Added the ability to Weather Underground to track severe weather alerts (#3505)

*  Added the ability to Weather Underground to track severe weather alerts

*   * Added message on the advisory attr

  * Updated tests

* * Making use of guard clause

* Checking multiple_alerts prior loop

* Using a better way to create dict

* Fixed issue to set to None only the object that failed

* Added unittest

* Split update() method to different calls with their one throttle control to minimize API calls

* Updated unittest and make sure the alert sensor will not return 'unknown' status'

* Removed update() method from state property

* Branch rebased and include Weather Underground attribution

* Update wunderground.py

tests/components/sensor/test_wunderground.py

@@ -11,7 +11,7 @@ VALID_CONFIG_PWS = {
     'api_key': 'foo',
     'pws_id': 'bar',
     'monitored_conditions': [
-        'weather', 'feelslike_c'
+        'weather', 'feelslike_c', 'alerts'
     ]
 }
 
@@ -19,17 +19,19 @@ VALID_CONFIG = {
     'platform': 'wunderground',
     'api_key': 'foo',
     'monitored_conditions': [
-        'weather', 'feelslike_c'
+        'weather', 'feelslike_c', 'alerts'
     ]
 }
 
 FEELS_LIKE = '40'
 WEATHER = 'Clear'
 ICON_URL = 'http://icons.wxug.com/i/c/k/clear.gif'
+ALERT_MESSAGE = 'This is a test alert message'
 
 
 def mocked_requests_get(*args, **kwargs):
     """Mock requests.get invocations."""
+    # pylint: disable=too-few-public-methods
     class MockResponse:
         """Class to represent a mocked response."""
 
@@ -61,26 +63,36 @@ def mocked_requests_get(*args, **kwargs):
                 "feelslike_c": FEELS_LIKE,
                 "weather": WEATHER,
                 "icon_url": ICON_URL
-            }
+            }, "alerts": [
+                {
+                    "type": 'FLO',
+                    "description": "Areal Flood Warning",
+                    "date": "9:36 PM CDT on September 22, 2016",
+                    "expires": "10:00 AM CDT on September 23, 2016",
+                    "message": ALERT_MESSAGE,
+                },
+
+            ],
         }, 200)
     else:
         return MockResponse({
-                "response": {
-                    "version": "0.1",
-                    "termsofService":
-                        "http://www.wunderground.com/weather/api/d/terms.html",
-                    "features": {},
-                    "error": {
-                        "type": "keynotfound",
-                        "description": "this key does not exist"
-                    }
+            "response": {
+                "version": "0.1",
+                "termsofService":
+                    "http://www.wunderground.com/weather/api/d/terms.html",
+                "features": {},
+                "error": {
+                    "type": "keynotfound",
+                    "description": "this key does not exist"
                 }
-            }, 200)
+            }
+        }, 200)
 
 
 class TestWundergroundSetup(unittest.TestCase):
     """Test the WUnderground platform."""
 
+    # pylint: disable=invalid-name
     DEVICES = []
 
     def add_devices(self, devices):
@@ -107,14 +119,13 @@ class TestWundergroundSetup(unittest.TestCase):
                                         self.add_devices, None))
         self.assertTrue(
             wunderground.setup_platform(self.hass, VALID_CONFIG,
-                                        self.add_devices,
-                                        None))
+                                        self.add_devices, None))
         invalid_config = {
             'platform': 'wunderground',
             'api_key': 'BOB',
             'pws_id': 'bar',
             'monitored_conditions': [
-                'weather', 'feelslike_c'
+                'weather', 'feelslike_c', 'alerts'
             ]
         }
 
@@ -128,11 +139,17 @@ class TestWundergroundSetup(unittest.TestCase):
         wunderground.setup_platform(self.hass, VALID_CONFIG, self.add_devices,
                                     None)
         for device in self.DEVICES:
+            device.update()
             self.assertTrue(str(device.name).startswith('PWS_'))
             if device.name == 'PWS_weather':
                 self.assertEqual(ICON_URL, device.entity_picture)
                 self.assertEqual(WEATHER, device.state)
                 self.assertIsNone(device.unit_of_measurement)
+            elif device.name == 'PWS_alerts':
+                self.assertEqual(1, device.state)
+                self.assertEqual(ALERT_MESSAGE,
+                                 device.device_state_attributes['Message'])
+                self.assertIsNone(device.entity_picture)
             else:
                 self.assertIsNone(device.entity_picture)
                 self.assertEqual(FEELS_LIKE, device.state)