Use Redis instead of an in-process map to store the entity/plugin registry

This is particularly useful when we want to access the registry from
another process, like the web server or an external script.

platypush/entities/__init__.py

@@ -1,15 +1,16 @@
 import warnings
 from typing import Collection, Optional
 
-from ._base import Entity
+from ._base import Entity, get_entities_registry
 from ._engine import EntitiesEngine
-from ._registry import manages, register_entity_plugin, get_plugin_registry
+from ._registry import manages, register_entity_plugin, get_plugin_entity_registry
 
 _engine: Optional[EntitiesEngine] = None
 
 
 def init_entities_engine() -> EntitiesEngine:
     from ._base import init_entities_db
+
     global _engine
     init_entities_db()
     _engine = EntitiesEngine()
@@ -24,13 +25,14 @@ def publish_entities(entities: Collection[Entity]):
 
     _engine.post(*entities)
 
+
 __all__ = (
     'Entity',
     'EntitiesEngine',
     'init_entities_engine',
     'publish_entities',
     'register_entity_plugin',
-    'get_plugin_registry',
+    'get_plugin_entity_registry',
+    'get_entities_registry',
     'manages',
 )
-

platypush/entities/_registry.py

@@ -1,24 +1,38 @@
+import json
 from datetime import datetime
-from typing import Optional, Mapping, Dict, Collection, Type
+from typing import Optional, Dict, Collection, Type
 
 from platypush.plugins import Plugin
-from platypush.utils import get_plugin_name_by_class
+from platypush.utils import get_plugin_name_by_class, get_redis
 
 from ._base import Entity
 
-_entity_plugin_registry: Mapping[Type[Entity], Dict[str, Plugin]] = {}
+_entity_registry_varname = '_platypush/plugin_entity_registry'
 
 
 def register_entity_plugin(entity_type: Type[Entity], plugin: Plugin):
-    plugins = _entity_plugin_registry.get(entity_type, {})
+    plugin_name = get_plugin_name_by_class(plugin.__class__) or ''
-    plugin_name = get_plugin_name_by_class(plugin.__class__)
+    entity_type_name = entity_type.__name__.lower()
-    assert plugin_name
+    redis = get_redis()
-    plugins[plugin_name] = plugin
+    registry = get_plugin_entity_registry()
-    _entity_plugin_registry[entity_type] = plugins
+    registry_by_plugin = set(registry['by_plugin'].get(plugin_name, []))
+
+    registry_by_entity_type = set(registry['by_entity_type'].get(entity_type_name, []))
+
+    registry_by_plugin.add(entity_type_name)
+    registry_by_entity_type.add(plugin_name)
+    registry['by_plugin'][plugin_name] = list(registry_by_plugin)
+    registry['by_entity_type'][entity_type_name] = list(registry_by_entity_type)
+    redis.mset({_entity_registry_varname: json.dumps(registry)})
 
 
-def get_plugin_registry():
+def get_plugin_entity_registry() -> Dict[str, Dict[str, Collection[str]]]:
-    return _entity_plugin_registry.copy()
+    redis = get_redis()
+    registry = redis.mget([_entity_registry_varname])[0]
+    try:
+        return json.loads((registry or b'').decode())
+    except (TypeError, ValueError):
+        return {'by_plugin': {}, 'by_entity_type': {}}
 
 
 class EntityManagerMixin:
@@ -37,6 +51,7 @@ class EntityManagerMixin:
 
     def publish_entities(self, entities: Optional[Collection[Entity]]):
         from . import publish_entities
+
         entities = self.transform_entities(entities)
         publish_entities(entities)
 
@@ -59,4 +74,3 @@ def manages(*entities: Type[Entity]):
         return plugin
 
     return wrapper
-

platypush/utils/__init__.py

@@ -1,4 +1,5 @@
 import ast
+import contextlib
 import datetime
 import hashlib
 import importlib
@@ -20,8 +21,8 @@ logger = logging.getLogger('utils')
 
 
 def get_module_and_method_from_action(action):
-    """ Input  : action=music.mpd.play
+    """Input  : action=music.mpd.play
-        Output : ('music.mpd', 'play') """
+    Output : ('music.mpd', 'play')"""
 
     tokens = action.split('.')
     module_name = str.join('.', tokens[:-1])
@@ -30,7 +31,7 @@ def get_module_and_method_from_action(action):
 
 
 def get_message_class_by_type(msgtype):
-    """ Gets the class of a message type given as string """
+    """Gets the class of a message type given as string"""
 
     try:
         module = importlib.import_module('platypush.message.' + msgtype)
@@ -43,8 +44,7 @@ def get_message_class_by_type(msgtype):
     try:
         msgclass = getattr(module, cls_name)
     except AttributeError as e:
-        logger.warning('No such class in {}: {}'.format(
+        logger.warning('No such class in {}: {}'.format(module.__name__, cls_name))
-            module.__name__, cls_name))
         raise RuntimeError(e)
 
     return msgclass
@@ -52,13 +52,13 @@ def get_message_class_by_type(msgtype):
 
 # noinspection PyShadowingBuiltins
 def get_event_class_by_type(type):
-    """ Gets an event class by type name """
+    """Gets an event class by type name"""
     event_module = importlib.import_module('.'.join(type.split('.')[:-1]))
     return getattr(event_module, type.split('.')[-1])
 
 
 def get_plugin_module_by_name(plugin_name):
-    """ Gets the module of a plugin by name (e.g. "music.mpd" or "media.vlc") """
+    """Gets the module of a plugin by name (e.g. "music.mpd" or "media.vlc")"""
 
     module_name = 'platypush.plugins.' + plugin_name
     try:
@@ -69,22 +69,26 @@ def get_plugin_module_by_name(plugin_name):
 
 
 def get_plugin_class_by_name(plugin_name):
-    """ Gets the class of a plugin by name (e.g. "music.mpd" or "media.vlc") """
+    """Gets the class of a plugin by name (e.g. "music.mpd" or "media.vlc")"""
 
     module = get_plugin_module_by_name(plugin_name)
     if not module:
         return
 
-    class_name = getattr(module, ''.join([_.capitalize() for _ in plugin_name.split('.')]) + 'Plugin')
+    class_name = getattr(
+        module, ''.join([_.capitalize() for _ in plugin_name.split('.')]) + 'Plugin'
+    )
     try:
-        return getattr(module, ''.join([_.capitalize() for _ in plugin_name.split('.')]) + 'Plugin')
+        return getattr(
+            module, ''.join([_.capitalize() for _ in plugin_name.split('.')]) + 'Plugin'
+        )
     except Exception as e:
         logger.error('Cannot import class {}: {}'.format(class_name, str(e)))
         return None
 
 
 def get_plugin_name_by_class(plugin) -> Optional[str]:
-    """Gets the common name of a plugin (e.g. "music.mpd" or "media.vlc") given its class. """
+    """Gets the common name of a plugin (e.g. "music.mpd" or "media.vlc") given its class."""
 
     from platypush.plugins import Plugin
 
@@ -93,7 +97,8 @@ def get_plugin_name_by_class(plugin) -> Optional[str]:
 
     class_name = plugin.__name__
     class_tokens = [
-        token.lower() for token in re.sub(r'([A-Z])', r' \1', class_name).split(' ')
+        token.lower()
+        for token in re.sub(r'([A-Z])', r' \1', class_name).split(' ')
         if token.strip() and token != 'Plugin'
     ]
 
@@ -101,7 +106,7 @@ def get_plugin_name_by_class(plugin) -> Optional[str]:
 
 
 def get_backend_name_by_class(backend) -> Optional[str]:
-    """Gets the common name of a backend (e.g. "http" or "mqtt") given its class. """
+    """Gets the common name of a backend (e.g. "http" or "mqtt") given its class."""
 
     from platypush.backend import Backend
 
@@ -110,7 +115,8 @@ def get_backend_name_by_class(backend) -> Optional[str]:
 
     class_name = backend.__name__
     class_tokens = [
-        token.lower() for token in re.sub(r'([A-Z])', r' \1', class_name).split(' ')
+        token.lower()
+        for token in re.sub(r'([A-Z])', r' \1', class_name).split(' ')
         if token.strip() and token != 'Backend'
     ]
 
@@ -135,12 +141,12 @@ def set_timeout(seconds, on_timeout):
 
 
 def clear_timeout():
-    """ Clear any previously set timeout """
+    """Clear any previously set timeout"""
     signal.alarm(0)
 
 
 def get_hash(s):
-    """ Get the SHA256 hash hex digest of a string input """
+    """Get the SHA256 hash hex digest of a string input"""
     return hashlib.sha256(s.encode('utf-8')).hexdigest()
 
 
@@ -177,11 +183,8 @@ def get_decorators(cls, climb_class_hierarchy=False):
     node_iter.visit_FunctionDef = visit_FunctionDef
 
     for target in targets:
-        try:
+        with contextlib.suppress(TypeError):
             node_iter.visit(ast.parse(inspect.getsource(target)))
-        except TypeError:
-            # Ignore built-in classes
-            pass
 
     return decorators
 
@@ -195,45 +198,57 @@ def get_redis_queue_name_by_message(msg):
     return 'platypush/responses/{}'.format(msg.id) if msg.id else None
 
 
-def _get_ssl_context(context_type=None, ssl_cert=None, ssl_key=None,
+def _get_ssl_context(
-                     ssl_cafile=None, ssl_capath=None):
+    context_type=None, ssl_cert=None, ssl_key=None, ssl_cafile=None, ssl_capath=None
+):
     if not context_type:
-        ssl_context = ssl.create_default_context(cafile=ssl_cafile,
+        ssl_context = ssl.create_default_context(cafile=ssl_cafile, capath=ssl_capath)
-                                                 capath=ssl_capath)
     else:
         ssl_context = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
 
     if ssl_cafile or ssl_capath:
-        ssl_context.load_verify_locations(
+        ssl_context.load_verify_locations(cafile=ssl_cafile, capath=ssl_capath)
-            cafile=ssl_cafile, capath=ssl_capath)
 
     ssl_context.load_cert_chain(
         certfile=os.path.abspath(os.path.expanduser(ssl_cert)),
-        keyfile=os.path.abspath(os.path.expanduser(ssl_key)) if ssl_key else None
+        keyfile=os.path.abspath(os.path.expanduser(ssl_key)) if ssl_key else None,
     )
 
     return ssl_context
 
 
-def get_ssl_context(ssl_cert=None, ssl_key=None, ssl_cafile=None,
+def get_ssl_context(ssl_cert=None, ssl_key=None, ssl_cafile=None, ssl_capath=None):
-                    ssl_capath=None):
+    return _get_ssl_context(
-    return _get_ssl_context(context_type=None,
+        context_type=None,
-                            ssl_cert=ssl_cert, ssl_key=ssl_key,
+        ssl_cert=ssl_cert,
-                            ssl_cafile=ssl_cafile, ssl_capath=ssl_capath)
+        ssl_key=ssl_key,
+        ssl_cafile=ssl_cafile,
+        ssl_capath=ssl_capath,
+    )
 
 
-def get_ssl_server_context(ssl_cert=None, ssl_key=None, ssl_cafile=None,
+def get_ssl_server_context(
-                           ssl_capath=None):
+    ssl_cert=None, ssl_key=None, ssl_cafile=None, ssl_capath=None
-    return _get_ssl_context(context_type=ssl.PROTOCOL_TLS_SERVER,
+):
-                            ssl_cert=ssl_cert, ssl_key=ssl_key,
+    return _get_ssl_context(
-                            ssl_cafile=ssl_cafile, ssl_capath=ssl_capath)
+        context_type=ssl.PROTOCOL_TLS_SERVER,
+        ssl_cert=ssl_cert,
+        ssl_key=ssl_key,
+        ssl_cafile=ssl_cafile,
+        ssl_capath=ssl_capath,
+    )
 
 
-def get_ssl_client_context(ssl_cert=None, ssl_key=None, ssl_cafile=None,
+def get_ssl_client_context(
-                           ssl_capath=None):
+    ssl_cert=None, ssl_key=None, ssl_cafile=None, ssl_capath=None
-    return _get_ssl_context(context_type=ssl.PROTOCOL_TLS_CLIENT,
+):
-                            ssl_cert=ssl_cert, ssl_key=ssl_key,
+    return _get_ssl_context(
-                            ssl_cafile=ssl_cafile, ssl_capath=ssl_capath)
+        context_type=ssl.PROTOCOL_TLS_CLIENT,
+        ssl_cert=ssl_cert,
+        ssl_key=ssl_key,
+        ssl_cafile=ssl_cafile,
+        ssl_capath=ssl_capath,
+    )
 
 
 def set_thread_name(name):
@@ -241,6 +256,7 @@ def set_thread_name(name):
 
     try:
         import prctl
+
         # noinspection PyUnresolvedReferences
         prctl.set_name(name)
     except ImportError:
@@ -251,9 +267,9 @@ def find_bins_in_path(bin_name):
     return [
         os.path.join(p, bin_name)
         for p in os.environ.get('PATH', '').split(':')
-        if os.path.isfile(os.path.join(p, bin_name)) and (
+        if os.path.isfile(os.path.join(p, bin_name))
-            os.name == 'nt' or os.access(os.path.join(p, bin_name), os.X_OK)
+        and (os.name == 'nt' or os.access(os.path.join(p, bin_name), os.X_OK))
-        )]
+    ]
 
 
 def find_files_by_ext(directory, *exts):
@@ -271,7 +287,7 @@ def find_files_by_ext(directory, *exts):
     max_len = len(max(exts, key=len))
     result = []
 
-    for root, dirs, files in os.walk(directory):
+    for _, __, files in os.walk(directory):
         for i in range(min_len, max_len + 1):
             result += [f for f in files if f[-i:] in exts]
 
@@ -302,8 +318,9 @@ def get_ip_or_hostname():
 
 def get_mime_type(resource):
     import magic
+
     if resource.startswith('file://'):
-        resource = resource[len('file://'):]
+        resource = resource[len('file://') :]
 
     # noinspection HttpUrlsUsage
     if resource.startswith('http://') or resource.startswith('https://'):
@@ -315,7 +332,9 @@ def get_mime_type(resource):
         elif hasattr(magic, 'from_file'):
             mime = magic.from_file(resource, mime=True)
         else:
-            raise RuntimeError('The installed magic version provides neither detect_from_filename nor from_file')
+            raise RuntimeError(
+                'The installed magic version provides neither detect_from_filename nor from_file'
+            )
 
         if mime:
             return mime.mime_type if hasattr(mime, 'mime_type') else mime
@@ -332,6 +351,7 @@ def grouper(n, iterable, fillvalue=None):
     grouper(3, 'ABCDEFG', 'x') --> ABC DEF Gxx
     """
     from itertools import zip_longest
+
     args = [iter(iterable)] * n
 
     if fillvalue:
@@ -355,6 +375,7 @@ def is_functional_cron(obj) -> bool:
 
 def run(action, *args, **kwargs):
     from platypush.context import get_plugin
+
     (module_name, method_name) = get_module_and_method_from_action(action)
     plugin = get_plugin(module_name)
     method = getattr(plugin, method_name)
@@ -366,7 +387,9 @@ def run(action, *args, **kwargs):
     return response.output
 
 
-def generate_rsa_key_pair(key_file: Optional[str] = None, size: int = 2048) -> Tuple[str, str]:
+def generate_rsa_key_pair(
+    key_file: Optional[str] = None, size: int = 2048
+) -> Tuple[str, str]:
     """
     Generate an RSA key pair.
 
@@ -390,27 +413,30 @@ def generate_rsa_key_pair(key_file: Optional[str] = None, size: int = 2048) -> T
 
     public_exp = 65537
     private_key = rsa.generate_private_key(
-        public_exponent=public_exp,
+        public_exponent=public_exp, key_size=size, backend=default_backend()
-        key_size=size,
-        backend=default_backend()
     )
 
     logger.info('Generating RSA {} key pair'.format(size))
     private_key_str = private_key.private_bytes(
         encoding=serialization.Encoding.PEM,
         format=serialization.PrivateFormat.TraditionalOpenSSL,
-        encryption_algorithm=serialization.NoEncryption()
+        encryption_algorithm=serialization.NoEncryption(),
     ).decode()
 
-    public_key_str = private_key.public_key().public_bytes(
+    public_key_str = (
+        private_key.public_key()
+        .public_bytes(
             encoding=serialization.Encoding.PEM,
             format=serialization.PublicFormat.PKCS1,
-    ).decode()
+        )
+        .decode()
+    )
 
     if key_file:
         logger.info('Saving private key to {}'.format(key_file))
-        with open(os.path.expanduser(key_file), 'w') as f1, \
+        with open(os.path.expanduser(key_file), 'w') as f1, open(
-                open(os.path.expanduser(key_file) + '.pub', 'w') as f2:
+            os.path.expanduser(key_file) + '.pub', 'w'
+        ) as f2:
             f1.write(private_key_str)
             f2.write(public_key_str)
             os.chmod(key_file, 0o600)
@@ -426,8 +452,7 @@ def get_or_generate_jwt_rsa_key_pair():
     pub_key_file = priv_key_file + '.pub'
 
     if os.path.isfile(priv_key_file) and os.path.isfile(pub_key_file):
-        with open(pub_key_file, 'r') as f1, \
+        with open(pub_key_file, 'r') as f1, open(priv_key_file, 'r') as f2:
-                open(priv_key_file, 'r') as f2:
             return f1.read(), f2.read()
 
     pathlib.Path(key_dir).mkdir(parents=True, exist_ok=True, mode=0o755)
@@ -439,7 +464,7 @@ def get_enabled_plugins() -> dict:
     from platypush.context import get_plugin
 
     plugins = {}
-    for name, config in Config.get_plugins().items():
+    for name in Config.get_plugins():
         try:
             plugin = get_plugin(name)
             if plugin:
@@ -453,11 +478,18 @@ def get_enabled_plugins() -> dict:
 
 def get_redis() -> Redis:
     from platypush.config import Config
-    return Redis(**(Config.get('backend.redis') or {}).get('redis_args', {}))
+
+    return Redis(
+        **(
+            (Config.get('backend.redis') or {}).get('redis_args', {})
+            or Config.get('redis')
+            or {}
+        )
+    )
 
 
 def to_datetime(t: Union[str, int, float, datetime.datetime]) -> datetime.datetime:
-    if isinstance(t, int) or isinstance(t, float):
+    if isinstance(t, (int, float)):
         return datetime.datetime.fromtimestamp(t, tz=tz.tzutc())
     if isinstance(t, str):
         return parser.parse(t)