Merge pull request #574 from anvilistas/messaging-logger

Add default null logger to messaging

CHANGELOG.md

@@ -9,6 +9,13 @@
 ## Enhancements
 * tabs - tab color can now be a css var and better support for css colors in general
   https://github.com/anvilistas/anvil-extras/pull/570
+* messaging - support custom loggers in messaging module
+  https://github.com/anvilistas/anvil-extras/issues/569
+
+## Deprecations
+- messaging - with_logging argument is deprecated and maybe removed in a future version
+  logging messages is now off by default - to turn it on provide a custom `logger` argument
+  https://github.com/anvilistas/anvil-extras/pull/572/files
 
 # v3.0.0
 

client_code/messaging.py

@@ -5,14 +5,17 @@
 #
 # This software is published at https://github.com/anvilistas/anvil-extras
 
-from logging import INFO
-from logging import Logger as _Logger
-
+from .logging import INFO
+from .logging import Logger as _Logger
 from .utils._warnings import warn as _warn
 
 __version__ = "3.0.0"
 
 
+_null_logger = _Logger()
+_null_logger.disabled = True
+
+
 class Message:
     def __init__(self, title, content=None):
         self.title = title
@@ -26,11 +29,10 @@ def __init__(self, subscriber, handler):
 
 
 class Publisher:
-    default_logger = None
     default_log_level = INFO
 
-    def __init__(self, logger: _Logger = None, **kwargs):
-        self.logger = logger or self.default_logger
+    def __init__(self, *, logger: _Logger = None, **kwargs):
+        self.logger = logger or _null_logger
         self.subscribers = {}
         self._deprecation_warnings(**kwargs)
 
@@ -48,40 +50,36 @@ def publish(self, channel, title, content=None, **kwargs):
         subscribers = self.subscribers.get(channel, [])
         for subscriber in subscribers:
             subscriber.handler(message)
-        if self.logger is not None:
-            self.logger.log(
-                self.default_log_level,
-                f"Published '{message.title}' message on '{channel}' channel to "
-                f"{len(subscribers)} subscriber(s)",
-            )
+        self.logger.log(
+            self.default_log_level,
+            f"Published '{message.title}' message on '{channel}' channel to "
+            f"{len(subscribers)} subscriber(s)",
+        )
 
     def subscribe(self, channel, subscriber, handler, **kwargs):
         self._deprecation_warnings(**kwargs)
         if channel not in self.subscribers:
             self.subscribers[channel] = []
         self.subscribers[channel].append(Subscriber(subscriber, handler))
-        if self.logger is not None:
-            self.logger.log(
-                self.default_log_level, f"Added subscriber to {channel} channel"
-            )
+        self.logger.log(
+            self.default_log_level, f"Added subscriber to {channel} channel"
+        )
 
     def unsubscribe(self, channel, subscriber, **kwargs):
         self._deprecation_warnings(**kwargs)
         if channel in self.subscribers:
             self.subscribers[channel] = [
                 s for s in self.subscribers[channel] if s.subscriber != subscriber
             ]
-        if self.logger is not None:
-            self.logger.log(
-                self.default_log_level, f"Removed subscriber from {channel} channel"
-            )
+        self.logger.log(
+            self.default_log_level, f"Removed subscriber from {channel} channel"
+        )
 
     def close_channel(self, channel, **kwargs):
         self._deprecation_warnings(**kwargs)
         subscribers_count = len(self.subscribers[channel])
         del self.subscribers[channel]
-        if self.logger is not None:
-            self.logger.log(
-                self.default_log_level,
-                f"{channel} closed ({subscribers_count} subscribers)",
-            )
+        self.logger.log(
+            self.default_log_level,
+            f"{channel} closed ({subscribers_count} subscribers)",
+        )