Nuget dependency is throwing System.IO.FileNotFoundException

[rianjs]

I'm not sure if this is a libphonenumber issue, or an AWS Lambda test tool issue. It has the feel of an issue with the test tool.

Repro steps:

1. Install the AWS Lambda test tool package: https://aws.amazon.com/blogs/developer/debugging-net-core-aws-lambda-functions-using-the-aws-net-mock-lambda-test-tool/
2. Create an empty Serverless Lambda app
3. Add the libphonenumber package as a dependency
4. In the Function constructor, do var foo = PhoneNumberUtil.GetInstance();
5. Run the debugger
6. Send any request

The constructor doesn't run at all.

System.IO.FileNotFoundException: Could not load file or assembly 'PhoneNumbers, Version=8.10.6.0, Culture=neutral, PublicKeyToken=null'. The system cannot find the file specified.
   at Mercury.Function..ctor()

The smallest repro case I could come up with attached here.
AWSServerlessApp.zip

[rianjs]

I have also downloaded the source code for libphonenumber, and added that csproj as a project reference in a lambda solution. It builds fine, but as soon as I invoke the lambda via the test tool, the same error occurs.

I have opened a bug in the libphonenumber project as well, as I'm not sure which side the problem is on:
twcclegg/libphonenumber-csharp#95

[klaytaybai]

Hi @rianjs, we're looking into this. I've confirmed that it doesn't work in the test tool, but the same library will work in a console app--as you state in the issue for the other repo. I've also verified that some other libraries work with the test tool, so now I'll continue investigating why this one doesn't. Let me know if you have updates on your end. Thanks for reporting it.

[rianjs]

If the code was open, I would have been happy to work through it myself. ;P

I'm guessing it works fine in a "real" lambda environment.

[mikylebaksh]

The Problem:

I have a similar issue, but with a different library. I have a netcore2.1 lambda project that references Microsoft.EntityFrameworkCore 2.2.3 and Microsoft.EntityFrameworkCore.Sqlite 2.2.3. When running in visual studio with the Mock Lambda Test Tool, the following exception is thrown:

System.IO.FileNotFoundException: Could not load file or assembly 'Microsoft.Data.Sqlite, Version=2.2.3.0, Culture=neutral, PublicKeyToken=adb9793829ddae60'. The system cannot find the file specified.
   at AWSLambda_EfCoreTest.Function.FunctionHandler(String input, ILambdaContext context)

I have confirmed that this lambda function can be deployed and run successfully in the real AWS cloud based Lambda environment.

See the small reproduction project attached

The Source:

I cloned the aws-lambda-dotnet repo and ran the test tool. I created new unit test to invoke the tool and step into the code. The test tool throws the exception during the Amazon.Lambda.TestTool.Runtime::LambdaAssemblyResolver::OnResolving method. This method cannot resolve AssemblyName = Microsoft.Data.Sqlite and will return null. This method is the last method called before the LoadContext has to call a System.IO.FileNotFoundException if the assembly is not resolved.

---

The solution posted in another issue works. In that issue, the author simply downgraded to a 2.1.* version. If we downgrade to 2.1.8 for both ef core references, the test tool starts working again. However this is not an option for me. I'm trying to take advantage of new features in ef core 2.2.*. IMO the tool should be able to load assemblies that are also supported in lambda.

This open issue in the corefx repo may give hints into the underlying issue.

I would explore further, but I don't have the time. Any ideas?

AWSLambda_NetCore21-EfCore22Test.zip

[normj]

I pushed out version 0.9.2 that has a change to how dependencies are searched for. With this change I was able to execute a lambda function with this tool that used libphonenumber.

If you are using Visual Studio and the AWS Toolkit for Visual Studio the update to 0.9.2 should happen automatically the next time you open your solution assuming you are online.

[normj]

Also @rianjs, the code for the mock test tool is open source and can be found in this repo at https://github.com/aws/aws-lambda-dotnet/tree/master/Tools/LambdaTestTool

[mikylebaksh]

Hey @normj,

Thanks for the help so far. I updated the tool to 0.9.2. I'm still getting System.IO.FileNotFoundException. Are you able to replicate using my sample project listed above?

For now, I can work around by kicking off my lambda functions for local development via a console app.

[rianjs]

Hmm, this still doesn't work for me.

[rianjs]

My previous comment, which I've edited, was wrong. Latest problem was just PEBKAC. The LibPhoneNumber assembly was found just fine.

[mrcunninghamz]

I am experiencing this issue in 0.9.2 with a nuget package that is being referenced from another project that my lambda project is dependent on.

[jiabiao]

I am experiencing the same issue in 0.9.2.
The test tool already loaded the Microsoft.Extensions.* 2.1., so It will fail if we want to use Microsoft.Extensions. 2.2.*.

Can you resolve this issue?

[AngelVenchev]

@jiabiao I am having the same issue.

System.IO.FileLoadException: Could not load file or assembly 'Microsoft.Extensions.DependencyInjection.Abstractions, Version=2.2.0.0, Culture=neutral, PublicKeyToken=adb9793829ddae60'. Could not find or load a specific file. (Exception from HRESULT: 0x80131621)

Version 0.9.2

[IdresAhmed]

@AngelVenchev Could you try changing version from 2.2 to 2.1? This worked for me for a similar issue. May have to do with Lambda not supporting .Net Core 2.2