Kotlin with Spring Boot 2.0 #ConfigurationProperties not working - spring-boot

Question

I'm building an application using Spring Boot 2 with Kotlin.
Somehow I just can't get ConfigurationProperties to work.
As far as I know when Maven compile is run then a file spring-configuration-metadata.json should be created in target/classes/META-INF
My setup so far:
pom.xml
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.brabantia.log</groupId>
<artifactId>logdb</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>logdb</name>
<description>Logging database Brabantia</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.0.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
<kotlin.version>1.2.21</kotlin.version>
<spring.boot.version>2.0.0.RELEASE</spring.boot.version>
</properties>
<dependencies><!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-starter -->
<!-- START SPRING BOOT DEPENDENCIES -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
<version>${spring.boot.version}</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
<version>${spring.boot.version}</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-security</artifactId>
<version>${spring.boot.version}</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
<version>${spring.boot.version}</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-configuration-processor</artifactId>
<version>${spring.boot.version}</version>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<version>${spring.boot.version}</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<version>${spring.boot.version}</version>
<scope>runtime</scope>
</dependency>
<!-- END SPRING BOOT DEPENDENCIES -->
<!-- START FLYWAY DEPENDENCIES -->
<dependency>
<groupId>org.flywaydb</groupId>
<artifactId>flyway-core</artifactId>
</dependency>
<!-- END FLYWAY DEPENDENCIES -->
<!-- START KOTLIN DEPENDENCIES -->
<dependency>
<groupId>org.jetbrains.kotlin</groupId>
<artifactId>kotlin-stdlib-jdk8</artifactId>
<version>1.2.30</version>
</dependency>
<dependency>
<groupId>org.jetbrains.kotlin</groupId>
<artifactId>kotlin-reflect</artifactId>
<version>1.2.30</version>
</dependency>
<!-- END KOTLIN DEPENDENCIES -->
<!-- START DATABASE DEPENDENCIES -->
<dependency>
<groupId>com.microsoft.sqlserver</groupId>
<artifactId>mssql-jdbc</artifactId>
<scope>runtime</scope>
</dependency>
<!-- END DATABASE DEPENDENCIES -->
</dependencies>
<build>
<sourceDirectory>${project.basedir}/src/main/kotlin</sourceDirectory>
<testSourceDirectory>${project.basedir}/src/test/kotlin</testSourceDirectory>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
<plugin>
<artifactId>kotlin-maven-plugin</artifactId>
<groupId>org.jetbrains.kotlin</groupId>
<configuration>
<args>
<arg>-Xjsr305=strict</arg>
</args>
<compilerPlugins>
<plugin>spring</plugin>
</compilerPlugins>
</configuration>
<dependencies>
<dependency>
<groupId>org.jetbrains.kotlin</groupId>
<artifactId>kotlin-maven-allopen</artifactId>
<version>${kotlin.version}</version>
</dependency>
</dependencies>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-surefire-plugin</artifactId>
</plugin>
<plugin>
<groupId>org.flywaydb</groupId>
<artifactId>flyway-maven-plugin</artifactId>
<version>5.0.7</version>
<configuration>
<user>esb_logging_user</user>
<password>esb_logging_user</password>
<url>jdbc:sqlserver://localhost;database=esb_logging</url>
</configuration>
</plugin>
</plugins>
</build>
</project>
LogDbProperties.kt
import org.springframework.boot.context.properties.ConfigurationProperties
import org.springframework.context.annotation.Configuration
#Configuration
#ConfigurationProperties(prefix = "logdb")
class LogDbProperties {
var enabled: Boolean = false
}
LogDbApplication.kt
import org.springframework.beans.factory.annotation.Autowired
import org.springframework.boot.CommandLineRunner
import org.springframework.boot.autoconfigure.SpringBootApplication
import org.springframework.boot.runApplication
#SpringBootApplication
class LogdbApplication: CommandLineRunner {
override fun run(vararg args: String?) {
println(logDbProperties.enabled)
}
#Autowired
lateinit var logDbProperties: LogDbProperties
}
fun main(args: Array<String>) {
runApplication<LogdbApplication>(*args)
}
How can I get this to work?
Update
It seems that the annotations are picked up by Spring, but IntelliJ just doesn't create the spring-configuration-metadata.json file, which means it's just autocompletions that's not working.
So how could I make IntelliJ create the spring-configuration-metadata.json file?

Answer 1

Thanks to this post on StackOverflow I finally have the answer
Just to make the solution complete:
Add the following dependency to pom.xml
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-configuration-processor</artifactId>
<optional>true</optional>
</dependency>
And (this is what all other answers are missing) add this execution to the kotlin-maven-plugin
<execution>
<id>kapt</id>
<goals>
<goal>kapt</goal>
</goals>
<configuration>
<sourceDirs>
<sourceDir>src/main/kotlin</sourceDir>
</sourceDirs>
<annotationProcessorPaths>
<annotationProcessorPath>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-configuration-processor</artifactId>
<version>1.5.3.RELEASE</version>
</annotationProcessorPath>
</annotationProcessorPaths>
</configuration>
</execution>
Now an example ConfigurationProperties class:
#ConfigurationProperties(prefix = "logdb")
class LogDbProperties {
var enabled: Boolean = false
}
Now run mvn compile or mvn clean compile
And presto: you have a file named spring-configuration-metadata.json in target/classes/META-INF.

Answer 2

Please see official Spring documentation regarding to configuration properties generation.
Shortly, you have to add this into maven:
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-configuration-processor</artifactId>
<optional>true</optional>
</dependency>
Important: IntelliJ idea could not work with kapt, which will generate metadata. So you have to ask gradle/maven to make a full build. As a result:
Your output folders will have spring-configuration-metadata.json generated.
Your output jar will have this file too
IntelliJ Idea will read this file and will show highlights.