Handle multiple intents with the same name (#2921)

* Add check for duplicate adapt intents

There are two cases, duplicated named intent and duplicated anonymous intent.

A named intent will cause a ValueError exception notifying the skill
author that there is a collision.

An anonymous intent will silently derive a new name and use that
instead of the default generated one.

* Add tests for intent collisions

* Make enable/disable intent handle the new exception

The enable/disable intent did not mark an intent as detached, instead it
remained in the list of intents after disabling in the IntentServiceInterface
to be retrieved when the intent should be re-enabled.

This moves detached intents into a list of detached intents to so they
won't cause the double enable exception.

* Add move logic to find if intent is detached

MycroftSkill.enable_intent() will now check if the intent is detached
before trying to re-enable it.

* Lock updates of intents

This should avoid some race conditions that may occur if multiple
threads tries to enable / disable intents

mycroft/skills/intent_service_interface.py

@@ -35,6 +35,7 @@ class IntentServiceInterface:
     def __init__(self, bus=None):
         self.bus = bus
         self.registered_intents = []
+        self.detached_intents = []
 
     def set_bus(self, bus):
         self.bus = bus
@@ -83,14 +84,40 @@ def register_adapt_intent(self, name, intent_parser):
         """
         self.bus.emit(Message("register_intent", intent_parser.__dict__))
         self.registered_intents.append((name, intent_parser))
+        self.detached_intents = [detached for detached in self.detached_intents
+                                 if detached[0] != name]
 
     def detach_intent(self, intent_name):
         """Remove an intent from the intent service.
 
+        The intent is saved in the list of detached intents for use when
+        re-enabling an intent.
+
         Args:
             intent_name(str): Intent reference
         """
-        self.bus.emit(Message("detach_intent", {"intent_name": intent_name}))
+        name = intent_name.split(':')[1]
+        if name in self:
+            self.bus.emit(Message("detach_intent",
+                                  {"intent_name": intent_name}))
+            self.detached_intents.append((name, self.get_intent(name)))
+            self.registered_intents = [pair for pair in self.registered_intents
+                                       if pair[0] != name]
+
+    def intent_is_detached(self, intent_name):
+        """Determine if an intent is detached.
+
+        Args:
+            intent_name(str): Intent reference
+
+        Returns:
+            (bool) True if intent is found, else False.
+        """
+        for (name, _) in self.detached_intents:
+            if name == intent_name:
+                return True
+
+        return False
 
     def set_adapt_context(self, context, word, origin):
         """Set an Adapt context.
@@ -161,6 +188,8 @@ def __contains__(self, val):
     def get_intent(self, intent_name):
         """Get intent from intent_name.
 
+        This will find both enabled and disabled intents.
+
         Args:
             intent_name (str): name to find.
 
@@ -170,8 +199,10 @@ def get_intent(self, intent_name):
         for name, intent in self:
             if name == intent_name:
                 return intent
-        else:
-            return None
+        for name, intent in self.detached_intents:
+            if name == intent_name:
+                return intent
+        return None
 
 
 class IntentQueryApi:

mycroft/skills/mycroft_skill/mycroft_skill.py

@@ -22,7 +22,7 @@
 from os import walk
 from os.path import join, abspath, dirname, basename, exists
 from pathlib import Path
-from threading import Event, Timer
+from threading import Event, Timer, Lock
 
 from xdg import BaseDirectory
 
@@ -161,6 +161,7 @@ def __init__(self, name=None, bus=None, use_settings=True):
         # Delegator classes
         self.event_scheduler = EventSchedulerInterface(self.name)
         self.intent_service = IntentServiceInterface()
+        self.intent_service_lock = Lock()
 
         # Skill Public API
         self.public_api = {}
@@ -364,9 +365,10 @@ def handle_settings_change(self, message):
                     self.settings_change_callback()
 
     def detach(self):
-        for (name, _) in self.intent_service:
-            name = '{}:{}'.format(self.skill_id, name)
-            self.intent_service.detach_intent(name)
+        with self.intent_service_lock:
+            for (name, _) in self.intent_service:
+                name = '{}:{}'.format(self.skill_id, name)
+                self.intent_service.detach_intent(name)
 
     def initialize(self):
         """Perform any final setup needed for the skill.
@@ -958,21 +960,46 @@ def remove_event(self, name):
     def _register_adapt_intent(self, intent_parser, handler):
         """Register an adapt intent.
 
+        Will handle registration of anonymous
         Args:
             intent_parser: Intent object to parse utterance for the handler.
             handler (func): function to register with intent
         """
         # Default to the handler's function name if none given
+        is_anonymous = not intent_parser.name
         name = intent_parser.name or handler.__name__
+        if is_anonymous:
+            # Find a good name
+            original_name = name
+            nbr = 0
+            while name in self.intent_service:
+                nbr += 1
+                name = f'{original_name}{nbr}'
+        else:
+            if name in self.intent_service:
+                raise ValueError(f'The intent name {name} is already taken')
+
         munge_intent_parser(intent_parser, name, self.skill_id)
         self.intent_service.register_adapt_intent(name, intent_parser)
+
         if handler:
             self.add_event(intent_parser.name, handler,
                            'mycroft.skill.handler')
 
     def register_intent(self, intent_parser, handler):
         """Register an Intent with the intent service.
 
+        Args:
+            intent_parser: Intent, IntentBuilder object or padatious intent
+                           file to parse utterance for the handler.
+            handler (func): function to register with intent
+        """
+        with self.intent_service_lock:
+            self._register_intent(intent_parser, handler)
+
+    def _register_intent(self, intent_parser, handler):
+        """Register an Intent with the intent service.
+
         Args:
             intent_parser: Intent, IntentBuilder object or padatious intent
                            file to parse utterance for the handler.
@@ -1019,6 +1046,7 @@ def register_intent_file(self, intent_file, handler):
         filename = self.find_resource(intent_file, 'vocab')
         if not filename:
             raise FileNotFoundError('Unable to find "{}"'.format(intent_file))
+
         self.intent_service.register_padatious_intent(name, filename)
         if handler:
             self.add_event(name, handler, 'mycroft.skill.handler')
@@ -1047,23 +1075,20 @@ def register_entity_file(self, entity_file):
             raise FileNotFoundError('Unable to find "{}"'.format(entity_file))
 
         name = '{}:{}'.format(self.skill_id, entity_file)
-        self.intent_service.register_padatious_entity(name, filename)
+        with self.intent_service_lock:
+            self.intent_service.register_padatious_entity(name, filename)
 
     def handle_enable_intent(self, message):
         """Listener to enable a registered intent if it belongs to this skill.
         """
         intent_name = message.data['intent_name']
-        for (name, _) in self.intent_service:
-            if name == intent_name:
-                return self.enable_intent(intent_name)
+        return self.enable_intent(intent_name)
 
     def handle_disable_intent(self, message):
         """Listener to disable a registered intent if it belongs to this skill.
         """
         intent_name = message.data['intent_name']
-        for (name, _) in self.intent_service:
-            if name == intent_name:
-                return self.disable_intent(intent_name)
+        self.disable_intent(intent_name)
 
     def disable_intent(self, intent_name):
         """Disable a registered intent if it belongs to this skill.
@@ -1074,15 +1099,16 @@ def disable_intent(self, intent_name):
         Returns:
                 bool: True if disabled, False if it wasn't registered
         """
-        if intent_name in self.intent_service:
-            LOG.debug('Disabling intent ' + intent_name)
-            name = '{}:{}'.format(self.skill_id, intent_name)
-            self.intent_service.detach_intent(name)
-            return True
-        else:
-            LOG.error('Could not disable '
-                      '{}, it hasn\'t been registered.'.format(intent_name))
-            return False
+        with self.intent_service_lock:
+            if intent_name in self.intent_service:
+                LOG.info('Disabling intent ' + intent_name)
+                name = '{}:{}'.format(self.skill_id, intent_name)
+                self.intent_service.detach_intent(name)
+                return True
+            else:
+                LOG.error('Could not disable '
+                          f'{intent_name}, it hasn\'t been registered.')
+                return False
 
     def enable_intent(self, intent_name):
         """(Re)Enable a registered intent if it belongs to this skill.
@@ -1094,17 +1120,21 @@ def enable_intent(self, intent_name):
             bool: True if enabled, False if it wasn't registered
         """
         intent = self.intent_service.get_intent(intent_name)
-        if intent:
-            if ".intent" in intent_name:
-                self.register_intent_file(intent_name, None)
+        with self.intent_service_lock:
+            if intent and self.intent_service.intent_is_detached(intent_name):
+                if ".intent" in intent_name:
+                    self.register_intent_file(intent_name, None)
+                else:
+                    intent.name = intent_name
+                    self._register_intent(intent, None)
+                LOG.debug('Enabling intent {}'.format(intent_name))
+                return True
+            elif intent:
+                LOG.error(f'Could not enable {intent_name}, '
+                          'it\'s not detached')
             else:
-                intent.name = intent_name
-                self.register_intent(intent, None)
-            LOG.debug('Enabling intent {}'.format(intent_name))
-            return True
-        else:
-            LOG.error('Could not enable '
-                      '{}, it hasn\'t been registered.'.format(intent_name))
+                LOG.error('Could not enable '
+                          f'{intent_name}, it hasn\'t been registered.')
             return False
 
     def set_context(self, context, word='', origin=''):
@@ -1169,7 +1199,8 @@ def register_vocabulary(self, entity, entity_type):
             entity_type:    Intent handler entity to tie the word to
         """
         keyword_type = to_alnum(self.skill_id) + entity_type
-        self.intent_service.register_adapt_keyword(keyword_type, entity)
+        with self.intent_service_lock:
+            self.intent_service.register_adapt_keyword(keyword_type, entity)
 
     def register_regex(self, regex_str):
         """Register a new regex.
@@ -1179,7 +1210,8 @@ def register_regex(self, regex_str):
         self.log.debug('registering regex string: ' + regex_str)
         regex = munge_regex(regex_str, self.skill_id)
         re.compile(regex)  # validate regex
-        self.intent_service.register_adapt_regex(regex)
+        with self.intent_service_lock:
+            self.intent_service.register_adapt_regex(regex)
 
     def speak(self, utterance, expect_response=False, wait=False, meta=None):
         """Speak a sentence.
@@ -1295,9 +1327,10 @@ def load_vocab_files(self, root_directory):
             for line in keywords[vocab_type]:
                 entity = line[0]
                 aliases = line[1:]
-                self.intent_service.register_adapt_keyword(vocab_type,
-                                                           entity,
-                                                           aliases)
+                with self.intent_service_lock:
+                    self.intent_service.register_adapt_keyword(vocab_type,
+                                                               entity,
+                                                               aliases)
 
     def load_regex_files(self, root_directory):
         """ Load regex files found under the skill directory.
@@ -1314,7 +1347,8 @@ def load_regex_files(self, root_directory):
             regexes = load_regex(locale_dir, self.skill_id)
 
         for regex in regexes:
-            self.intent_service.register_adapt_regex(regex)
+            with self.intent_service_lock:
+                self.intent_service.register_adapt_regex(regex)
 
     def __handle_stop(self, _):
         """Handler for the "mycroft.stop" signal. Runs the user defined

test/unittests/skills/test_mycroft_skill.py

@@ -27,7 +27,8 @@
 from mycroft.messagebus.message import Message
 from mycroft.skills.skill_data import (load_regex_from_file, load_regex,
                                        load_vocabulary, read_vocab_file)
-from mycroft.skills.core import MycroftSkill, resting_screen_handler
+from mycroft.skills import (MycroftSkill, resting_screen_handler,
+                            intent_handler)
 from mycroft.skills.intent_service import open_intent_envelope
 
 from test.util import base_config
@@ -628,6 +629,23 @@ def test_speak_dialog_render_not_initialized(self):
         s.speak_dialog(key='key')
 
 
+class TestIntentCollisions(unittest.TestCase):
+    def test_two_intents_with_same_name(self):
+        emitter = MockEmitter()
+        skill = SameIntentNameSkill()
+        skill.bind(emitter)
+        with self.assertRaises(ValueError):
+            skill.initialize()
+
+    def test_two_anonymous_intent_decorators(self):
+        """Two anonymous intent handlers should be ok."""
+        emitter = MockEmitter()
+        skill = SameAnonymousIntentDecoratorsSkill()
+        skill.bind(emitter)
+        skill._register_decorated()
+        self.assertEqual(len(skill.intent_service.registered_intents), 2)
+
+
 class _TestSkill(MycroftSkill):
     def __init__(self):
         super().__init__()
@@ -705,3 +723,27 @@ def initialize(self):
 
     def handler(self, message):
         pass
+
+
+class SameIntentNameSkill(_TestSkill):
+    """Test skill for duplicate intent namesr."""
+    skill_id = 'A'
+
+    def initialize(self):
+        intent = IntentBuilder('TheName').require('Keyword')
+        intent2 = IntentBuilder('TheName').require('Keyword')
+        self.register_intent(intent, self.handler)
+        self.register_intent(intent2, self.handler)
+
+    def handler(self, message):
+        pass
+
+
+class SameAnonymousIntentDecoratorsSkill(_TestSkill):
+    """Test skill for duplicate anonymous intent handlers."""
+    skill_id = 'A'
+
+    @intent_handler(IntentBuilder('').require('Keyword'))
+    @intent_handler(IntentBuilder('').require('OtherKeyword'))
+    def handler(self, message):
+        pass