想出了解决办法。除了 application.properties 配置之外，我还必须创建一个配置类，当提供适当的凭证时，它可以让我访问 AmazonS3Client 对象。我在 GitHub 上遵循了这个示例：
https://github.com/brant-hwang/spring-cloud-aws-example/blob/master/src/main/java/com/axisj/spring/cloud/aws/AWSConfiguration.java
AWSConfiguration.java：
import com.amazonaws.auth.AWSCredentials;
import com.amazonaws.auth.BasicAWSCredentials;
import com.amazonaws.regions.Region;
import com.amazonaws.regions.Regions;
import com.amazonaws.services.s3.AmazonS3Client;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
@Configuration
public class AWSConfiguration {
@Value("${cloud.aws.credentials.accessKey}")
private String accessKey;
@Value("${cloud.aws.credentials.secretKey}")
private String secretKey;
@Value("${cloud.aws.region}")
private String region;
@Bean
public BasicAWSCredentials basicAWSCredentials() {
return new BasicAWSCredentials(accessKey, secretKey);
}
@Bean
public AmazonS3Client amazonS3Client(AWSCredentials awsCredentials) {
AmazonS3Client amazonS3Client = new AmazonS3Client(awsCredentials);
amazonS3Client.setRegion(Region.getRegion(Regions.fromName(region)));
return amazonS3Client;
}
}
配置完成后，您可以在其他类中创建 AmazonS3Client 对象（自动装配），并使用客户端向您的 S3 云发出请求。该示例使用包装类作为服务，以简化其他控制器类的实现。
S3Wrapper.java：
import com.amazonaws.services.s3.AmazonS3Client;
import com.amazonaws.services.s3.model.*;
import org.apache.commons.io.IOUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.stereotype.Service;
import org.springframework.util.StringUtils;
import org.springframework.web.multipart.MultipartFile;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
@Service
public class S3Wrapper {
@Autowired
private AmazonS3Client amazonS3Client;
@Value("${cloud.aws.s3.bucket}")
private String bucket;
private PutObjectResult upload(String filePath, String uploadKey) throws FileNotFoundException {
return upload(new FileInputStream(filePath), uploadKey);
}
private PutObjectResult upload(InputStream inputStream, String uploadKey) {
PutObjectRequest putObjectRequest = new PutObjectRequest(bucket, uploadKey, inputStream, new ObjectMetadata());
putObjectRequest.setCannedAcl(CannedAccessControlList.PublicRead);
PutObjectResult putObjectResult = amazonS3Client.putObject(putObjectRequest);
IOUtils.closeQuietly(inputStream);
return putObjectResult;
}
public List<PutObjectResult> upload(MultipartFile[] multipartFiles) {
List<PutObjectResult> putObjectResults = new ArrayList<>();
Arrays.stream(multipartFiles)
.filter(multipartFile -> !StringUtils.isEmpty(multipartFile.getOriginalFilename()))
.forEach(multipartFile -> {
try {
putObjectResults.add(upload(multipartFile.getInputStream(), multipartFile.getOriginalFilename()));
} catch (IOException e) {
e.printStackTrace();
}
});
return putObjectResults;
}
public ResponseEntity<byte[]> download(String key) throws IOException {
GetObjectRequest getObjectRequest = new GetObjectRequest(bucket, key);
S3Object s3Object = amazonS3Client.getObject(getObjectRequest);
S3ObjectInputStream objectInputStream = s3Object.getObjectContent();
byte[] bytes = IOUtils.toByteArray(objectInputStream);
String fileName = URLEncoder.encode(key, "UTF-8").replaceAll("\\+", "%20");
HttpHeaders httpHeaders = new HttpHeaders();
httpHeaders.setContentType(MediaType.APPLICATION_OCTET_STREAM);
httpHeaders.setContentLength(bytes.length);
httpHeaders.setContentDispositionFormData("attachment", fileName);
return new ResponseEntity<>(bytes, httpHeaders, HttpStatus.OK);
}
public List<S3ObjectSummary> list() {
ObjectListing objectListing = amazonS3Client.listObjects(new ListObjectsRequest().withBucketName(bucket));
List<S3ObjectSummary> s3ObjectSummaries = objectListing.getObjectSummaries();
return s3ObjectSummaries;
}
}
注意：需要将以下依赖项添加到 pom.xml 才能使用 Apache Commons IO 库。
pom.xml：
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-io</artifactId>
<version>1.3.2</version>
</dependency>