Include arbitrary files in a PowerShell lambda

include_files_powershell_lambda.md

Include arbitrary files in a PowerShell lambda

Prerequisites

• powershell core
• aws cli
• Install-Module AWSLambdaPSCore -Scope CurrentUser
• Install-Module -Name AWS.Tools.Installer -Scope CurrentUser (only if using AWS modules)
• Install-AWSToolsModule -Name Common (only if using AWS modules)
• lambda execution role

Start a lamda powershell project.

New-AWSPowerShellLambda -ScriptName MyFirstPSScript -Template Basic
cd MyFirstPSScript

Create a custom powershell module to hold all your stuff.

mkdir -p StuffModule/Stuff
New-Item StuffModule/Stuff.psm1

Add a function to StuffModule/Stuff.psm1 to return the stuff path.

function Get-StuffPath {
  Join-Path -Path $PSScriptRoot -ChildPath 'Stuff'
}

Move whatever files you want included in the lambda to the StuffModule/Stuff folder.

Create a module manifest

New-ModuleManifest ./StuffModule/Stuff.psd1 -RootModule Stuff.psm1 -Description 'StuffModule'

Import the module, verify you can see your stuff.

Import-Module ./StuffModule/Stuff.psd1
Get-Module Stuff
Get-StuffPath
dir (Get-StuffPath)

Add a required statement for the new stuff module to MyFirstPSScript\MyFirstPSScript.ps1.

# PowerShell script file to be executed as a AWS Lambda function.
#
# When executing in Lambda the following variables will be predefined.
#   $LambdaInput - A PSObject that contains the Lambda function input data.
#   $LambdaContext - An Amazon.Lambda.Core.ILambdaContext object that contains information about the currently running Lambda environment.
#
# The last item in the PowerShell pipeline will be returned as the result of the Lambda function.
#
# To include PowerShell modules with your Lambda function, like the AWS.Tools.S3 module, add a "#Requires" statement
# indicating the module and version. If using an AWS.Tools.* module the AWS.Tools.Common module is also required.

#Requires -Modules @{ModuleName='AWS.Tools.Common';ModuleVersion='4.0.5.0'}
#Requires -Modules @{ModuleName='Stuff';ModuleVersion='0.0.1'}

# Uncomment to send the input event to CloudWatch Logs
# Write-Host (ConvertTo-Json -InputObject $LambdaInput -Compress -Depth 5)

Add a line to the end of MyFirstPSScript\MyFirstPSScript.ps1 to test that you can see all your stuff from the lambda's perspective. I don't know why, but running aws lambda invoke only seems to return the last line of the script's output so I will wrap everything in one line of json using ConvertTo-Json -Compress.

(dir (Get-StuffPath)).FullName | ConvertTo-Json -Compress

Publish and test the lambda function.

Publish-AWSPowerShellLambda -ScriptPath .\MyFirstPSScript.ps1 -Name  MyFirstPSScript -Region us-east-1

aws lambda invoke --function-name MyFirstPSScript out.txt

You should see a list of the fullpath to all the stuff you included in the StuffModule/Stuff directory.

Notes

It's important to import the module from your relative path before you publish the lambda. Otherwise you will get an error.

Saving module Stuff
Save-Package: C:\program files\powershell\7\Modules\PowerShellGet\PSModule.psm1:11794
 Line |
11794 |              $null = PackageManagement\Save-Package @PSBoundParameters
      |                      ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      | No match was found for the specified search criteria and module name 'Stuff'. Try Get-PSRepository to see all
      | available registered module repositories.