Question

How do I use AWS SDK for ASP.NET to upload a file to a specific folder? – I was able to upload files by specifying the bucket name (request.WithBucketName), but I want to be able to upload a file to a specific folder within the bucket itself.

This is the code that I use to upload a file to a single bucket:

public bool UploadFileToS3(string uploadAsFileName, Stream ImageStream, S3CannedACL filePermission, S3StorageClass storageType, string toWhichBucketName)
{

    try
    {
        client = Amazon.AWSClientFactory.CreateAmazonS3Client(MY_AWS_ACCESS_KEY_ID, MY_AWS_SECRET_KEY);
        PutObjectRequest request = new PutObjectRequest();
        request.WithKey(uploadAsFileName);
        request.WithInputStream(ImageStream);
        request.WithBucketName(toWhichBucketName);
        request.CannedACL = filePermission;
        request.StorageClass = storageType;

        client.PutObject(request);
        client.Dispose();
    }
    catch
    {            
        return false;
    }
    return true;

}

Hope that this code will help you out.

Answer 1

To add a file to a folder in a bucket, you need to update the Key of the PutObjectRequest to include the folder before the file name.

public bool UploadFileToS3(string uploadAsFileName, Stream ImageStream, S3CannedACL filePermission, S3StorageClass storageType, string toWhichBucketName)
{
    try
    {
        using(client = Amazon.AWSClientFactory.CreateAmazonS3Client(MY_AWS_ACCESS_KEY_ID, MY_AWS_SECRET_KEY))
        {
           PutObjectRequest request = new PutObjectRequest();
           request.WithKey( "folder" + "/" + uploadAsFileName );
           request.WithInputStream(ImageStream);
           request.WithBucketName(toWhichBucketName);
           request.CannedACL = filePermission;
           request.StorageClass = storageType;

           client.PutObject(request);
        }
    }
    catch
    {            
        return false;
    }
    return true;
}

This post that talks about uploading files to folder. They are using a TransferUtilityUploadRequest though, but it should work with the PutObjectRequest. Scroll to the bottom for the relevant example.

This post shows how to create a folder without uploading a file to it.

Hope this is helpful

Edit:
Updated the code to use a using block instead of calling Dispose per best practices.