java - 将 SpringCloud Finchley 升级到 RELEASE 时缺少 AmazonS3Client Bean

Question

我最近将我的 SpringCloud 项目从 Brixton 升级到 Finchley，一切工作正常。我正在开发 Finchley.SR2，没有遇到任何问题，但每当我将项目升级到 Finchley.RELEASE(这是我所做的唯一更改)时，项目就无法启动。

原因是项目找不到AmazonS3Client Bean:

...Unsatisfied dependency expressed through constructor parameter 0; 
nested exception is 
  org.springframework.beans.factory.NoSuchBeanDefinitionException: 
    No qualifying bean of type 'com.amazonaws.services.s3.AmazonS3Client' available: 
      expected at least 1 bean which qualifies as autowire candidate. 
        Dependency annotations: {}

这些是我之前的相关配置和类:

build.gradle

buildscript {
    ext {
        springBootVersion = '2.0.2.RELEASE'
    }

    ...

    dependencies {
        classpath("org.springframework.boot:spring-boot-gradle-plugin:${springBootVersion}")
        classpath('io.spring.gradle:dependency-management-plugin:1.0.5.RELEASE')
    }
}

apply plugin: 'java'
apply plugin: 'org.springframework.boot'
apply plugin: 'io.spring.dependency-management'
    
dependencyManagement {
    imports {
        mavenBom "org.springframework.cloud:spring-cloud-dependencies:Finchley.SR2"
    }
}

dependencies {
    ...
    compile('org.springframework.boot:spring-boot-starter-web')
    compile('org.springframework.cloud:spring-cloud-starter-aws')
    compile('org.springframework.cloud:spring-cloud-starter-config'
    ...
}

...

S3Config.java(创建 AmazonS3/AmazonS3Client Bean 的类)

...

@Configuration
public class S3Config {

    @Bean
    public AmazonS3 amazonS3() {
        return AmazonS3ClientBuilder.standard()
                .withCredentials(new DefaultAWSCredentialsProviderChain())
                .build();
    }
}

StorageService(找不到Bean的类)

...

@Service
public class StorageService {

    private final AmazonS3Client amazonS3Client;

    @Autowired
    public StorageService(AmazonS3Client amazonS3Client) {
        this.amazonS3Client = amazonS3Client;
    }

    ...
}

这是我升级到 Finchley.Release 时对 build.gradle 文件所做的唯一更改:

dependencyManagement {
    imports {
        mavenBom "org.springframework.cloud:spring-cloud-dependencies:Finchley.RELEASE"
    }
}

我尝试寻找任何丢失的库并调整我能找到的所有配置，但似乎没有任何效果。

Answer 1

与 Spring 维护者进行简短交谈后，a solution was found .

看来我的错误是假设 AmazonS3 的 Bean 应该始终作为 AmazonS3Client Bean 找到，只是因为其中一个实现了另一个。它能在以前的 Spring 版本上运行纯属运气。

创建 AmazonS3Client 的正确方法如下:

@Configuration
public class S3Config {

    @Bean
    public static AmazonS3Client amazonS3Client() {
        return (AmazonS3Client) AmazonS3ClientBuilder.standard()
                .withCredentials(new DefaultAWSCredentialsProviderChain())
                .build();
    }
}