correct MQTT subscription filter

homeassistant/components/mqtt/__init__.py

@@ -11,6 +11,7 @@
 import time
 import ssl
 import requests.certs
+import re
 
 import voluptuous as vol
 
@@ -639,12 +640,20 @@ def _raise_on_error(result):
 
 def _match_topic(subscription, topic):
     """Test if topic matches subscription."""
+    reg_ex_parts = []
+    suffix = ""
     if subscription.endswith('#'):
-        return (subscription[:-2] == topic or
-                topic.startswith(subscription[:-1]))
-
+        subscription = subscription[:-2]
+        suffix = "(.*)"
     sub_parts = subscription.split('/')
-    topic_parts = topic.split('/')
+    for sub_part in sub_parts:
+        if sub_part == "+":
+            reg_ex_parts.append("([^\/]+)")
+        else:
+            reg_ex_parts.append(sub_part)
+
+    reg_ex = "^" + ('\/'.join(reg_ex_parts)) + suffix + "$"
+
+    reg = re.compile(reg_ex)
 
-    return (len(sub_parts) == len(topic_parts) and
-            all(a == b for a, b in zip(sub_parts, topic_parts) if a != '+'))
+    return reg.match(topic) is not None

tests/components/mqtt/test_init.py

@@ -209,6 +209,46 @@ def test_subscribe_topic_subtree_wildcard_no_match(self):
         self.hass.block_till_done()
         self.assertEqual(0, len(self.calls))
 
+    def test_subscribe_topic_level_wildcard_and_wildcard_root_topic(self):
+        """Test the subscription of wildcard topics."""
+        mqtt.subscribe(self.hass, '+/test-topic/#', self.record_calls)
+
+        fire_mqtt_message(self.hass, 'hello/test-topic', 'test-payload')
+
+        self.hass.block_till_done()
+        self.assertEqual(1, len(self.calls))
+        self.assertEqual('hello/test-topic', self.calls[0][0])
+        self.assertEqual('test-payload', self.calls[0][1])
+
+    def test_subscribe_topic_level_wildcard_and_wildcard_subtree_topic(self):
+        """Test the subscription of wildcard topics."""
+        mqtt.subscribe(self.hass, '+/test-topic/#', self.record_calls)
+
+        fire_mqtt_message(self.hass, 'hello/test-topic/here-iam', 'test-payload')
+
+        self.hass.block_till_done()
+        self.assertEqual(1, len(self.calls))
+        self.assertEqual('hello/test-topic/here-iam', self.calls[0][0])
+        self.assertEqual('test-payload', self.calls[0][1])
+
+    def test_subscribe_topic_level_wildcard_and_wildcard_level_wildcard_no_match(self):
+        """Test the subscription of wildcard topics."""
+        mqtt.subscribe(self.hass, '+/test-topic/#', self.record_calls)
+
+        fire_mqtt_message(self.hass, 'hello/here-iam/test-topic', 'test-payload')
+
+        self.hass.block_till_done()
+        self.assertEqual(0, len(self.calls))
+
+    def test_subscribe_topic_level_wildcard_and_wildcard_no_match(self):
+        """Test the subscription of wildcard topics."""
+        mqtt.subscribe(self.hass, '+/test-topic/#', self.record_calls)
+
+        fire_mqtt_message(self.hass, 'hello/another-test-topic', 'test-payload')
+
+        self.hass.block_till_done()
+        self.assertEqual(0, len(self.calls))
+
     def test_subscribe_binary_topic(self):
         """Test the subscription to a binary topic."""
         mqtt.subscribe(self.hass, 'test-topic', self.record_calls,