Added Push Camera (#15151)

* Added push camera

* add camera.push

* Address comments and add tests

* auff auff

* trip time made no sense

* travis lint

* Mock dependency

* hound

* long line

* long line

* better mocking

* remove blank image

* no more need to mock dependency

* remove import

* cleanup

* no longer needed

* unused constant

* address @pvizeli review

* add force_update

* Revert "add force_update"

This reverts commit e203785ea8.

* rename parameter

homeassistant/components/camera/push.py

@@ -0,0 +1,162 @@
+"""
+Camera platform that receives images through HTTP POST.
+
+For more details about this platform, please refer to the documentation
+https://home-assistant.io/components/camera.push/
+"""
+import logging
+
+from collections import deque
+from datetime import timedelta
+import voluptuous as vol
+
+from homeassistant.components.camera import Camera, PLATFORM_SCHEMA,\
+    STATE_IDLE, STATE_RECORDING
+from homeassistant.core import callback
+from homeassistant.components.http.view import HomeAssistantView
+from homeassistant.const import CONF_NAME, CONF_TIMEOUT, HTTP_BAD_REQUEST
+from homeassistant.helpers import config_validation as cv
+from homeassistant.helpers.event import async_track_point_in_utc_time
+import homeassistant.util.dt as dt_util
+
+_LOGGER = logging.getLogger(__name__)
+
+CONF_BUFFER_SIZE = 'buffer'
+CONF_IMAGE_FIELD = 'field'
+
+DEFAULT_NAME = "Push Camera"
+
+ATTR_FILENAME = 'filename'
+ATTR_LAST_TRIP = 'last_trip'
+
+PLATFORM_SCHEMA = PLATFORM_SCHEMA.extend({
+    vol.Optional(CONF_NAME, default=DEFAULT_NAME): cv.string,
+    vol.Optional(CONF_BUFFER_SIZE, default=1): cv.positive_int,
+    vol.Optional(CONF_TIMEOUT, default=timedelta(seconds=5)): vol.All(
+        cv.time_period, cv.positive_timedelta),
+    vol.Optional(CONF_IMAGE_FIELD, default='image'): cv.string,
+})
+
+
+async def async_setup_platform(hass, config, async_add_devices,
+                               discovery_info=None):
+    """Set up the Push Camera platform."""
+    cameras = [PushCamera(config[CONF_NAME],
+                          config[CONF_BUFFER_SIZE],
+                          config[CONF_TIMEOUT])]
+
+    hass.http.register_view(CameraPushReceiver(cameras,
+                                               config[CONF_IMAGE_FIELD]))
+
+    async_add_devices(cameras)
+
+
+class CameraPushReceiver(HomeAssistantView):
+    """Handle pushes from remote camera."""
+
+    url = "/api/camera_push/{entity_id}"
+    name = 'api:camera_push:camera_entity'
+
+    def __init__(self, cameras, image_field):
+        """Initialize CameraPushReceiver with camera entity."""
+        self._cameras = cameras
+        self._image = image_field
+
+    async def post(self, request, entity_id):
+        """Accept the POST from Camera."""
+        try:
+            (_camera,) = [camera for camera in self._cameras
+                          if camera.entity_id == entity_id]
+        except ValueError:
+            _LOGGER.error("Unknown push camera %s", entity_id)
+            return self.json_message('Unknown Push Camera',
+                                     HTTP_BAD_REQUEST)
+
+        try:
+            data = await request.post()
+            _LOGGER.debug("Received Camera push: %s", data[self._image])
+            await _camera.update_image(data[self._image].file.read(),
+                                       data[self._image].filename)
+        except ValueError as value_error:
+            _LOGGER.error("Unknown value %s", value_error)
+            return self.json_message('Invalid POST', HTTP_BAD_REQUEST)
+        except KeyError as key_error:
+            _LOGGER.error('In your POST message %s', key_error)
+            return self.json_message('{} missing'.format(self._image),
+                                     HTTP_BAD_REQUEST)
+
+
+class PushCamera(Camera):
+    """The representation of a Push camera."""
+
+    def __init__(self, name, buffer_size, timeout):
+        """Initialize push camera component."""
+        super().__init__()
+        self._name = name
+        self._last_trip = None
+        self._filename = None
+        self._expired_listener = None
+        self._state = STATE_IDLE
+        self._timeout = timeout
+        self.queue = deque([], buffer_size)
+        self._current_image = None
+
+    @property
+    def state(self):
+        """Current state of the camera."""
+        return self._state
+
+    async def update_image(self, image, filename):
+        """Update the camera image."""
+        if self._state == STATE_IDLE:
+            self._state = STATE_RECORDING
+            self._last_trip = dt_util.utcnow()
+            self.queue.clear()
+
+        self._filename = filename
+        self.queue.appendleft(image)
+
+        @callback
+        def reset_state(now):
+            """Set state to idle after no new images for a period of time."""
+            self._state = STATE_IDLE
+            self._expired_listener = None
+            _LOGGER.debug("Reset state")
+            self.async_schedule_update_ha_state()
+
+        if self._expired_listener:
+            self._expired_listener()
+
+        self._expired_listener = async_track_point_in_utc_time(
+            self.hass, reset_state, dt_util.utcnow() + self._timeout)
+
+        self.async_schedule_update_ha_state()
+
+    async def async_camera_image(self):
+        """Return a still image response."""
+        if self.queue:
+            if self._state == STATE_IDLE:
+                self.queue.rotate(1)
+            self._current_image = self.queue[0]
+
+        return self._current_image
+
+    @property
+    def name(self):
+        """Return the name of this camera."""
+        return self._name
+
+    @property
+    def motion_detection_enabled(self):
+        """Camera Motion Detection Status."""
+        return False
+
+    @property
+    def device_state_attributes(self):
+        """Return the state attributes."""
+        return {
+            name: value for name, value in (
+                (ATTR_LAST_TRIP, self._last_trip),
+                (ATTR_FILENAME, self._filename),
+            ) if value is not None
+        }