Include Regional Site Name Availability Check for DNL site creations

Author: nineela

src/azure-cli/azure/cli/command_modules/appservice/_create_util.py

@@ -334,6 +334,18 @@ def get_site_availability(cmd, name):
                                 "cannot start or end in a hyphen, and must be less than 64 chars.")
     return availability
 
+def get_regional_site_availability(cmd, location, name, resource_group_name, auto_generated_domain_name_label_scope):
+    client = web_client_factory(cmd.cli_ctx)
+    availability = client.regional_check_name_availability(location, name, "Site", resource_group_name, auto_generated_domain_name_label_scope)
+
+    # check for "." in app name. it is valid for hostnames to contain it, but not allowed for webapp names
+    if "." in name:
+        availability.name_available = False
+        availability.reason = "Invalid"
+        availability.message = ("Site names only allow alphanumeric characters and hyphens, "
+                                "cannot start or end in a hyphen, and must be less than 64 chars.")
+    return availability
+
 
 def get_app_details(cmd, name):
     client = web_client_factory(cmd.cli_ctx)

src/azure-cli/azure/cli/command_modules/appservice/custom.py

@@ -75,7 +75,7 @@
                     _remove_list_duplicates, get_raw_functionapp,
                     register_app_provider)
 from ._create_util import (zip_contents_from_dir, get_runtime_version_details, create_resource_group, get_app_details,
-                           check_resource_group_exists, set_location, get_site_availability, get_profile_username,
+                           check_resource_group_exists, set_location, get_site_availability, get_regional_site_availability, get_profile_username,
                            get_plan_to_use, get_lang_from_content, get_rg_to_use, get_sku_to_use,
                            detect_os_from_src, get_current_stack_from_runtime, generate_default_app_name,
                            get_or_create_default_workspace, get_or_create_default_resource_group,
@@ -167,7 +167,12 @@ def create_webapp(cmd, resource_group_name, name, plan, runtime=None, startup_fi
     helper = _StackRuntimeHelper(cmd, linux=is_linux, windows=not is_linux)
     location = plan_info.location
     # This is to keep the existing appsettings for a newly created webapp on existing webapp name.
-    name_validation = get_site_availability(cmd, name)
+
+    if auto_generated_domain_name_label_scope:
+        name_validation = get_regional_site_availability(cmd, location, name, resource_group_name, auto_generated_domain_name_label_scope)
+    else:
+        name_validation = get_site_availability(cmd, name)
+
     if not name_validation.name_available:
         if name_validation.reason == 'Invalid':
             raise ValidationError(name_validation.message)