如何检查 AWS S3 中是否已存在存储桶

Question

How can I check if the bucket already exists in my Aws S3 account using Java SDK?

Using below code

        AmazonS3ClientBuilder.defaultClient().doesBucketExistV2(bucketName);

Checks global existence of bucket and returns true if a bucket with this name exists globally even if I am not the owner of this bucket or I don't have access to that bucket.

I understand the intent for making this method this way so that It allows us to determine the availability of bucket name but this is not what I need. Of course, it will throw exception that I don't have access to it later, but it returns stating that bucket with this name exists.

I want to check if the bucket with the given name exists in my S3 account so that I can perform operations on it.

One possible solution for it can be to list all the buckets and search for my bucket in that returned list which I feel is not a good performance-wise (correct me if I am wrong) as there can be hundreds of thousands of buckets and searching in them is not efficient.

How can I determine if a bucket exists in my S3 account not checking global existence ?

Answer 1

as mentioned in the comments headBucket does the job.

HeadBucketRequest headBucketRequest = HeadBucketRequest.builder()
            .bucket(bucketName)
            .build();

    try {
        s3Client.headBucket(headBucketRequest);
        return true;
    } catch (NoSuchBucketException e) {
        return false;
    }

Answer 2

SDK 1.x does not have a HeadBucketRequest builder nor a NoSuchBucketException .

In case anyone is looking for the answer using AWS SDK for Java 1.x , this works:

private boolean checkAccessToBucket(final String bucketName) {
    try {
        final HeadBucketRequest request = new HeadBucketRequest(bucketName);
        s3Client.headBucket(request);
        return true;
    } catch (AmazonServiceException ex) {
        if (ex.getStatusCode() == 404 | ex.getStatusCode() == 403 || ex.getStatusCode() == 301) {
            return false;
        }
        throw ex;
    } catch (Exception ex) {
        LOGGER.error("Cannot check access", ex);
        throw ex;
    }
}