spring-boot - 在 Kotlin 中迁移到版本 3+ 时，Spring Boot 无法再绑定(bind)配置属性

Question

将应用迁移到 Spring Boot 3.0.1 后，无法再从 application.yml 文件加载配置属性。

它不适用于以前没问题的任何类。 以下配置规范开始失败，region 属性未初始化:

@ConfigurationProperties(prefix = "aws")
class AwsConfig {
    lateinit var region: Region
    var endpointUrl: URI? = null
}

我研究了更现代的实例化属性的方法，并得出以下结论:

package ...

import org.springframework.boot.context.properties.ConfigurationProperties
import org.springframework.boot.context.properties.bind.ConstructorBinding
import software.amazon.awssdk.regions.Region

@ConfigurationProperties(prefix = "aws")
data class AwsConfig @ConstructorBinding constructor(
    val region: Region
)

入口点注释如下:

@SpringBootApplication
@ConfigurationPropertiesScan
class Application

这现在会导致 NPE，让我相信这是一个读取级别的问题。有人遇到过这样的问题吗？

堆栈跟踪的根:

java.lang.IllegalStateException: Failed to load ApplicationContext for [WebMergedContextConfiguration@6fa1dc0c testClass = com.pkg.ApplicationContextTest, ...]
    at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:142)
...
Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'eventConsumerLauncher' defined in file ... Error creating bean with name 'aws-com.pkg.AwsConfig': Could not bind properties to 'AwsConfig' : prefix=aws, ignoreInvalidFields=false, ignoreUnknownFields=true
    at app//org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:798)
...
Caused by: org.springframework.boot.context.properties.ConfigurationPropertiesBindException: Error creating bean with name 'aws-com.pkg.AwsConfig': Could not bind properties to 'AwsConfig' : prefix=aws, ignoreInvalidFields=false, ignoreUnknownFields=true
    at app//org.springframework.boot.context.properties.ConstructorBound.from(ConstructorBound.java:46)
...
Caused by: org.springframework.boot.context.properties.bind.BindException: Failed to bind properties under 'aws' to com.pkg.AwsConfig
    at app//org.springframework.boot.context.properties.bind.Binder.handleBindError(Binder.java:387)
...
Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.pkg.AwsConfig]: Constructor threw exception
    at app//org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:223)
...
Caused by: java.lang.NullPointerException: Parameter specified as non-null is null: method com.pkg.AwsConfig.<init>, parameter region
    at com.pkg.AwsConfig.<init>(AwsConfig.kt)

有问题的 application.yml 文件如下所示:

server:
  port: -1

spring:
  config:
    activate:
      on-profile: integration

app:
  #...

aws:
  region: ${AWS_REGION:eu-west-1}

Answer 1

您很有可能受到此影响 issue ，对于 spring-boot 3.0.1 仍然开放。

您可以应用此问题下讨论的解决方法，或者等待可能在 spring-boot 3.0.2 中推出的解决方案。