Merge pull request #650 from Icinga:feature/adds_support_to_run_icinga_while_creating_no_new_instance

Feature: Adds support to not load a new PowerShell instance for command icinga

Adds support to run command `icinga` with new argument `-NoNewInstance`, to use `-RebuildCache` as example to update the current PowerShell instance with all applied changes, instead of create a new shell instance.

Does not support the argument `-DeveloperMode` in the same call, as Icinga for Window is dependent on these files for the current session.

Author: LordHepipud

doc/100-General/10-Changelog.md

@@ -25,6 +25,7 @@ Released closed milestones can be found on [GitHub](https://github.com/Icinga/ic
 ### Enhancements
 
 * [#544](https://github.com/Icinga/icinga-powershell-framework/issues/544) Adds support to configure the Icinga Director JSON string for registering hosts via self-service API
+* [#573](https://github.com/Icinga/icinga-powershell-framework/issues/573) Adds support to run command `icinga` with new argument `-NoNewInstance`, to use `-RebuildCache` as example to update the current PowerShell instance with all applied changes
 * [#619](https://github.com/Icinga/icinga-powershell-framework/pull/619) Adds feature to securely read enum provider values with new function `Get-IcingaProviderEnumData`
 * [#623](https://github.com/Icinga/icinga-powershell-framework/issues/623) Adds support to provide the Icinga service user written as `user@domain`
 * [#633](https://github.com/Icinga/icinga-powershell-framework/pull/633) Adds support for Icinga 2.14.0 native Icinga for Windows API communication

icinga-powershell-framework.psm1

@@ -84,6 +84,25 @@ function Import-IcingaForWindowsModulesInSession()
     }
 }
 
+function Import-IcingaForWindowsModules()
+{
+    [array]$IcingaForWindowsModules = Get-ChildItem -Path (Get-IcingaForWindowsRootPath);
+
+    foreach ($module in $IcingaForWindowsModules) {
+        if ($module.Name -Like 'icinga-powershell-*') {
+            try {
+                Import-Module $module.Name -Force -ErrorAction Stop;
+                Import-Module $module.Name -Force -Global -ErrorAction Stop;
+            } catch {
+                Write-Host ([string]::Format('Failed to import Icinga for Windows module "{0}": {1}', $module.Name, $_.Exception.Message));
+            }
+        }
+    }
+
+    Import-Module 'icinga-powershell-framework' -Force;
+    Import-Module 'icinga-powershell-framework' -Force -Global;
+}
+
 function Get-IcingaFrameworkCodeCacheFile()
 {
     return (Join-Path -Path (Get-IcingaCacheDir) -ChildPath 'framework_cache.psm1');
@@ -249,9 +268,15 @@ function Invoke-IcingaCommand()
         [switch]$NoSSLValidation = $FALSE,
         [switch]$RebuildCache    = $FALSE,
         [switch]$DeveloperMode   = $FALSE,
+        [switch]$NoNewInstance   = $FALSE,
         [array]$ArgumentList     = @()
     );
 
+    If ($DeveloperMode -And $NoNewInstance) {
+        Write-Host 'DeveloperMode is not supported while using NoNewInstance argument.' -ForegroundColor red;
+        return;
+    }
+
     Import-LocalizedData `
         -BaseDirectory (Get-IcingaFrameworkRootPath) `
         -FileName 'icinga-powershell-framework.psd1' `
@@ -285,6 +310,14 @@ function Invoke-IcingaCommand()
         Write-IcingaFrameworkCodeCache -DeveloperMode:$DeveloperMode;
     }
 
+    # Try to re-import everything within the same instance
+    if ($NoNewInstance) {
+        Import-IcingaForWindowsModules;
+        Use-Icinga;
+
+        return;
+    }
+
     if ($null -ne $psISE) {
         Use-Icinga;
         Write-IcingaConsoleError -Message 'Icinga for Windows was loaded, but the Icinga Management Console is not available within the PowerShell ISE context. Please start a regular PowerShell to use it.';