Z-Wave prevent I/O event loop (#6369)

* Prevent Z-Wave I/O in event loop

* Move value_handler to util class.

* Add docstring

homeassistant/components/zwave/__init__.py

@@ -26,6 +26,7 @@ import homeassistant.helpers.config_validation as cv
 
 from . import const
 from . import workaround
+from .util import value_handler
 
 REQUIREMENTS = ['pydispatcher==2.0.5']
 
@@ -729,8 +730,11 @@ class ZWaveDeviceEntity(Entity):
         from pydispatch import dispatcher
         self._value = value
         self._value.set_change_verified(False)
-        self.entity_id = "{}.{}".format(domain, self._object_id())
+        self.entity_id = "{}.{}".format(domain, object_id(value))
 
+        self._name = _value_name(self._value)
+        self._unique_id = "ZWAVE-{}-{}".format(self._value.node.node_id,
+                                               self._value.object_id)
         self._wakeup_value_id = None
         self._battery_value_id = None
         self._power_value_id = None
@@ -816,62 +820,13 @@ class ZWaveDeviceEntity(Entity):
         self.power_consumption = round(
             power_value.data, power_value.precision) if power_value else None
 
-    def _value_handler(self, method=None, class_id=None, index=None,
-                       label=None, data=None, member=None, instance=None,
-                       **kwargs):
-        """Get the values for a given command_class with arguments.
-
-        May only be used inside callback.
-
-        """
-        values = []
-        if class_id is None:
-            values.extend(self._value.node.get_values(**kwargs).values())
-        else:
-            if not isinstance(class_id, list):
-                class_id = [class_id]
-            for cid in class_id:
-                values.extend(self._value.node.get_values(
-                    class_id=cid, **kwargs).values())
-        _LOGGER.debug('method=%s, class_id=%s, index=%s, label=%s, data=%s,'
-                      ' member=%s, instance=%d, kwargs=%s',
-                      method, class_id, index, label, data, member, instance,
-                      kwargs)
-        _LOGGER.debug('values=%s', values)
-        results = None
-        for value in values:
-            if index is not None and value.index != index:
-                continue
-            if label is not None:
-                label_found = False
-                for entry in label:
-                    if value.label == entry:
-                        label_found = True
-                        break
-                if not label_found:
-                    continue
-            if method == 'set':
-                value.data = data
-                return
-            if data is not None and value.data != data:
-                continue
-            if instance is not None and value.instance != instance:
-                continue
-            if member is not None:
-                results = getattr(value, member)
-            else:
-                results = value
-            break
-        _LOGGER.debug('final result=%s', results)
-        return results
-
     def get_value(self, **kwargs):
         """Simplifyer to get values. May only be used inside callback."""
-        return self._value_handler(method='get', **kwargs)
+        return value_handler(self._value, method='get', **kwargs)
 
     def set_value(self, **kwargs):
         """Simplifyer to set a value."""
-        return self._value_handler(method='set', **kwargs)
+        return value_handler(self._value, method='set', **kwargs)
 
     def update_properties(self):
         """Callback on data changes for node values."""
@@ -885,21 +840,12 @@ class ZWaveDeviceEntity(Entity):
     @property
     def unique_id(self):
         """Return an unique ID."""
-        return "ZWAVE-{}-{}".format(self._value.node.node_id,
-                                    self._value.object_id)
+        return self._unique_id
 
     @property
     def name(self):
         """Return the name of the device."""
-        return _value_name(self._value)
-
-    def _object_id(self):
-        """Return the object_id of the device value.
-
-        The object_id contains node_id and value instance id to not collide
-        with other entity_ids.
-        """
-        return object_id(self._value)
+        return self._name
 
     @property
     def device_state_attributes(self):

homeassistant/components/zwave/util.py

@@ -0,0 +1,54 @@
+"""Zwave util methods."""
+import logging
+
+_LOGGER = logging.getLogger(__name__)
+
+
+def value_handler(value, method=None, class_id=None, index=None,
+                  label=None, data=None, member=None, instance=None,
+                  **kwargs):
+    """Get the values for a given command_class with arguments.
+
+    May only be used inside callback.
+
+    """
+    values = []
+    if class_id is None:
+        values.extend(value.node.get_values(**kwargs).values())
+    else:
+        if not isinstance(class_id, list):
+            class_id = [class_id]
+        for cid in class_id:
+            values.extend(value.node.get_values(
+                class_id=cid, **kwargs).values())
+    _LOGGER.debug('method=%s, class_id=%s, index=%s, label=%s, data=%s,'
+                  ' member=%s, instance=%d, kwargs=%s',
+                  method, class_id, index, label, data, member, instance,
+                  kwargs)
+    _LOGGER.debug('values=%s', values)
+    results = None
+    for value in values:
+        if index is not None and value.index != index:
+            continue
+        if label is not None:
+            label_found = False
+            for entry in label:
+                if value.label == entry:
+                    label_found = True
+                    break
+            if not label_found:
+                continue
+        if method == 'set':
+            value.data = data
+            return
+        if data is not None and value.data != data:
+            continue
+        if instance is not None and value.instance != instance:
+            continue
+        if member is not None:
+            results = getattr(value, member)
+        else:
+            results = value
+        break
+    _LOGGER.debug('final result=%s', results)
+    return results