Add hddtemp sensor device even if unreachable. (#10623)

* Add hddtemp sensor device even if unreachable.

* Removed old commented code.

* Move unit detection logic into update.

homeassistant/components/sensor/hddtemp.py

@@ -7,6 +7,7 @@ https://home-assistant.io/components/sensor.hddtemp/
 import logging
 from datetime import timedelta
 from telnetlib import Telnet
+import socket
 
 import voluptuous as vol
 
@@ -46,15 +47,11 @@ def setup_platform(hass, config, add_devices, discovery_info=None):
     hddtemp = HddTempData(host, port)
     hddtemp.update()
 
-    if hddtemp.data is None:
-        return False
-
     if not disks:
         disks = [next(iter(hddtemp.data)).split('|')[0]]
 
     dev = []
     for disk in disks:
-        if disk in hddtemp.data:
         dev.append(HddTempSensor(name, disk, hddtemp))
 
     add_devices(dev, True)
@@ -70,6 +67,7 @@ class HddTempSensor(Entity):
         self._name = '{} {}'.format(name, disk)
         self._state = None
         self._details = None
+        self._unit = None
 
     @property
     def name(self):
@@ -84,13 +82,12 @@ class HddTempSensor(Entity):
     @property
     def unit_of_measurement(self):
         """Return the unit the value is expressed in."""
-        if self._details[3] == 'C':
+        return self._unit
-            return TEMP_CELSIUS
-        return TEMP_FAHRENHEIT
 
     @property
     def device_state_attributes(self):
         """Return the state attributes of the sensor."""
+        if self._details is not None:
             return {
                 ATTR_DEVICE: self._details[0],
                 ATTR_MODEL: self._details[1],
@@ -103,6 +100,10 @@ class HddTempSensor(Entity):
         if self.hddtemp.data and self.disk in self.hddtemp.data:
             self._details = self.hddtemp.data[self.disk].split('|')
             self._state = self._details[2]
+            if self._details is not None and self._details[3] == 'F':
+                self._unit = TEMP_FAHRENHEIT
+            else:
+                self._unit = TEMP_CELSIUS
         else:
             self._state = None
 
@@ -126,6 +127,9 @@ class HddTempData(object):
             self.data = {data[i].split('|')[0]: data[i]
                          for i in range(0, len(data), 1)}
         except ConnectionRefusedError:
-            _LOGGER.error(
+            _LOGGER.error("HDDTemp is not available at %s:%s",
-                "HDDTemp is not available at %s:%s", self.host, self.port)
+                          self.host, self.port)
+            self.data = None
+        except socket.gaierror:
+            _LOGGER.error("HDDTemp host not found %s:%s", self.host, self.port)
             self.data = None

tests/components/sensor/test_hddtemp.py

@@ -1,4 +1,6 @@
 """The tests for the hddtemp platform."""
+import socket
+
 import unittest
 from unittest.mock import patch
 
@@ -56,6 +58,13 @@ VALID_CONFIG_HOST = {
     }
 }
 
+VALID_CONFIG_HOST_UNREACHABLE = {
+    'sensor': {
+        'platform': 'hddtemp',
+        'host': 'bob.local',
+    }
+}
+
 
 class TelnetMock():
     """Mock class for the telnetlib.Telnet object."""
@@ -75,6 +84,8 @@ class TelnetMock():
         """Return sample values."""
         if self.host == 'alice.local':
             raise ConnectionRefusedError
+        elif self.host == 'bob.local':
+            raise socket.gaierror
         else:
             return self.sample_data
         return None
@@ -161,7 +172,10 @@ class TestHDDTempSensor(unittest.TestCase):
         """Test hddtemp wrong disk configuration."""
         assert setup_component(self.hass, 'sensor', VALID_CONFIG_WRONG_DISK)
 
-        self.assertEqual(len(self.hass.states.all()), 0)
+        self.assertEqual(len(self.hass.states.all()), 1)
+        state = self.hass.states.get('sensor.hd_temperature_devsdx1')
+        self.assertEqual(state.attributes.get('friendly_name'),
+                         'HD Temperature ' + '/dev/sdx1')
 
     @patch('telnetlib.Telnet', new=TelnetMock)
     def test_hddtemp_multiple_disks(self):
@@ -189,7 +203,14 @@ class TestHDDTempSensor(unittest.TestCase):
                              'HD Temperature ' + reference['device'])
 
     @patch('telnetlib.Telnet', new=TelnetMock)
-    def test_hddtemp_host_unreachable(self):
+    def test_hddtemp_host_refused(self):
         """Test hddtemp if host unreachable."""
         assert setup_component(self.hass, 'sensor', VALID_CONFIG_HOST)
         self.assertEqual(len(self.hass.states.all()), 0)
+
+    @patch('telnetlib.Telnet', new=TelnetMock)
+    def test_hddtemp_host_unreachable(self):
+        """Test hddtemp if host unreachable."""
+        assert setup_component(self.hass, 'sensor',
+                               VALID_CONFIG_HOST_UNREACHABLE)
+        self.assertEqual(len(self.hass.states.all()), 0)