AWS S3 Get object not working. Getting corrupt file

Question

I have a .zip file on an S3 bucket. When I try to get it and save it as a file it is corrupt and can't be opened. I don't know what to do, is really hard to get that S3 zip file. I am using this code as a guide https://docs.aws.amazon.com/AmazonS3/latest/userguide/download-objects.html. I'm currently on Unity, but the SDK for .NET should work. The resulted file has the first 7.4 kb all NULL. This is the code that gets the zip file, returns the buffer, and saves it with File.WriteAllBytes: ``` ///

/// Get Object from S3 Bucket ///

public async Task GetZip(string pFile) { try { Debug.Log("KEY: " + pFile); GetObjectRequest request = new GetObjectRequest { BucketName = S3Bucket, Key = pFile }; using (GetObjectResponse response = await S3Client.GetObjectAsync(request)) using (Stream responseStream = response.ResponseStream) { Debug.Log("Response stream"); if (responseStream != null) { byte[] buffer = new byte[(int)response.ResponseStream.Length]; int result = await responseStream.ReadAsync(buffer, 0, (int)response.ResponseStream.Length); Debug.Log("Stream result: " + result); File.WriteAllBytes(songPath, buffer); Debug.Log("Readed all bytes: " + buffer.Length + " - " + ((int)response.ResponseStream.Length)); return buffer; } else { Debug.Log("Response is null"); } } } catch (AmazonS3Exception e) { // If bucket or object does not exist Debug.Log("Error encountered ***. Message:"+ e.Message + " when reading object"); } catch (Exception e) { Debug.Log("Unknown encountered on server. Message:"+ e.Message + " when reading object"); } return null; } ```

Answer

C# Directly supports writing the stream to a file:

```cs
using (var response = await S3Client.GetObjectAsync(request))
using (var responseStream = response.ResponseStream)
using (var outputFileStream = new FileStream(songPath, FileMode.Create))
{
    await responseStream.CopyToAsync(outputFileStream);
}
```

Answer

Is the file truly corrupt or has it been unzipped and you didn't expect it to be?  From memory the Content Encoding metadata on the object in S3 will influence whether a zip file is transparently unzipped on the fly.

Answer

Ok. Fiddled with your code a bit. And got `NoSupported` errors on responseStream.Length.

I changed to code to using `response.ContentLength` and it started working for me.

This is the code I ended up with:

```cs
async Task GetZip(string pFile)
{
    try
    {
        Console.WriteLine("KEY: " + pFile);
        Amazon.S3.Model.GetObjectRequest request = new Amazon.S3.Model.GetObjectRequest
        {
            BucketName = S3Bucket,
            Key = pFile
        };
        using (Amazon.S3.Model.GetObjectResponse response = await S3Client.GetObjectAsync(request))
        using (Stream responseStream = response.ResponseStream)
        {
            Console.WriteLine("Response stream");
            if (responseStream != null)
            {
                byte[] buffer = new byte[(int)response.ContentLength];
                int result = await responseStream.ReadAsync(buffer, 0, (int)response.ContentLength);
                Console.WriteLine("Stream result: " + result);
                File.WriteAllBytes(songPath, buffer);
                Console.WriteLine("Readed all bytes: " + buffer.Length + " - " + ((int)response.ContentLength));
                return buffer;
            }
            else
            {
                Console.WriteLine("Response is null");
            }
        }
    }
    catch (Amazon.S3.AmazonS3Exception e)
    {
        // If bucket or object does not exist
        Console.WriteLine("Error encountered ***. Message:"+ e.Message + " when reading object");
    }
    catch (Exception e)
    {
        Console.WriteLine("Unknown encountered on server. Message:"+ e.Message + " when reading object");
    }
    return new byte[0];
}

GetZip(pFile).Wait();
```

AWS S3 Get object not working. Getting corrupt file

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