AWS .NET SDK DynamoDB LoadAsync返回“无法加载类型”错误

Question

I'm developing an application using AWS Lambda and DynamoDB. I'm getting the error below when I try to test my lambda function.

Error:

{ "errorType": "AggregateException", "errorMessage": "One or more errors occurred. (Could not load type 'Amazon.Runtime.Internal.AsyncRunner' from assembly 'AWSSDK.Core, Version=3.3.0.0, Culture=neutral, PublicKeyToken=885c28607f98e604'.)", "stackTrace": [ "at System.Threading.Tasks.Task.ThrowIfExceptional(Boolean includeTaskCanceledExceptions)", "at System.Threading.Tasks.Task.Wait(Int32 millisecondsTimeout, CancellationToken cancellationToken)", "at ProChiller.SyncDevices.QueryDevices(Devices input)", "at lambda_method(Closure , Stream , Stream , ContextInfo )" ], "cause": { "errorType": "TypeLoadException", "errorMessage": "Could not load type 'Amazon.Runtime.Internal.AsyncRunner' from assembly 'AWSSDK.Core, Version=3.3.0.0, Culture=neutral, PublicKeyToken=885c28607f98e604'.", "stackTrace": [ "at Amazon.DynamoDBv2.DataModel.DynamoDBContext.LoadAsync[T](Object hashKey, CancellationToken cancellationToken)", "at ProChiller.SyncDevices.d__6.MoveNext()" ] } }

As you can see it seems to not be able to load 'AsyncRunner' from the AWSSDK.

Code:

private static AmazonDynamoDBClient amazonDynamoDBClient = new AmazonDynamoDBClient();

public static Devices GetDeviceHandler(Devices input, ILambdaContext context)
{
     var task = QueryDevices(input);
     task.Wait();
     return task.Result;   
}

static async Task<Devices> QueryDevices(Devices device)
{
    DynamoDBContext dbctx = new DynamoDBContext(amazonDynamoDBClient);
    var operation = dbctx.LoadAsync<Devices>(device.TccvID);
    Devices devices = await operation;
    return devices;
}

What I've Tried:

I tried a number of different ways of querying with Dynamo, but this method is the cleanest and normally gets me the results I'm looking for.

Now I swear I had this code or very similar code working before at one point and I have in the past had issues with the SDK version causing problems when it was updated. I tried rolling back the version of the AWSSDK.Core to see if it was a problem with the newer version of it and my code. However, no matter what version I rollback to I still get the same error.

I've googled around in hopes that someone had a similar issue with that type load , but I could find anyone having written about this specific error or one similar enough that I could extrapolate. I was hoping maybe there was documentation of a specific SDK version I should be running for this type, but was not able to find anything.

The code I've posted is actually a paired down version where I tried to make it as simple as possible in hopes that there was something else I was doing that was causing this error.

Other Build Info:

The application is .Net Core 1.0.

AWSSDK.Core version is 3.3.24.3, but I do notice that in the error is says 'version=3.3.0.0'.

The Question:

Does anyone have an idea what might be causing this type load error? Is there a specific version of the SDK I should roll back to in order to fix this or am I barking up the wrong tree?

Thanks in advance for any help!

Answer 1

Short answer is I think you need to update to a newer version of AWSSDK.DynamoDBv2.

We had a pull request that removed the need for AsyncRunner from AWSSDK.Core that AWSSDK.DynamoDBv2 needed and so it was removed. In hindsight seeing your problem it wasn't the right decision to remove. If you update both your AWSSDK.Core and AWSSDK.DynamoDBv2 packages you would have been fine but in this case you updated just AWSSDK.Core but your older version of AWSSDK.DynamoDBv2 is still referencing AsyncRunner from AWSSDK.Core.

I'll have a discussion with the team and see about adding back AsyncRunner for cases like this.