demo-runtime-layer-function

Demo-runtime-layer-function

Initial demo application demo-runtime-layer-function uses AWS SAM to deploy the following:

1. PowerShell custom runtime based on provided.al2 as a Lambda layer.

2. Additional Lambda layer including the AWSTools for PowerShell with the following module.

   • AWS.Tools.Common

3. Both layers store their Amazon Resource Names (ARNs) as parameters in AWS Systems Manager Parameter Store which can be referenced in other templates

4. Lambda function with three different handler options.

To build the custom runtime and the AWS Tools for PowerShell layer for this example, AWS SAM uses a Makefile. This downloads the specified version of PowerShell and select modules from the AWSTools

Windows does not natively support Makefiles. When using Windows, you can use either Windows Subsystem for Linux (WSL), Docker Desktop or native PowerShell.

Pre-requisites:

• AWS Serverless Application Model (AWS SAM)
• If building on Windows:
  • Windows Subsystem for Linux (WSL) or
  • Docker Desktop or
  • PowerShell for Windows

Clone the repository and change into the example directory

git clone https://github.com/awslabs/aws-lambda-powershell-runtime
cd aws-lambda-powershell-runtime/examples/demo-runtime-layer-function

Use one of the "Build" options, A,B,C, depending on your operating system and tools.

A) Build using Linux or WSL

Build the custom runtime, Lambda layer, and function packages using native Linux or WSL.

sam build --parallel

B) Build using Docker

You can build the custom runtime, Lambda layer, and function packages using Docker. This uses a Linux-based Lambda-like Docker container to build the packages. Use this option for Windows without WSL or as an isolated Mac/Linux build environment.

sam build --parallel --use-container

C) Build using PowerShell for Windows

You can use native PowerShell for Windows to download and extract the custom runtime and Lambda layer files. This performs the same file copy functionality as the Makefile. It adds the files to the source folders rather than a build location for subsequent deployment with AWS SAM. Use this option for Windows without WSL or Docker.

.\build-layers.ps1

Test the function locally

Once the build process is complete, you can use AWS SAM to test the function locally.

sam local invoke

This uses a Lambda-like environment to run the function locally and returns the function response, which is the result of Get-AWSRegion.

Deploying to the AWS Cloud

Use AWS SAM to deploy the resources to your AWS account. Run a guided deployment to set the default parameters for the first deploy.

sam deploy -g

For subsequent deployments you can use sam deploy.

Enter a Stack Name and accept the remaining initial defaults.

AWS SAM deploys the infrastructure and outputs the details of the resources.

View, edit, and invoke the function in the AWS Management Console

You can view, edit code, and invoke the Lambda function in the Lambda Console.

Navigate to the Functions page and choose the function specified in the sam deploy Outputs.

Using the built-in code editor, you can view the function code.

This function imports the AWS.Tools.Common module during the init process. The function handler runs and returns the output of Get-AWSRegion.

To invoke the function, select the Test button and create a test event. For more information on invoking a function with a test event, see the documentation.

You can see the results in the Execution result pane.

You can also view a snippet of the generated Function Logs below the Response. View the full logs in Amazon CloudWatch Logs. You can navigate directly via the Monitor tab.

Invoke the function using the AWS CLI

From a command prompt, invoke the function. Amend the --function-name and --region values for your function. This should return "StatusCode": 200 for a successful invoke.

aws lambda invoke --function-name "aws-lambda-powershell-runtime-Function-6W3bn1znmW8G" --region us-east-1 invoke-result 

View the function results which are outputted to invoke-result.

cat invoke-result

Invoke the function using the AWS Tools for PowerShell

You can invoke the Lambda function using the AWS Tools for PowerShell and capture the response in a variable. The response is available in the Payload property of the $result object which can be read using the .NET StreamReader class.

$Response = Invoke-LMFunction -FunctionName aws-lambda-powershell-runtime-PowerShellFunction-HHdKLkXxnkUn -LogType Tail
[System.IO.StreamReader]::new($Response.Payload).ReadToEnd()

This outputs the result of AWS-GetRegion

Cleanup

To delete the AWS resources created, run the following and confirm that you want to delete the resources that were created by this template.

sam delete