feat: Add Get-ConnectMgDefault function to retrieve Microsoft Graph authentication record

Author: SamErde

Microsoft 365/Get-ConnectMgDefault.ps1

@@ -0,0 +1,41 @@
+function Get-ConnectMgDefault {
+    <#
+    .SYNOPSIS
+    Returns the default Microsoft Graph authentication record stored in the current user's .mg folder.
+
+    .DESCRIPTION
+    Loads the Microsoft Graph CLI authentication record from "$HOME/.mg/mg.authrecord.json" and presents it as a custom object. This helps you inspect which account and tenant are used by default when connecting with Microsoft Graph.
+
+    .EXAMPLE
+    Get-ConnectMgDefault
+
+    Retrieves the default Microsoft Graph authentication record.
+
+    .EXAMPLE
+    Get-ConnectMgDefault | Select-Object Account, TenantId, Scopes
+
+    Returns only the most commonly reviewed fields from the authentication record.
+
+    .INPUTS
+    None. You cannot pipe objects to this cmdlet.
+
+    .OUTPUTS
+    PSCustomObject. Returns the contents of 'mg.authrecord.json' as a custom object, or $null if the file cannot be read.
+
+    .NOTES
+    Author:   Sam Erde, Sentinel Technologies Inc.
+    Modified: 2025 Dec 15
+    #>
+    [CmdletBinding()]
+    [OutputType('PSCustomObject')]
+    param ()
+
+    try {
+        $DotMgPath = Join-Path -Path (Resolve-Path -Path $HOME).Path -ChildPath '.mg'
+        $AuthRecordPath = Join-Path -Path $DotMgPath -ChildPath 'mg.authrecord.json'
+        Get-Content -Path $AuthRecordPath | ConvertFrom-Json
+    } catch {
+        Write-Warning "Unable to read '$AuthRecordPath'. $($_.Exception.Message)"
+        return $null
+    }
+}