How to build, package, and publish .NET C# Lambda functions with the AWS CDK?

My question is based on this article. I found an issue when I have a .NET project referencing another project.

I added the Bundling Options like this.

            var buildOption = new BundlingOptions()
            {
                Image = Runtime.DOTNET_6.BundlingImage,
                User = "root",
                OutputType = BundlingOutput.ARCHIVED,
                Command = new string[] {
                   "/bin/sh",
                    "-c",
                    " dotnet tool install -g Amazon.Lambda.Tools"+
                    " && dotnet build"+
                    " && dotnet lambda package --output-package /asset-output/function.zip"
                    }
            };

My goal:

• Automatically build the lambda code and zip the code when running: cdk deploy.

After I followed the article, I got these errors.

Bundling asset BervProjectMergePDFInfraStack/PdfMerger/Code/Stage...
You can invoke the tool using the following command: dotnet-lambda
Tool 'amazon.lambda.tools' (version '5.6.4') was successfully installed.
MSBuild version 17.3.2+561848881 for .NET
  Determining projects to restore...
  Skipping project "/BervProject.MergePDF.S3/BervProject.MergePDF.S3.csproj" because it was not found.
  Skipping project "/BervProject.MergePDF.S3/BervProject.MergePDF.S3.csproj" because it was not found.
  Restored /asset-input/BervProject.MergePDF.Lambda.csproj (in 9.22 sec).
/var/lang/bin/sdk/6.0.407/Microsoft.Common.CurrentVersion.targets(2066,5): warning : The referenced project '../../../BervProject.MergePDF.S3/BervProject.MergePDF.S3.csproj' does not exist. [/asset-input/BervProject.MergePDF.Lambda.csproj]
/asset-input/Startup.cs(2,28): error CS0234: The type or namespace name 'S3' does not exist in the namespace 'BervProject.MergePDF' (are you missing an assembly reference?) [/asset-input/BervProject.MergePDF.Lambda.csproj]
/asset-input/Startup.cs(3,28): error CS0234: The type or namespace name 'S3' does not exist in the namespace 'BervProject.MergePDF' (are you missing an assembly reference?) [/asset-input/BervProject.MergePDF.Lambda.csproj]
/asset-input/Functions.cs(13,26): error CS0246: The type or namespace name 'IMerger' could not be found (are you missing a using directive or an assembly reference?) [/asset-input/BervProject.MergePDF.Lambda.csproj]
/asset-input/Functions.cs(17,26): error CS0246: The type or namespace name 'IMerger' could not be found (are you missing a using directive or an assembly reference?) [/asset-input/BervProject.MergePDF.Lambda.csproj]

Build FAILED.

/var/lang/bin/sdk/6.0.407/Microsoft.Common.CurrentVersion.targets(2066,5): warning : The referenced project '../../../BervProject.MergePDF.S3/BervProject.MergePDF.S3.csproj' does not exist. [/asset-input/BervProject.MergePDF.Lambda.csproj]
/asset-input/Startup.cs(2,28): error CS0234: The type or namespace name 'S3' does not exist in the namespace 'BervProject.MergePDF' (are you missing an assembly reference?) [/asset-input/BervProject.MergePDF.Lambda.csproj]
/asset-input/Startup.cs(3,28): error CS0234: The type or namespace name 'S3' does not exist in the namespace 'BervProject.MergePDF' (are you missing an assembly reference?) [/asset-input/BervProject.MergePDF.Lambda.csproj]
/asset-input/Functions.cs(13,26): error CS0246: The type or namespace name 'IMerger' could not be found (are you missing a using directive or an assembly reference?) [/asset-input/BervProject.MergePDF.Lambda.csproj]
/asset-input/Functions.cs(17,26): error CS0246: The type or namespace name 'IMerger' could not be found (are you missing a using directive or an assembly reference?) [/asset-input/BervProject.MergePDF.Lambda.csproj]
    1 Warning(s)
    4 Error(s)

Time Elapsed 00:00:14.36
Unhandled exception. System.Exception: Failed to bundle asset BervProjectMergePDFInfraStack/PdfMerger/Code/Stage, bundle output is located at D:\Projects\Github\MergePDFOnline\cdk.out\asset.8002390a958718ff5743fdca447ec443297b0f1ed8dc390b1c49e2e8cbb60427-error: Error: docker exited with status 1
   at Amazon.JSII.Runtime.Services.Client.TryDeserialize[TResponse](String responseJson)
   at Amazon.JSII.Runtime.Services.Client.ReceiveResponse[TResponse]()
   at Amazon.JSII.Runtime.Services.Client.Send[TRequest,TResponse](TRequest requestObject)
   at Amazon.JSII.Runtime.Services.Client.Create(CreateRequest request)
   at Amazon.JSII.Runtime.Services.Client.Create(String fullyQualifiedName, Object[] arguments, Override[] overrides, String[] interfaces)
   at Amazon.JSII.Runtime.Deputy.DeputyBase..ctor(DeputyProps props)
   at Constructs.Construct..ctor(DeputyProps props)
   at Amazon.CDK.Resource..ctor(DeputyProps props)
   at Amazon.CDK.AWS.Lambda.FunctionBase..ctor(DeputyProps props)
   at Amazon.CDK.AWS.Lambda.Function..ctor(Construct scope, String id, IFunctionProps props)
   at BervProject.MergePDF.Infra.BervProjectMergePDFInfraStack..ctor(Construct scope, String id, IStackProps props) in D:\Projects\Github\MergePDFOnline\BervProject.MergePDF.Infra\BervProjectMergePDFInfraStack.cs:line 32
   at BervProject.MergePDF.Infra.Program.Main(String[] args) in D:\Projects\Github\MergePDFOnline\BervProject.MergePDF.Infra\Program.cs:line 13

I think the build process is not running in the lambda project directory, so the process failed.

Do you have another solution or alternative at least I can ensure the lambda will be deployed correctly. My current condition is the Lambda doesn't have any assemblies yet.

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If you need more details about my code is here.