Powershell: Load and use a Dynamic Module directly from GitHub in Tasks

[#1]

I use a library of Powershell functions frequently in my Morpheus Tasks. I decided to build these into a script and store it on Github. For convenience I developed a Powershell function which you can add to your Morpheus Powershell tasks. The function takes a raw Url from Github and loads the Powershell into a Dynamic Module which then gives the Morpheus Task access to the library of Powershell functions.

Follow the example below to try this for yourself.

Create a Powershell Task type, set the Execute Target as Resource. and add this function into the Task script

# Declare the function - this will be standard in all Tasks
Function New-ModulefromGitHub {
    <#
    .SYNOPSIS
    Takes a Github Raw url, downloads the Powershell Script and Executes as a Dynamic Module

    .DESCRIPTION
    Takes a Github Raw url, downloads the Powershell Script and Executes as a Dynamic Module

    Examples:
    New-ModulefromGitHub -ScriptUrl <Github Raw URL for the Powershell script> -Name "GibModule"

    .PARAMETER ScriptUrl
    GitHub Raw Url to Powershell script

    .PARAMETER Name
    A String to identify the Dynamic Module name

    .OUTPUTS
    Loads a Dynamic Module

    #>     
    [CmdletBinding()]
    Param (
        [Parameter(Mandatory=$true,Position=0)]
        [String]$ScriptUrl,
        [Parameter(Mandatory=$true,Position=1)]
        [String]$Name
    )
    if ($ScriptUrl) {
        try {
            $Response = Invoke-WebRequest -Uri $ScriptUrl -UseBasicParsing -ErrorAction SilentlyContinue
            $StatusCode = $Response.StatusCode
        }
        catch {
            $StatusCode = $_.Exception.Response.StatusCode
            Write-Warning "Cannot locate Script Url $ScriptUrl - Status:$StatusCode"
        }
        if ($StatusCode -eq 200) {
            try {
                New-Module -Name $Name -ScriptBlock ([ScriptBlock]::Create($Response.Content))
            }
            catch {
                Write-Error "ScriptUrl is not a valid Powershell Module ScriptBlock"
            }           
        }
    } else {
        Write-Warning "You must enter a Script URL"
    }
}

# Start your custom script here

# Git Raw URL of a scipt to load as a Module. (Note it must be a raw Url type)
$GitUrl = "https://raw.githubusercontent.com/spottsmorpheus/invokePSTask/main/Examples/moduleExample.ps1"

# Hide Progress updates in Morpheus
$ProgressPreference="SilentlyContinue"

# Load the Dynamic Module using the function created above. To prevent output being written into the
# script assign the command below into a variable eg $NoOutput = New-ModuleFromGitHub ...

New-ModuleFromGitHub -ScriptUrl $GitUrl -Name "Git-Test"

#Fuctions are now available - use them as you normally would. You may access Morpheus Variables
$Inst = "<%=instance.name%>"
#Call a Function defined in the Module - here you can pass in any Morpheus Variables
$Status = Get-InstanceInfo -Instance $Inst 
$Status | ConvertTo-Json -Depth 3

#End of Task

Execute the task against an Instance type. It should generate output as so

Steve Potts
Morpheus Support EMEA

[cbunge]

Ooo this is nifty

[cdtaylor]

Brill work. Thanks for sharing

[#4]

Nice work Steve, keep them coming!