Make name optional

Allows using the identity module option if no name was specified.
Currently name must be set with state=present but identity will be used
if no name was specified.

changelogs/fragments/search-by-identity.yml

@@ -0,0 +1,4 @@
+minor_changes:
+- Make ``name`` an optional parameter for the AD modules. Either ``name`` or ``identity`` needs to be set with their
+  respective behaviours. If creating a new AD user and only ``identity`` is set, that will be the value used for the
+  name of the object.

plugins/doc_fragments/ad_object.py

@@ -111,7 +111,7 @@ class ModuleDocFragment:
     - The C(name) of the AD object to manage.
     - If I(identity) is specified, and the name of the object it found does not
       match this value, the object will be renamed.
-    - This must be set when I(state=present) or if I(identity) is not set.
+    - This if I(identity) must be set to find the object to manage.
     - This is not always going to be the same as the C(sAMAccountName) for user
       objects. It is strictly the C(name) of the object in the path specified.
       Use I(identity) to select an object to manage by C(sAMAccountName).

plugins/module_utils/_ADObject.psm1

@@ -740,7 +740,7 @@ Function Invoke-AnsibleADObject {
     }
 
     $stateRequiredIf = @{
-        present = @('name')
+        present = @()
         absent = @()
     }
 
@@ -905,9 +905,15 @@ Function Invoke-AnsibleADObject {
         $objectGuid = $null
 
         if (-not $adObject) {
+            $adName = if ($module.Params.name) {
+                $module.Params.name
+            }
+            else {
+                $module.Params.identity
+            }
             $newParams = @{
                 Confirm = $false
-                Name = $module.Params.name
+                Name = $adName
                 WhatIf = $module.CheckMode
                 PassThru = $true
             }
@@ -926,7 +932,7 @@ Function Invoke-AnsibleADObject {
 
             $module.Diff.after = @{
                 attributes = $diffAttributes.after
-                name = $module.Params.name
+                name = $adName
                 path = $objectPath
             }
 
@@ -985,7 +991,7 @@ Function Invoke-AnsibleADObject {
             $module.Result.changed = $true
 
             if ($module.CheckMode) {
-                $objectDN = "$namePrefix=$($module.Params.name -replace ',', '\,'),$objectPath"
+                $objectDN = "$namePrefix=$($adName -replace ',', '\,'),$objectPath"
                 $objectGuid = [Guid]::Empty  # Dummy value for check mode
             }
             else {
@@ -1075,8 +1081,9 @@ Function Invoke-AnsibleADObject {
             }
 
             $finalADObject = $null
-            if ($module.Params.name -cne $objectName) {
-                $objectName = $module.Params.name
+            $desiredName = $module.Params.name
+            if ($desiredName -and $desiredName -cne $objectName) {
+                $objectName = $desiredName
                 $module.Diff.after.name = $objectName
 
                 $finalADObject = Rename-ADObject @commonParams @adParams -NewName $objectName