aws s3 预签名上传文件,下载文件

需求是生成预签名下载链接，将链接发送给没有s3权限的用户，其也能正常下载而不需要登录到aws。
上传也是同理，生成预签名上传链接，用户上传时无需登录aws。

1.引入jar包

    <dependency>
        <groupId>software.amazon.awssdk</groupId>
        <artifactId>bom</artifactId>
        <version>2.17.24</version>
        <type>pom</type>
        <scope>import</scope>
    </dependency>


 <dependency>
    <groupId>software.amazon.awssdk</groupId>
    <artifactId>s3</artifactId>
</dependency>

2. 下载文件，上传文件，判断文件是否存在，读取文件

package test.util;

import org.apache.commons.lang3.StringUtils;
import org.springframework.stereotype.Service;
import org.springframework.util.Assert;
import org.springframework.web.util.UriComponents;
import org.springframework.web.util.UriComponentsBuilder;
import software.amazon.awssdk.auth.credentials.InstanceProfileCredentialsProvider;
import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.s3.S3Client;
import software.amazon.awssdk.services.s3.internal.presigner.DefaultS3Presigner;
import software.amazon.awssdk.services.s3.model.GetObjectRequest;
import software.amazon.awssdk.services.s3.model.HeadObjectRequest;
import software.amazon.awssdk.services.s3.model.HeadObjectResponse;
import software.amazon.awssdk.services.s3.model.NoSuchKeyException;
import software.amazon.awssdk.services.s3.model.PutObjectRequest;
import software.amazon.awssdk.services.s3.presigner.S3Presigner;
import software.amazon.awssdk.services.s3.presigner.model.PresignedGetObjectRequest;
import software.amazon.awssdk.services.s3.presigner.model.PresignedPutObjectRequest;
import software.amazon.awssdk.services.s3.presigner.model.PutObjectPresignRequest;

import javax.annotation.Resource;
import java.io.InputStream;
import java.time.Duration;
import java.util.Objects;

@Service
public class S3Utils {

    static S3Presigner s3Presigner;
    static S3Client s3Client;

    @Resource
    ReconFeature reconFeature;

    static {
        s3Presigner = DefaultS3Presigner
                .builder()
                .region(Region.AP_SOUTH_1)
                .credentialsProvider(InstanceProfileCredentialsProvider.create())
                .build();

        s3Client = S3Client.builder()
                .region(Region.AP_SOUTH_1)
                .credentialsProvider(InstanceProfileCredentialsProvider.create())
                .build();
    }

    /* 生成下载文件的预签名地址
     * s3Path = s3://bucket/a/b/c/
     * fileName = 123.txt
     * effectiveDay = 有效期
     */
    public static String signGetObject(String s3Path, String fileName, int effectiveDay) {
        UriComponents build = UriComponentsBuilder.fromUriString(s3Path)
                .path("/")
                .path(fileName)
                .build();
        String bucket = build.getHost();
        String key = build.getPath();
        Assert.notNull(key, "can not singFile for s3Path:" + s3Path + " fileName:" + fileName);

        if (key.startsWith("/")) {
            key = key.substring(1);
        }
        GetObjectRequest request = GetObjectRequest.builder()
                .bucket(bucket)
                .key(key)
                .build();
        PresignedGetObjectRequest presignedGetObjectRequest = s3Presigner.presignGetObject(b -> {
            b.getObjectRequest(request);
            b.signatureDuration(Duration.ofDays(effectiveDay));
        });
        return presignedGetObjectRequest.url().toString();
    }



    /* 生成上传文件的预签名地址
     * s3FullPath = s3://bucket/a/b/c/123.txt
     */
    public static String signPutObject(String s3FullPath) {
        Assert.isTrue(s3FullPath.startsWith("s3://"), "s3全路径不正确");
        UriComponents build = UriComponentsBuilder.fromUriString(s3FullPath)
                .build();
        String bucket = build.getHost();
        String key = build.getPath().substring(1);

        PutObjectRequest request = PutObjectRequest.builder()
                .bucket(bucket)
                .key(key)
                .build();
        PutObjectPresignRequest preRequest = PutObjectPresignRequest.builder()
                .signatureDuration(Duration.ofMinutes(15))
                .putObjectRequest(request)
                .build();
        PresignedPutObjectRequest presignedPutObjectRequest = s3Presigner.presignPutObject(preRequest);

        return presignedPutObjectRequest.url().toString();
    }
    
    /*
     *判断文件是否存在在s3上
     */
    public static HeadObjectResponse fileExist(String s3Path, String fileName) {
        UriComponents build = UriComponentsBuilder.fromUriString(s3Path)
                .path(fileName)
                .build();
        String key = Objects.requireNonNull(build.getPath()).substring(1);

        HeadObjectRequest req = HeadObjectRequest.builder()
                .bucket(build.getHost())
                .key(key)
                .build();
        try {
            return s3Client.headObject(req);
        } catch (NoSuchKeyException e) {
            return null;
        }
    }

    /*
     * 读取s3的文件，以文件流形式返回（注意使用完一定要关闭流，否则会导致连接池连接占用完）
     */
    public static InputStream readFile(String s3Path, String fileName) {
        UriComponents build = UriComponentsBuilder.fromUriString(s3Path)
                .path(fileName)
                .build();
        String key = Objects.requireNonNull(build.getPath()).substring(1);

        GetObjectRequest req = GetObjectRequest.builder()
                .bucket(build.getHost())
                .key(key)
                .build();
        return s3Client.getObject(req);
    }

}