Add dispatcher camera for internal image. (#6471)

* Add dispatcher camera for internal image.

* fix lint

* Add unittest

* Update dispatcher.py

homeassistant/components/camera/dispatcher.py

@@ -0,0 +1,67 @@
+"""
+Support for internal dispatcher image push to Camera.
+
+For more details about this platform, please refer to the documentation at
+https://home-assistant.io/components/camera.dispatcher/
+"""
+import asyncio
+import logging
+
+import voluptuous as vol
+
+from homeassistant.core import callback
+from homeassistant.const import CONF_NAME
+from homeassistant.components.camera import PLATFORM_SCHEMA, Camera
+from homeassistant.helpers import config_validation as cv
+from homeassistant.helpers.dispatcher import async_dispatcher_connect
+
+_LOGGER = logging.getLogger(__name__)
+
+CONF_SIGNAL = 'signal'
+DEFAULT_NAME = 'Dispatcher Camera'
+
+PLATFORM_SCHEMA = PLATFORM_SCHEMA.extend({
+    vol.Required(CONF_SIGNAL): cv.slugify,
+    vol.Optional(CONF_NAME, default=DEFAULT_NAME): cv.string,
+})
+
+
+@asyncio.coroutine
+def async_setup_platform(hass, config, async_add_devices, discovery_info=None):
+    """Setup a dispatcher camera."""
+    if discovery_info:
+        config = PLATFORM_SCHEMA(discovery_info)
+
+    async_add_devices(
+        [DispatcherCamera(config[CONF_NAME], config[CONF_SIGNAL])])
+
+
+class DispatcherCamera(Camera):
+    """A dispatcher implementation of an camera."""
+
+    def __init__(self, name, signal):
+        """Initialize a dispatcher camera."""
+        super().__init__()
+        self._name = name
+        self._signal = signal
+        self._image = None
+
+    @asyncio.coroutine
+    def async_added_to_hass(self):
+        """Register dispatcher and callbacks."""
+        @callback
+        def async_update_image(image):
+            """Update image from dispatcher call."""
+            self._image = image
+
+        async_dispatcher_connect(self.hass, self._signal, async_update_image)
+
+    @asyncio.coroutine
+    def async_camera_image(self):
+        """Return a still image response from the camera."""
+        return self._image
+
+    @property
+    def name(self):
+        """Return the name of this device."""
+        return self._name

tests/components/camera/test_dispatcher.py

@@ -0,0 +1,36 @@
+"""The tests for dispatcher camera component."""
+import asyncio
+
+from homeassistant.setup import async_setup_component
+from homeassistant.helpers.dispatcher import async_dispatcher_send
+
+
+@asyncio.coroutine
+def test_run_camera_setup(hass, test_client):
+    """Test that it fetches the given dispatcher data."""
+    yield from async_setup_component(hass, 'camera', {
+        'camera': {
+            'platform': 'dispatcher',
+            'name': 'dispatcher',
+            'signal': 'test_camera',
+        }})
+
+    client = yield from test_client(hass.http.app)
+
+    async_dispatcher_send(hass, 'test_camera', b'test')
+    yield from hass.async_block_till_done()
+
+    resp = yield from client.get('/api/camera_proxy/camera.dispatcher')
+
+    assert resp.status == 200
+    body = yield from resp.text()
+    assert body == 'test'
+
+    async_dispatcher_send(hass, 'test_camera', b'test2')
+    yield from hass.async_block_till_done()
+
+    resp = yield from client.get('/api/camera_proxy/camera.dispatcher')
+
+    assert resp.status == 200
+    body = yield from resp.text()
+    assert body == 'test2'