigure/ollama/tool/FunctionCallbackContextKotlinIT.kt

@@ -39,7 +39,7 @@ class FunctionCallbackResolverKotlinIT : BaseOllamaIT() {
 
 	companion object {
 
-		private val MODEL_NAME = OllamaModel.LLAMA3_2.getName();
+		private val MODEL_NAME = "qwen2.5:3b";
 
 		@JvmStatic
 		@BeforeAll
@@ -72,7 +72,7 @@ class FunctionCallbackResolverKotlinIT : BaseOllamaIT() {
 			val response = chatModel
 					.call(Prompt(listOf(userMessage), OllamaOptions.builder().function("weatherInfo").build()))
 
-			logger.info("Response: " + response)
+			logger.info("Response: $response")
 
 			assertThat(response.getResult().output.text).contains("30", "10", "15")
 		}
@@ -93,10 +93,11 @@ class FunctionCallbackResolverKotlinIT : BaseOllamaIT() {
 				.build()
 
 			val response = chatModel.call(Prompt(listOf(userMessage), functionOptions));
+			val output = response.getResult().output.text
 
-			logger.info("Response: " + response.getResult().getOutput().getText());
+			logger.info("Response: $output");
 
-			assertThat(response.getResult().output.text).contains("30", "10", "15");
+			assertThat(output).contains("30", "10", "15");
 		}
 	}
 

spring-ai-spring-boot-autoconfigure/src/test/kotlin/org/springframework/ai/autoconfigure/ollama/tool/FunctionCallbackKotlinIT.kt

@@ -28,7 +28,6 @@ import org.springframework.ai.chat.prompt.Prompt
 import org.springframework.ai.model.function.FunctionCallback
 import org.springframework.ai.model.function.FunctionCallingOptions
 import org.springframework.ai.ollama.OllamaChatModel
-import org.springframework.ai.ollama.api.OllamaModel
 import org.springframework.ai.ollama.api.OllamaOptions
 import org.springframework.boot.autoconfigure.AutoConfigurations
 import org.springframework.boot.test.context.runner.ApplicationContextRunner
@@ -39,7 +38,7 @@ class FunctionCallbackKotlinIT : BaseOllamaIT() {
 
 	companion object {
 
-		private val MODEL_NAME = OllamaModel.LLAMA3_2.getName();
+		private val MODEL_NAME = "qwen2.5:3b";
 
 		@JvmStatic
 		@BeforeAll
@@ -72,7 +71,7 @@ class FunctionCallbackKotlinIT : BaseOllamaIT() {
 			val response = chatModel
 					.call(Prompt(listOf(userMessage), OllamaOptions.builder().function("WeatherInfo").build()))
 
-			logger.info("Response: " + response)
+			logger.info("Response: $response")
 
 			assertThat(response.getResult().output.text).contains("30", "10", "15")
 		}
@@ -93,10 +92,10 @@ class FunctionCallbackKotlinIT : BaseOllamaIT() {
 				.build()
 
 			val response = chatModel.call(Prompt(listOf(userMessage), functionOptions));
+			val output = response.getResult().output.text
+			logger.info("Response: $output");
 
-			logger.info("Response: " + response.getResult().getOutput().getText());
-
-			assertThat(response.getResult().output.text).contains("30", "10", "15");
+			assertThat(output).contains("30", "10", "15");
 		}
 	}
 

spring-ai-spring-boot-autoconfigure/src/test/kotlin/org/springframework/ai/autoconfigure/ollama/tool/MockKotlinWeatherService.kt

@@ -61,19 +61,16 @@ enum class Unit(val unitName: String) {
 @JsonInclude(Include.NON_NULL)
 @JsonClassDescription("Weather API request")
 data class KotlinRequest(
-	@get:JsonProperty(required = true, value = "location")
+
 	@get:JsonPropertyDescription("The city and state e.g. San Francisco, CA")
-	val location: String = "",
+	val location: String,
 
-	@get:JsonProperty(required = true, value = "lat")
 	@get:JsonPropertyDescription("The city latitude")
-	val lat: Double = 0.0,
+	val lat: Double,
 
-	@get:JsonProperty(required = true, value = "lon")
 	@get:JsonPropertyDescription("The city longitude")
-	val lon: Double = 0.0,
+	val lon: Double,
 
-	@get:JsonProperty(required = true, value = "unit")
 	@get:JsonPropertyDescription("Temperature unit")
 	val unit: Unit = Unit.C
 )