Expose all components on hass [Concept] (#8490)

* Add components concept

* Lint

* Raise ImportError if component not found

homeassistant/components/light/__init__.py

@@ -13,6 +13,7 @@ import csv
 import voluptuous as vol
 
 from homeassistant.core import callback
+from homeassistant.loader import bind_hass
 from homeassistant.components import group
 from homeassistant.config import load_yaml_config_file
 from homeassistant.const import (
@@ -165,6 +166,7 @@ def turn_on(hass, entity_id=None, transition=None, brightness=None,
 
 
 @callback
+@bind_hass
 def async_turn_on(hass, entity_id=None, transition=None, brightness=None,
                   brightness_pct=None, rgb_color=None, xy_color=None,
                   color_temp=None, kelvin=None, white_value=None,

homeassistant/core.py

@@ -30,6 +30,7 @@ from homeassistant.const import (
     EVENT_SERVICE_EXECUTED, EVENT_SERVICE_REGISTERED, EVENT_STATE_CHANGED,
     EVENT_TIME_CHANGED, MATCH_ALL, EVENT_HOMEASSISTANT_CLOSE,
     EVENT_SERVICE_REMOVED, __version__)
+from homeassistant.loader import Components
 from homeassistant.exceptions import (
     HomeAssistantError, InvalidEntityFormatError)
 from homeassistant.util.async import (
@@ -128,6 +129,7 @@ class HomeAssistant(object):
         self.services = ServiceRegistry(self)
         self.states = StateMachine(self.bus, self.loop)
         self.config = Config()  # type: Config
+        self.components = Components(self)
         # This is a dictionary that any component can store any data on.
         self.data = {}
         self.state = CoreState.not_running

homeassistant/loader.py

@@ -10,6 +10,7 @@ call get_component('switch.your_platform'). In both cases the config directory
 is checked to see if it contains a user provided version. If not available it
 will check the built-in components and platforms.
 """
+import functools as ft
 import importlib
 import logging
 import os
@@ -170,6 +171,49 @@ def get_component(comp_name) -> Optional[ModuleType]:
     return None
 
 
+class Components:
+    """Helper to load components."""
+
+    def __init__(self, hass):
+        """Initialize the Components class."""
+        self._hass = hass
+
+    def __getattr__(self, comp_name):
+        """Fetch a component."""
+        component = get_component(comp_name)
+        if component is None:
+            raise ImportError('Unable to load {}'.format(comp_name))
+        wrapped = ComponentWrapper(self._hass, component)
+        setattr(self, comp_name, wrapped)
+        return wrapped
+
+
+class ComponentWrapper:
+    """Class to wrap a component and auto fill in hass argument."""
+
+    def __init__(self, hass, component):
+        """Initialize the component wrapper."""
+        self._hass = hass
+        self._component = component
+
+    def __getattr__(self, attr):
+        """Fetch an attribute."""
+        value = getattr(self._component, attr)
+
+        if hasattr(value, '__bind_hass'):
+            value = ft.partial(value, self._hass)
+
+        setattr(self, attr, value)
+        return value
+
+
+def bind_hass(func):
+    """Decorator to indicate that first argument is hass."""
+    # pylint: disable=protected-access
+    func.__bind_hass = True
+    return func
+
+
 def load_order_component(comp_name: str) -> OrderedSet:
     """Return an OrderedSet of components in the correct order of loading.
 

tests/test_loader.py

@@ -1,11 +1,15 @@
 """Test to verify that we can load components."""
 # pylint: disable=protected-access
+import asyncio
 import unittest
 
+import pytest
+
 import homeassistant.loader as loader
 import homeassistant.components.http as http
 
-from tests.common import get_test_home_assistant, MockModule
+from tests.common import (
+    get_test_home_assistant, MockModule, async_mock_service)
 
 
 class TestLoader(unittest.TestCase):
@@ -54,3 +58,29 @@ class TestLoader(unittest.TestCase):
 
         # Try to get load order for non-existing component
         self.assertEqual([], loader.load_order_component('mod1'))
+
+
+def test_component_loader(hass):
+    """Test loading components."""
+    components = loader.Components(hass)
+    assert components.http.CONFIG_SCHEMA is http.CONFIG_SCHEMA
+    assert hass.components.http.CONFIG_SCHEMA is http.CONFIG_SCHEMA
+
+
+def test_component_loader_non_existing(hass):
+    """Test loading components."""
+    components = loader.Components(hass)
+    with pytest.raises(ImportError):
+        components.non_existing
+
+
+@asyncio.coroutine
+def test_component_wrapper(hass):
+    """Test component wrapper."""
+    calls = async_mock_service(hass, 'light', 'turn_on')
+
+    components = loader.Components(hass)
+    components.light.async_turn_on('light.test')
+    yield from hass.async_block_till_done()
+
+    assert len(calls) == 1