Add generate_only parameter to skip terraform init/plan/apply

Co-authored-by: jaredfholgate <1612200+jaredfholgate@users.noreply.github.com>

Author: Copilot

src/ALZ/Private/Deploy-Accelerator-Helpers/Invoke-Terraform.ps1

@@ -19,11 +19,20 @@ function Invoke-Terraform {
         [Parameter(Mandatory = $false)]
         [string] $outputFilePath = "",
 
-        [Parameter(Mandatory = $false)]
-        [switch] $silent
+        [Parameter(Mandatory = $false)]
+        [switch] $silent,
+
+        [Parameter(Mandatory = $false)]
+        [switch] $generateOnly
     )
 
-    if ($PSCmdlet.ShouldProcess("Apply Terraform", "modify")) {
+    if ($PSCmdlet.ShouldProcess("Apply Terraform", "modify")) {
+        
+        if ($generateOnly) {
+            Write-InformationColored "Generate only mode enabled. Terraform files have been generated but terraform init, plan, and apply have been skipped." -ForegroundColor Green -NewLineBefore -InformationAction Continue
+            return
+        }
+
         # Check and Set Subscription ID
         $removeSubscriptionId = $false
         if ($null -eq $env:ARM_SUBSCRIPTION_ID -or $env:ARM_SUBSCRIPTION_ID -eq "") {

src/ALZ/Private/Deploy-Accelerator-Helpers/New-Bootstrap.ps1

@@ -56,9 +56,13 @@ function New-Bootstrap {
         [string[]]
         $inputConfigFilePaths = @(),
 
-        [Parameter(Mandatory = $false)]
-        [string[]]
-        $starterAdditionalFiles = @()
+        [Parameter(Mandatory = $false)]
+        [string[]]
+        $starterAdditionalFiles = @(),
+
+        [Parameter(Mandatory = $false)]
+        [switch]
+        $generateOnly
     )
 
     if ($PSCmdlet.ShouldProcess("ALZ-Terraform module configuration", "modify")) {
@@ -269,16 +273,26 @@ function New-Bootstrap {
             Remove-UnrequiredFileSet -path $starterModulePath -foldersOrFilesToRetain $foldersOrFilesToRetain -subFoldersOrFilesToRemove $subFoldersOrFilesToRemove -writeVerboseLogs:$writeVerboseLogs.IsPresent
         }
 
-        # Running terraform init and apply
-        Write-InformationColored "Thank you for providing those inputs, we are now initializing and applying Terraform to bootstrap your environment..." -ForegroundColor Green -NewLineBefore -InformationAction Continue
-
-        if($autoApprove) {
-            Invoke-Terraform -moduleFolderPath $bootstrapModulePath -autoApprove -destroy:$destroy.IsPresent
-        } else {
-            Write-InformationColored "Once the plan is complete you will be prompted to confirm the apply." -ForegroundColor Green -NewLineBefore -InformationAction Continue
-            Invoke-Terraform -moduleFolderPath $bootstrapModulePath -destroy:$destroy.IsPresent
+        # Running terraform init and apply
+        if ($generateOnly) {
+            Write-InformationColored "Thank you for providing those inputs, we are now generating the Terraform files for your environment..." -ForegroundColor Green -NewLineBefore -InformationAction Continue
+        } else {
+            Write-InformationColored "Thank you for providing those inputs, we are now initializing and applying Terraform to bootstrap your environment..." -ForegroundColor Green -NewLineBefore -InformationAction Continue
+        }
+
+        if($autoApprove) {
+            Invoke-Terraform -moduleFolderPath $bootstrapModulePath -autoApprove -destroy:$destroy.IsPresent -generateOnly:$generateOnly.IsPresent
+        } else {
+            if (!$generateOnly) {
+                Write-InformationColored "Once the plan is complete you will be prompted to confirm the apply." -ForegroundColor Green -NewLineBefore -InformationAction Continue
+            }
+            Invoke-Terraform -moduleFolderPath $bootstrapModulePath -destroy:$destroy.IsPresent -generateOnly:$generateOnly.IsPresent
+        }
+
+        if ($generateOnly) {
+            Write-InformationColored "Terraform files have been generated successfully! You can now use them with your custom pipeline or terraform state configuration." -ForegroundColor Green -NewLineBefore -InformationAction Continue
+        } else {
+            Write-InformationColored "Bootstrap has completed successfully! Thanks for using our tool. Head over to Phase 3 in the documentation to continue..." -ForegroundColor Green -NewLineBefore -InformationAction Continue
         }
-
-        Write-InformationColored "Bootstrap has completed successfully! Thanks for using our tool. Head over to Phase 3 in the documentation to continue..." -ForegroundColor Green -NewLineBefore -InformationAction Continue
     }
 }

src/ALZ/Public/Deploy-Accelerator.ps1

@@ -183,7 +183,15 @@ function Deploy-Accelerator {
             HelpMessage = "[OPTIONAL] Determines whether to skip the requirements check for the ALZ PowerShell Module version only. This is not recommended."
         )]
         [Alias("skipAlzModuleVersionRequirementsCheck")]
-        [switch] $skip_alz_module_version_requirements_check
+        [switch] $skip_alz_module_version_requirements_check,
+
+        [Parameter(
+            Mandatory = $false,
+            HelpMessage = "[OPTIONAL] Only generate Terraform files without running terraform init, plan, or apply. This is useful for custom tfstate configurations or other pipelines. Environment variable: ALZ_generate_only. Config file input: generate_only."
+        )]
+        [Alias("g")]
+        [Alias("generateOnly")]
+        [switch] $generate_only
     )
 
     $ProgressPreference = "SilentlyContinue"
@@ -380,7 +388,8 @@ function Deploy-Accelerator {
             -hclParserToolPath $hclParserToolPath `
             -convertTfvarsToJson:$inputConfig.convert_tfvars_to_json.Value `
             -inputConfigFilePaths $inputConfigFilePaths `
-            -starterAdditionalFiles $inputConfig.starter_additional_files.Value
+            -starterAdditionalFiles $inputConfig.starter_additional_files.Value `
+            -generateOnly:$inputConfig.generate_only.Value
     }
 
     $ProgressPreference = "Continue"

src/Tests/Unit/Public/Deploy-Accelerator.Tests.ps1

@@ -158,11 +158,18 @@ InModuleScope 'ALZ' {
                 Assert-MockCalled -CommandName New-ModuleSetup -Exactly 2
             }
 
-            It 'should call the correct functions for terraform module configuration' {
-                Deploy-Accelerator -i "terraform" -b "github" -inputs "example.yml"
-                Assert-MockCalled -CommandName Get-BootstrapAndStarterConfig -Exactly 1
-                Assert-MockCalled -CommandName New-Bootstrap -Exactly 1
-                Assert-MockCalled -CommandName New-ModuleSetup -Exactly 2
+            It 'should call the correct functions for terraform module configuration' {
+                Deploy-Accelerator -i "terraform" -b "github" -inputs "example.yml"
+                Assert-MockCalled -CommandName Get-BootstrapAndStarterConfig -Exactly 1
+                Assert-MockCalled -CommandName New-Bootstrap -Exactly 1
+                Assert-MockCalled -CommandName New-ModuleSetup -Exactly 2
+            }
+
+            It 'should call the correct functions for terraform module configuration with generate_only' {
+                Deploy-Accelerator -i "terraform" -b "github" -inputs "example.yml" -generate_only
+                Assert-MockCalled -CommandName Get-BootstrapAndStarterConfig -Exactly 1
+                Assert-MockCalled -CommandName New-Bootstrap -Exactly 1 -ParameterFilter { $generateOnly -eq $true }
+                Assert-MockCalled -CommandName New-ModuleSetup -Exactly 2
             }
         }
     }