Trying to make if/else powershell for ARM template

Question

I have a PowerShell script for an ARM template to deploy some resources into Azure, more specifically ASE v2.

My ARM template has a condition in it stating:

"sv-ase-version": "v2",

    "sv-asp-template-filenameHash": {
      "v1": "[concat(variables('sv-baseURI'),concat('/azuredeploy-asp.v1.json',parameters('_artifactsLocationSasToken')))]",
      "v2": "[concat(variables('sv-baseURI'),concat('/azuredeploy-asp.json',parameters('_artifactsLocationSasToken')))]"
    },

What i have right now in PowerShell:

Param(

    [string] $TemplateFile = 'azuredeploy-dev.json',
    [string] $TemplateParametersFile = 'azuredeploy-dev.parameters.json',

)

$TemplateFile = [System.IO.Path]::GetFullPath([System.IO.Path]::Combine($PSScriptRoot, $TemplateFile))
$TemplateParametersFile = [System.IO.Path]::GetFullPath([System.IO.Path]::Combine($PSScriptRoot, $TemplateParametersFile))

What i wanna add in PowerShell is:

Param(

    [string] $TemplateFile = 'azuredeploy-dev.json',
    [string] $TemplateParametersFile = 'azuredeploy-dev.parameters.json',
    [string] $TemplateFilev2 = 'azuredeploy.json',
    [string] $TemplateParametersFilev2 = 'azuredeploy.parameters.json',

)

#Checking if this is the correct way to do it

if ("sv-ase-version" -eq "v1") {

    $TemplateFile = [System.IO.Path]::GetFullPath([System.IO.Path]::Combine($PSScriptRoot, $TemplateFile))
    $TemplateParametersFile = [System.IO.Path]::GetFullPath([System.IO.Path]::Combine($PSScriptRoot, $TemplateParametersFile))

}
else {

    $TemplateFilev2 = [System.IO.Path]::GetFullPath([System.IO.Path]::Combine($PSScriptRoot, $TemplateFilev2))
    $TemplateParametersFilev2 = [System.IO.Path]::GetFullPath([System.IO.Path]::Combine($PSScriptRoot, $TemplateParametersFilev2))

}

My intention: make the switch in the JSON file, without needing to change things in PowerShell.

Would this work? How would you approach this differently?

Thanks.

Answer 1

The easiest way to do that is use a parameter in the template, call it something like deploymentPrefix :

"deploymentPrefix": {
    "type": "string",
    "defaultValue": "dev",
    "allowedValues": [
        "dev",
        "prod"
    ],
    "metadata": {
        "description": "Resources created will be prefixed with this."
    }
},

and based on the value of that parameter decide what to deploy in the template:

"variables": {
    "template-dev": "someurl",
    "template-prod": "someotherurl",
    "template-url": "[concat('template-', parameters('deploymentPrefix))]"
    ...
}

and in your powershell you would just use New-AzureRmResourceGroupDeployment and pass that (dev or prod) to the parameter and the template would figure out what to use for the template-url variable.