techthoughts2/PowerShell-Lambda-Template

Plaster template to bootstrap a PowerShell Lambda with the AWS Serverless Application Model.

PowerShell-Lambda-Template

Synopsis

This template can provide a PowerShell developer with a faster feedback loop when developing a PowerShell Lambda function.

Description

Quickly iterate development of PowerShell Lambda functions using this template workflow.

This workflow uses AWS Serverless Application Module (SAM) template to describe the Lambda function as an application. The template can then be transformed, deployed, updated, and torn down quickly via command line, enabling the developer to observe and receive feedback quickly.

File Content

• Deploy.ps1: The Deploy.ps1 script will deploy the PowerShell Lambda application using the AWS SAM model.
• serverless.template: The serverless.template is the SAM (CloudFormation) template that describes the AWS Lambda.
• PowerShellLambda.ps1: The PowerShellLambda.ps1, which will be renamed by Plaster as the Lambda name, is the PowerShell Lambda code.
• plasterManifest.xml: The plasterManifest.xml contains the Plaster construct that transforms the template into actual project folder structures.

Prerequisites

• .Net Core SDK
• AWS CLI
• PowerShell Core 6
• PowerShell modules:
  • Plaster- Plaster is a template-based file and project generator similar to Yeoman
  • AWSPowerShell.NetCore
  • AWSLambdaPSCore

Assumptions

Assuming you already have:

• Pre-created S3 bucket in the target AWS account.
• Already configured the AWSPowerShell.NetCore and AWS CLI credentials/ profiles/ default regions.
  • AWS PowerShell - Using AWS Credentials
  • AWS CLI - Configuring the AWS CLI

Usage

Once you have the prerequisites ready, use the following steps to create a new PowerShell SAM Lambda project using the template.

NOTE: make sure you have the AWS credential configured for both AWS PowerShell and AWS CLI.

High Level Steps

1. Open the PowerShell Core 6 console.

2. Type the following command and press enter:

   Invoke-Plaster -TemplatePath 'C:\Code\PowerShell-Lambda-Template' -DestinationPath C:\Code\MyHelloWorldLambda

3. You will be prompted for a Lambda name, S3 bucket name. Please provide answers.

   (Hint: Press Ctrl-C to stop)

4. You should see output similar to the following:

   

5. Navigate to the C:\Code folder. It will contain the following folder and file structure. The descriptions are in the brackets.

   C:\Code
   \---MyHelloWorldLambda (from the -Destination of Invoke-Plaster)
       \---HelloWorld (The lambda name)
               Deploy.ps1 (The PowerShell Script for code deployemnt)
               HelloWorld-serverless.template (SAM template)
               HelloWorld.ps1 (The actual PowerShell Lambda code)
   

6. Open the HelloWorld folder in Visual Studio Code.

7. The HelloWorld.ps1 contains the basic PowerShell Code to output environmental variables.

8. Open the Deploy.ps1 file

9. Make sure you have PowerShell 6.x selected on the bottom right. This ensures we are using PowerShell Core 6 in the VSCode's Integrated Console.

10. Press Ctrl + F5 to deploy the default Lambda to the AWS account (using default region).

    NOTE: make sure you have the AWS credential configured for both AWS PowerShell and AWS CLI.

11. Now, you can iterate quickly with:

    1. update the HelloWorld.ps1 with the code you want.
    2. Go to Deploy.ps1
    3. Press Ctrl + F5 to update the Lambda, test, observe and repeat.

Notes

If in VSCode, run the Deploy.ps1 file using Ctrl+F5. F8 or select and run won't work.