'ILambdaContext.InvokedFunctionArn' always returning 'null'

Description

I’ve created a new lambda function and I wanted to get the ARN for the function to pass along into my code for further processing. However, ILambdaContext.InvokedFunctionArn is always returning null, both when testing locally, as well as when calling the function in the real environment.

The documentation for the property does not state it can ever be null:

The ARN used to invoke this function. It can be function ARN or alias ARN. An unqualified ARN executes the $LATEST version and aliases execute the function version they are pointing to.

Reproduction Steps

1. Create empty lambda
2. Access the InvokedFunctionArn property in the ILambdaContext passed into the function
3. Check that the value is always null

Environment

• Package Version: Amazon.Lambda.Core v1.2.0
• OS Info: Windows 10
• Build Environment Visual Studio 2019
• Targeted .NET Platform: NetCore 3.1

Resolution

• 👋 I can/would-like-to implement a fix for this problem myself

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This is a 🐛 bug-report

[ashishdhingra]

The feature to set the default values on the ILambdaContext for FunctionName, InvokedFunctionArn and AwsRequestId has been released in version 0.14.0 of Amazon.Lambda.TestTool.

[normj]

Agreed we should not close this. It goes along with other feature requests to customize the context object. Plus I do think a dummy arn is better then a null arn.