app: Introduce API to setup an app

Like the earlier API, accept old_version as parameter. A base implementation,
simply call setup on all components.

Signed-off-by: Sunil Mohan Adapa <sunil@medhas.org>
Reviewed-by: James Valleroy <jvalleroy@mailbox.org>

plinth/app.py

@@ -113,6 +113,11 @@ class App:
         """
         return self.get_component(self.app_id + '-info')
 
+    def setup(self, old_version):
+        """Install and configure the app and its components."""
+        for component in self.components.values():
+            component.setup(old_version=old_version)
+
     def enable(self):
         """Enable all the components of the app."""
         for component in self.components.values():
@@ -221,6 +226,9 @@ class Component:
         """
         return App.get(self.app_id)
 
+    def setup(self, old_version):
+        """Run operations to install and configure the component."""
+
     def enable(self):
         """Run operations to enable the component."""
 

plinth/tests/test_app.py

@@ -4,7 +4,7 @@ Test module for App, base class for all applications.
 """
 
 import collections
-from unittest.mock import patch
+from unittest.mock import Mock, call, patch
 
 import pytest
 
@@ -114,6 +114,16 @@ def test_get_components_of_type(app_with_components):
     assert list(components) == leader_components
 
 
+def test_app_setup(app_with_components):
+    """Test that running setup on an app run setup on components."""
+    for component in app_with_components.components.values():
+        component.setup = Mock()
+
+    app_with_components.setup(old_version=2)
+    for component in app_with_components.components.values():
+        component.setup.assert_has_calls([call(old_version=2)])
+
+
 def test_app_enable(app_with_components):
     """Test that enabling an app enables components."""
     app_with_components.disable()
@@ -222,6 +232,24 @@ def test_component_app_property():
     assert component.app == app
 
 
+def test_component_setup():
+    """Test running setup on component."""
+    component = Component('test-component')
+    assert component.setup(old_version=1) is None
+
+
+def test_component_enable():
+    """Test running enable on component."""
+    component = Component('test-component')
+    assert component.enable() is None
+
+
+def test_component_disable():
+    """Test running disable on component."""
+    component = Component('test-component')
+    assert component.disable() is None
+
+
 def test_component_diagnose():
     """Test running diagnostics on component."""
     component = Component('test-component')