[App Service] Update functionapp commands to show warning for Linux consumption EOL and recommend Flex consumption for all consumption apps

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

@@ -23,7 +23,7 @@
 
 from ._validators import (validate_timeout_value, validate_site_create, validate_asp_create,
                           validate_ase_create, validate_ip_address,
-                          validate_service_tag, validate_public_cloud)
+                          validate_service_tag, validate_public_cloud, warn_linux_consumption_eol)
 
 AUTH_TYPES = {
     'AllowAnonymous': 'na',
@@ -94,6 +94,14 @@ def load_arguments(self, _):
                    help="the name of the slot. Default to the productions slot if not specified")
         c.argument('name', arg_type=webapp_name_arg_type)
 
+    with self.argument_context('functionapp') as c:
+        c.ignore('app_instance')
+        c.argument('resource_group_name', arg_type=resource_group_name_type)
+        c.argument('location', arg_type=get_location_type(self.cli_ctx))
+        c.argument('slot', options_list=['--slot', '-s'],
+                   help="the name of the slot. Default to the productions slot if not specified")
+        c.argument('name', arg_type=functionapp_name_arg_type, validator=warn_linux_consumption_eol)
+
     with self.argument_context('appservice') as c:
         c.argument('resource_group_name', arg_type=resource_group_name_type)
         c.argument('location', arg_type=get_location_type(self.cli_ctx))

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

@@ -143,6 +143,7 @@ def validate_functionapp_on_containerapp_site_config_set(cmd, namespace):
         raise ValidationError(
             "Invalid command. This is not supported for Azure Functions on Azure Container app environments.",
             "Please use the following command instead: az functionapp config container set")
+    warn_linux_consumption_eol(cmd, namespace)
 
 
 def validate_functionapp_on_containerapp_container_settings_delete(cmd, namespace):
@@ -162,6 +163,7 @@ def validate_functionapp_on_containerapp_update(cmd, namespace):
         raise ValidationError(
             "Invalid command. This is currently not supported for Azure Functions on Azure Container app environments.",
             "Please use either 'az functionapp config appsettings set' or 'az functionapp config container set'")
+    warn_linux_consumption_eol(cmd, namespace)
 
 
 def validate_functionapp_on_containerapp_site_config_show(cmd, namespace):
@@ -171,6 +173,7 @@ def validate_functionapp_on_containerapp_site_config_show(cmd, namespace):
         raise ValidationError(
             "Invalid command. This is not supported for Azure Functions on Azure Container app environments.",
             "Please use the following command instead: az functionapp config container show")
+    warn_linux_consumption_eol(cmd, namespace)
 
 
 def validate_functionapp_on_flex_plan(cmd, namespace):
@@ -206,6 +209,52 @@ def validate_is_flex_functionapp(cmd, namespace):
         raise ValidationError('This command is only valid for Azure Functions on the FlexConsumption plan.')
 
 
+def warn_linux_consumption_eol(cmd, namespace):
+    """Shows a warning if the function app is on Linux Consumption plan."""
+    from azure.core.exceptions import ResourceNotFoundError as ResNotFoundError, HttpResponseError
+
+    resource_group_name = getattr(namespace, 'resource_group_name', None) or getattr(namespace, 'resource_group', None)
+    name = _get_app_name(namespace)
+    slot = getattr(namespace, 'slot', None)
+    if not name or not resource_group_name:
+        return
+
+    functionapp = None
+    try:
+        functionapp = _generic_site_operation(cmd.cli_ctx, resource_group_name, name, 'get', slot)
+    except (ResNotFoundError, HttpResponseError):
+        # App doesn't exist yet (e.g., during create command) or is inaccessible, skip warning
+        pass
+    if functionapp is None:
+        return
+
+    # Check if Linux (reserved=True) and get the plan
+    is_linux = getattr(functionapp, 'reserved', False)
+    server_farm_id = get_site_server_farm_id(functionapp)
+    if not is_linux or server_farm_id is None:
+        return
+
+    parsed_plan_id = parse_resource_id(server_farm_id)
+    client = web_client_factory(cmd.cli_ctx)
+    plan_info = None
+    try:
+        plan_info = client.app_service_plans.get(parsed_plan_id['resource_group'], parsed_plan_id['name'])
+    except (ResNotFoundError, HttpResponseError):
+        # Plan not found or inaccessible, skip warning
+        pass
+    if plan_info is None or not hasattr(plan_info, 'sku') or plan_info.sku is None:
+        return
+
+    if plan_info.sku.tier == 'Dynamic':
+        logger.warning(
+            "Migrate your app to Flex Consumption as Linux Consumption will reach EOL on "
+            "September 30, 2028 and will no longer be supported. Flex Consumption is now the "
+            "recommended serverless hosting plan for Azure Functions. It offers faster scaling, "
+            "reduced cold starts, private networking, and more control over performance and cost. Help link: "
+            "https://learn.microsoft.com/en-us/azure/azure-functions/migration/migrate-plan-consumption-to-flex"
+        )
+
+
 def validate_app_exists(cmd, namespace):
     app = namespace.name
     resource_group_name = namespace.resource_group_name
@@ -227,6 +276,7 @@ def validate_functionapp_on_containerapp_vnet(cmd, namespace):
         raise ValidationError(
             'Unsupported operation on function app.',
             'Please set virtual network configuration for the function app at Container app environment level.')
+    warn_linux_consumption_eol(cmd, namespace)
 
 
 def validate_add_vnet(cmd, namespace):
@@ -629,6 +679,7 @@ def validate_app_is_functionapp(cmd, namespace):
         raise ValidationError(f"App '{name}' in group '{rg}' is a logic app.")
     if is_webapp(app):
         raise ValidationError(f"App '{name}' in group '{rg}' is a web app.")
+    warn_linux_consumption_eol(cmd, namespace)
 
 
 def validate_centauri_delete_function(cmd, namespace):
@@ -638,6 +689,7 @@ def validate_centauri_delete_function(cmd, namespace):
         raise ValidationError(
             "Invalid Operation. This function is currently present in your image",
             "Please modify your image to remove the function and provide an updated image.")
+    warn_linux_consumption_eol(cmd, namespace)
 
 
 def validate_registry_server(namespace):

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

@@ -8624,6 +8624,28 @@ def create_functionapp(cmd, resource_group_name, name, storage_account, plan=Non
             raise ValidationError("Location is invalid. Use: az functionapp list-flexconsumption-locations")
         is_linux = True
 
+    # Show warnings for Consumption plan (Linux or Windows)
+    # Check if using --consumption-plan-location OR --plan with a consumption SKU (Dynamic tier)
+    plan_sku = getattr(plan_info, 'sku', None) if plan_info else None
+    plan_sku_tier = getattr(plan_sku, 'tier', None)
+    is_consumption_plan = consumption_plan_location is not None or (plan_info and plan_sku_tier == 'Dynamic')
+    if is_consumption_plan:
+        if is_linux:
+            logger.warning(
+                "Linux Consumption will reach EOL on September 30, 2028 and will no longer be supported. "
+                "Flex Consumption is now the recommended serverless hosting plan for Azure Functions. "
+                "It offers faster scaling, reduced cold starts, private networking, and more control over "
+                "performance and cost. Help link: "
+                "https://learn.microsoft.com/en-us/azure/azure-functions/migration/migrate-plan-consumption-to-flex"
+            )
+        else:
+            logger.warning(
+                "Flex Consumption is now the recommended serverless hosting plan for Azure Functions. "
+                "It offers faster scaling, reduced cold starts, private networking, and more control over "
+                "performance and cost. Help link: "
+                "https://learn.microsoft.com/en-us/azure/azure-functions/migration/migrate-plan-consumption-to-flex"
+            )
+
     if environment is not None:
         if consumption_plan_location is not None:
             raise ArgumentUsageError(