Spring Boot+AWS SDK v2项目s3Config Bean创建失败求助

问题描述 #

基于Java 17、Maven开发Spring Boot项目，整合AWS SDK v2时启动抛出以下错误：

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 's3Config': Injection of autowired dependencies failed

相关代码与配置 #

DemoApplication.java #

package com.example.demo;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class DemoApplication {

    public static void main(String[] args) {
        SpringApplication.run(DemoApplication.class, args);
    }

}

S3Config.java #

package com.example.demo.config;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import software.amazon.awssdk.auth.credentials.AwsBasicCredentials;
import software.amazon.awssdk.auth.credentials.StaticCredentialsProvider;
import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.s3.S3Client;

@Configuration
public class S3Config {
    @Value("${region}")
    private String region;

    @Value("${accessKey}")
    private String accessKey;

    @Value("${secretKey}")
    private String secretKey;

    @Bean
    S3Client s3Client() {
        AwsBasicCredentials credentials = AwsBasicCredentials.create(accessKey, secretKey);
        return S3Client.builder()
                .credentialsProvider(StaticCredentialsProvider.create(credentials))
                .region(Region.of(region))
                .build();
    }
}

S3Controller.java #

package com.example.demo.controller;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.GetMapping;

import com.example.demo.services.S3Service;

public class S3Controller {
    
    @Autowired
    private S3Service s3Service;
    @GetMapping("/listAllObjects")
    public ResponseEntity<List<String>> viewObjects() {
        return new ResponseEntity<>(s3Service.listObjects(),HttpStatus.OK);
    }
}

S3Service.java #

package com.example.demo.services;


import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Service;
import software.amazon.awssdk.services.s3.S3Client;
import software.amazon.awssdk.services.s3.model.ListObjectsResponse;
import software.amazon.awssdk.services.s3.model.S3Object;
import java.util.List;
import java.util.stream.Collectors;

@Service
public class S3Service {
    @Value("${bucketName}")
    private String bucketName;

    private final S3Client s3Client;

    public S3Service(S3Client s3Client) {
        this.s3Client = s3Client;
    }

    public List<String> listObjects() {
        ListObjectsResponse listObjectsResponse = s3Client.listObjects(b -> b.bucket(bucketName));
        return listObjectsResponse.contents().stream()
                .map(S3Object::key)
                .collect(Collectors.toList());
    }
}

application.properties #

spring.application.name=demo
aws.region=`${region}`
aws.accessKey=`${accessKey}`
aws.secretKey=`${secretKey}`
aws.bucketName=`${bucketName}`
spring.autoconfigure.exclude=org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration

修复方案 #

1. 修正配置键名不匹配问题 #

S3Config和S3Service中@Value注解引用的键名，与application.properties中的实际键名不一致，导致Spring无法注入属性。

修改S3Config：

@Value("${aws.region}")
private String region;

@Value("${aws.accessKey}")
private String accessKey;

@Value("${aws.secretKey}")
private String secretKey;

修改S3Service：

@Value("${aws.bucketName}")
private String bucketName;

2. 修复配置文件变量格式错误 #

application.properties中使用了反引号包裹环境变量，这会导致Spring无法正确解析，需去掉反引号：

spring.application.name=demo
aws.region=${region}
aws.accessKey=${accessKey}
aws.secretKey=${secretKey}
aws.bucketName=${bucketName}
spring.autoconfigure.exclude=org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration

如果不需要读取环境变量，直接填写实际AWS配置值即可，例如：

spring.application.name=demo
aws.region=us-east-1
aws.accessKey=你的AWS访问密钥
aws.secretKey=你的AWS秘密密钥
aws.bucketName=你的S3存储桶名称
spring.autoconfigure.exclude=org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration

3. 补充控制器注解 #

S3Controller缺少@RestController注解，Spring无法识别为控制器Bean，需添加：

@RestController
public class S3Controller {
    // 原有代码不变
}

4. 确认依赖完整性 #

确保pom.xml中已引入正确的AWS SDK v2和Spring Boot依赖：

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <dependency>
        <groupId>software.amazon.awssdk</groupId>
        <artifactId>s3</artifactId>
        <version>2.20.0</version> <!-- 使用最新稳定版本 -->
    </dependency>
</dependencies>

内容的提问来源于stack exchange，提问作者Aswin Shaji