Amazon S3 的 java sdk简单使用

Amazon S3 的 java sdk简单使用

在开发过程中基本都需要使用到对象存储技术。

对于一些国内的项目来说，可以使用阿里云，七牛云，京东云等开发平台进行开发对接存储对象。

而对于海外的项目，可能现有的国内技术无法使用，这时候就遇到了amazon这个平台了。在此只整理了其对接以及对象存储和验签预览对象的功能。

以下使用的是AWS SDK for Java2.x的开发工具包

详细使用请看：https://github.com/aws/aws-sdk-java-v2/#using-the-sdk

一、项目依赖导入

maven依赖管理

<dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>software.amazon.awssdk</groupId>
            <artifactId>bom</artifactId>
            <version>2.17.100</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>
    </dependencies>
</dependencyManagement>

选择需要的模块进行依赖

<dependencies>
    <!--amazon s3-->
    <dependency>
        <groupId>software.amazon.awssdk</groupId>
        <artifactId>s3</artifactId>
    </dependency>
    <dependency>
        <groupId>software.amazon.awssdk</groupId>
        <artifactId>kms</artifactId>
    </dependency>
    <dependency>
        <groupId>software.amazon.awssdk</groupId>
        <artifactId>s3control</artifactId>
    </dependency>
</dependencies>

整个SDK包(不建议使用此方式导入，有大量的不需要的模块)：

<dependency>
  <groupId>software.amazon.awssdk</groupId>
  <artifactId>aws-sdk-java</artifactId>
  <version>2.17.100</version>
</dependency>

二、配置添加

nacos：

aws:
  s3:
    accessKey: xxxxxxxxxx
    secretKey: xxxxxxxxxx
    region: us-east-2 (选择s3控制台上的资源区域)
    bucket: xxx

配置类读取nacos的配置：

/**
 * @author Survivor
 * @create 2021/12/20 17:49
 */
@Configuration
public class AwsConfiguration {
    
    

    @Value("${aws.s3.accessKey}")
    private String accessKey;
    @Value("${aws.s3.secretKey}")
    private String secretKey;
    @Value("${aws.s3.region}")
    private String region;
    @Value("${aws.s3.bucket}")
    private String bucket;

    @Bean
    public void initAwConfiguration() {
    
    
        AwsUtils.setAccessKey(accessKey);
        AwsUtils.setSecretKey(secretKey);
        AwsUtils.setRegion(region);
        AwsUtils.setBucket(bucket);
    }
}

获取配置：

/**
 * @author Survivor
 * @create 2021/12/20 17:48
 */
@Slf4j
public class AwsUtils {
    
    

    private static String accessKey;
    private static String secretKey;
    private static String region;

    //  bucket
    private static String bucket;

    public static void setAccessKey(String accessKey) {
    
    
        AwsUtils.accessKey = accessKey;
    }

    public static void setSecretKey(String secretKey) {
    
    
        AwsUtils.secretKey = secretKey;
    }

    public static void setBucket(String bucket) {
    
    
        AwsUtils.bucket = bucket;
    }
    
    public static void setRegion(String region) {
    
    
        AwsUtils.region = region;
    }
}

三、使用aws的s3 SDK

1. 获取s3对象

/**
 * 获取S3Client对象
 *
 * @return s3
 */
private static S3Client getAmazonS3() {
    
    
    return S3Client.builder()
            .credentialsProvider(getAwsCredentialsProviderChain())
            .region(Region.of(region))
            .build();
}

// 获取aws供应商凭据
private static AwsCredentialsProviderChain getAwsCredentialsProviderChain(){
    
    
    return AwsCredentialsProviderChain
        .builder()
        .addCredentialsProvider(new AwsCredentialsProvider() {
    
    
            @Override
            public AwsCredentials resolveCredentials() {
    
    
                return AwsBasicCredentials.create(accessKey, secretKey);
            }
        }).build();
}

2. 对象存储

private static String putS3Object(S3Client s3, String bucketName, String objectKey, String objectPath) {
    
    
    try {
    
    
        String mimetype = Mimetypes.getInstance().getMimetype(new File(objectPath));
        PutObjectRequest putOb = PutObjectRequest.builder()
                .bucket(bucketName)
                .key(objectKey)
                .contentType(mimetype)
                .build();
        PutObjectResponse response = s3.putObject(putOb, RequestBody.fromBytes(getObjectFile(objectPath)));
        return response.eTag();
    } catch (S3Exception e) {
    
    
        System.err.println(e.getMessage());
        System.exit(1);
    }
    return "";
}

private static byte[] getObjectFile(String filePath) {
    
    
    FileInputStream fileInputStream = null;
    byte[] bytesArray = null;
    try {
    
    
        File file = new File(filePath);
        bytesArray = new byte[(int) file.length()];
        fileInputStream = new FileInputStream(file);
        fileInputStream.read(bytesArray);
    } catch (IOException e) {
    
    
        e.printStackTrace();
    } finally {
    
    
        if (fileInputStream != null) {
    
    
            try {
    
    
                fileInputStream.close();
            } catch (IOException e) {
    
    
                e.printStackTrace();
            }
        }
    }
    return bytesArray;
}

​ putS3Object()方法返回的字符串信息，就是上传后的存储key，如果你的存储的bucket不是私有的，可以直接拼接域名，直接访问bucket上的对象。但如果你的bucket是私有的，又想要访问其对象的话，就需要用到下面的验签获取：

对象获取

private static S3Presigner getS3Presigner() {
    
    
    return  S3Presigner.builder()
        .region(Region.of(region))
        .credentialsProvider(getAwsCredentialsProviderChain())
        .build();
}

/**
 * 预览 有效时间为1小时
 *
 * @param key
 * @return
 */
private static String preview(String bucketName, String key) {
    
    
    GetObjectRequest getObjectRequest =
        GetObjectRequest.builder()
        .bucket(bucketName)
        .key(key)
        .build();

    GetObjectPresignRequest getObjectPresignRequest =  GetObjectPresignRequest.builder()
        .signatureDuration(Duration.ofMinutes(60))
        .getObjectRequest(getObjectRequest)
        .build();

    PresignedGetObjectRequest presignedGetObjectRequest =
        getS3Presigner().presignGetObject(getObjectPresignRequest);

    return presignedGetObjectRequest.url().toString();
}

得到的是一串加上了验签参数的url路径，得到这个路径后就可以直接访问了。

这边只整理了小部分功能，其余的功能有需要的可以参考官方代码示例：https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javav2/example_code/s3/src/main/java/com/example/s3