I have a Lambda function written in C# that is unsuccessfully attempting to upload an object to an S3 bucket. For testing purposes, I am converting the input string to a byte array and using that as the object contents. My handler function is defined below:
public void FunctionHandler(string input, ILambdaContext context)
{
IAmazonS3 client = new AmazonS3Client(Amazon.RegionEndpoint.USEast1);
byte[] bytes = new byte[input.Length * sizeof(char)];
Buffer.BlockCopy(input.ToCharArray(), 0, bytes, 0, bytes.Length);
using (MemoryStream ms = new MemoryStream())
{
foreach (Byte b in bytes)
{
ms.WriteByte(b);
}
PutObjectRequest request = new PutObjectRequest()
{
BucketName = "BUCKET_NAME",
Key = "OBJECT_KEY",
InputStream = ms
};
client.PutObjectAsync(request);
}
}
The function runs without error, but the object is not written to S3. I feel that it might have something to do with the PutObjectAsync method, but I'm not positive. The IAmazonS3 interface includes a PutObject method, but when attempting to use that method I receive the following error:
'IAmazonS3' does not contain a definition for 'PutObject'
What is the best way to upload an object to an S3 bucket in a C# Lambda function?
This is the helper function I use to put S3 objects to S3, from a C# lambda function (and it works). You might be able to use this as a starting point for yours.
Not sure why you are converting your string to bytes, and in C#/Lambda you need to use the PutObjectAsync method, not the PutObject method:
public static async Task<bool> PutS3Object(string bucket, string key, string content)
{
try
{
using (var client = new AmazonS3Client(Amazon.RegionEndpoint.USEast1))
{
var request = new PutObjectRequest
{
BucketName = bucket,
Key = key,
ContentBody = content
};
var response = await client.PutObjectAsync(request);
}
return true;
}
catch (Exception ex)
{
Console.WriteLine("Exception in PutS3Object:" + ex.Message);
return false;
}
}
You should apply await with the Async
await client.PutObjectAsync(request);