Initial Commit

lib/logutils/adapter.py

@@ -0,0 +1,116 @@
+#
+# Copyright (C) 2010-2013 Vinay Sajip. See LICENSE.txt for details.
+#
+import logging
+import logutils
+
+class LoggerAdapter(object):
+    """
+    An adapter for loggers which makes it easier to specify contextual
+    information in logging output.
+    """
+
+    def __init__(self, logger, extra):
+        """
+        Initialize the adapter with a logger and a dict-like object which
+        provides contextual information. This constructor signature allows
+        easy stacking of LoggerAdapters, if so desired.
+
+        You can effectively pass keyword arguments as shown in the
+        following example:
+
+        adapter = LoggerAdapter(someLogger, dict(p1=v1, p2="v2"))
+        """
+        self.logger = logger
+        self.extra = extra
+
+    def process(self, msg, kwargs):
+        """
+        Process the logging message and keyword arguments passed in to
+        a logging call to insert contextual information. You can either
+        manipulate the message itself, the keyword args or both. Return
+        the message and kwargs modified (or not) to suit your needs.
+
+        Normally, you'll only need to override this one method in a
+        LoggerAdapter subclass for your specific needs.
+        """
+        kwargs["extra"] = self.extra
+        return msg, kwargs
+
+    #
+    # Boilerplate convenience methods
+    #
+    def debug(self, msg, *args, **kwargs):
+        """
+        Delegate a debug call to the underlying logger.
+        """
+        self.log(logging.DEBUG, msg, *args, **kwargs)
+
+    def info(self, msg, *args, **kwargs):
+        """
+        Delegate an info call to the underlying logger.
+        """
+        self.log(logging.INFO, msg, *args, **kwargs)
+
+    def warning(self, msg, *args, **kwargs):
+        """
+        Delegate a warning call to the underlying logger.
+        """
+        self.log(logging.WARNING, msg, *args, **kwargs)
+
+    warn = warning
+
+    def error(self, msg, *args, **kwargs):
+        """
+        Delegate an error call to the underlying logger.
+        """
+        self.log(logging.ERROR, msg, *args, **kwargs)
+
+    def exception(self, msg, *args, **kwargs):
+        """
+        Delegate an exception call to the underlying logger.
+        """
+        kwargs["exc_info"] = 1
+        self.log(logging.ERROR, msg, *args, **kwargs)
+
+    def critical(self, msg, *args, **kwargs):
+        """
+        Delegate a critical call to the underlying logger.
+        """
+        self.log(logging.CRITICAL, msg, *args, **kwargs)
+
+    def log(self, level, msg, *args, **kwargs):
+        """
+        Delegate a log call to the underlying logger, after adding
+        contextual information from this adapter instance.
+        """
+        if self.isEnabledFor(level):
+            msg, kwargs = self.process(msg, kwargs)
+            self.logger._log(level, msg, args, **kwargs)
+
+    def isEnabledFor(self, level):
+        """
+        Is this logger enabled for level 'level'?
+        """
+        if self.logger.manager.disable >= level:
+            return False
+        return level >= self.getEffectiveLevel()
+
+    def setLevel(self, level):
+        """
+        Set the specified level on the underlying logger.
+        """
+        self.logger.setLevel(level)
+
+    def getEffectiveLevel(self):
+        """
+        Get the effective level for the underlying logger.
+        """
+        return self.logger.getEffectiveLevel()
+
+    def hasHandlers(self):
+        """
+        See if the underlying logger has any handlers.
+        """
+        return logutils.hasHandlers(self.logger)
+