生成预签名URL

生成预签名下载链接

您可以利用 GeneratePresignedUrl 接口为一个对象生成一个预签名的URL链接。通过访问该链接即可下载该对象。

String bucketName = "<your-bucket-name>";
String objectKey = "<your-object-key>";
try {
    GeneratePresignedUrlRequest request = new GeneratePresignedUrlRequest(bucketName, objectKey)
            .withMethod(HttpMethod.GET)
            .withExpiration(expiration);
    URL url = s3.generatePresignedUrl(request);
} catch (AmazonServiceException e) {
    System.err.println(e.getErrorMessage());
}

如果需要在URL中添加额外参数，可以使用addRequestParameter接口

String bucketName = "<your-bucket-name>";
String objectKey = "<your-object-key>";
try {
    GeneratePresignedUrlRequest request = new GeneratePresignedUrlRequest(bucketName, objectKey)
            .withMethod(HttpMethod.GET)
            .withExpiration(expiration);
    // 在URL中添加额外参数
    request.addRequestParameter("x-amz-limit", String.format("rate=%d", 100));
    request.addRequestParameter("x-amz-process", "image/watermark,text_12345678");
    URL url = s3.generatePresignedUrl(request);
} catch (AmazonServiceException e) {
    System.err.println(e.getErrorMessage());
}

生成预签名上传链接

您可以利用 GeneratePresignedUrl 接口为一个对象生成一个预签名的URL链接，通过该链接可上传对象。

String bucketName = "<your-bucket-name>";
String objectKey = "<your-object-key>";
LocalDateTime expirationDateTime = LocalDateTime.now().plusSeconds(5 * 60);//url的有效时间5分钟
Date expiration = Date.from(expirationDateTime.atZone(ZoneId.systemDefault()).toInstant());
try {
    GeneratePresignedUrlRequest generatePresignedUrlRequest = new GeneratePresignedUrlRequest(bucketName, objectKey)
            .withMethod(HttpMethod.PUT)
            .withExpiration(expiration);
    URL url = s3.generatePresignedUrl(generatePresignedUrlRequest);
} catch (AmazonServiceException e) {
    System.err.println(e.getErrorMessage());
}

参数如下，

参数	类型	描述
bucketName	String	桶名
key	String	对象名
expiration	Date	过期时间，默认900秒