Add Blueprint logging support

README.rst

@@ -15,8 +15,16 @@ Flask-Logging-Extras
 
 Flask-Logging-Extras adds additional logging features for Flask applications.
 
-The only feature implemented now is adding extra arguments to the format
-string, like this (this example adds the category keyword to the logs:
+Extra keywords in the log formatters
+------------------------------------
+
+Adding extra keywords to the log format message is a bit tedious, as these
+must be supplied to the logging methods in the `extra` argument as a
+dictionary.
+
+Flask-Logging-Extras makes this easier, so you can add such keywords to the
+logging methods directly. The example adds the category keyword to the logs,
+and shows how to do it with and without Flask-Logging-Extras:
 
 .. code-block:: python
 
@@ -26,9 +34,56 @@ string, like this (this example adds the category keyword to the logs:
    app.config['FLASK_LOGGING_EXTRAS_KEYWORDS'] = {'category': '<unset>'}
    app.logger.init_app(app)
 
+   # Without Flask-Logging-Extras
+   current_app.logger.info('this is a the message, as usual',
+                           extra={'category': 'fancy-category'})
+   # With Flask-Logging-Extras
    current_app.logger.info('this is the message, as usual',
                            category='fancy-category')
 
+Logging the blueprint name
+--------------------------
+
+Although you can always access the blueprint name using `request.blueprint`,
+adding it to the logs as a new keyword is not so easy.
+
+With Flask-Logging-Extras you can specify a keyword that will hold the
+blueprint name in the logs, and specify what value to put there if the log
+doesn’t originate in a request, or it is not from a blueprint route, but
+from an app route.
+
+.. code-block:: python
+
+   fmt = '[%(blueprint)s] %(message)s'
+   # Initialize log handlers as usual, like creating a FileHandler, and
+   # assign fmt to it as a format string
+   app.config['FLASK_LOGGING_EXTRAS_BLUEPRINT'] = (
+       'blueprint',
+       '<APP>',
+       '<NO REQUEST>',
+   )
+
+   bp = Blueprint('bpname', __name__)
+   app.register_blueprint(bp)
+
+   @app.route('/route/1/')
+   def route_1():
+       # This will produce the log message: "[<APP>] Message"
+       current_app.logger.info('Message')
+
+       return 'response 1'
+
+   @bp.route('/route/2/')
+   def route_2():
+       # This will produce the log message: "[bpname] Message"
+       current_app.logger.info('Message')
+
+       return 'response 2'
+
+   def random_function_outside_of_a_request():
+       # This will produce the log message: "[<NO REQUEST>] Message"
+       current_app.logger.info('Message')
+
 Installation
 ------------
 

flask_logging_extras/__init__.py

@@ -32,6 +32,8 @@ no value is present in the message record.
 
 import logging
 
+from flask import has_request_context, request
+
 __version_info__ = ('0', '0', '1')
 __version__ = '.'.join(__version_info__)
 __author__ = 'Gergely Polonkai'
@@ -40,7 +42,8 @@ __copyright__ = '(c) 2015 GT2'
 
 class FlaskExtraLogger(logging.getLoggerClass()):
     """
-    A logger class that is capable of adding extra keywords to log formatters
+    A logger class that is capable of adding extra keywords to log
+    formatters and logging the blueprint name
 
     Usage:
 
@@ -55,8 +58,14 @@ class FlaskExtraLogger(logging.getLoggerClass()):
 
        app = Flask(__name__)
        app.config['FLASK_LOGGING_EXTRAS_KEYWORDS'] = {'category': '<unset>'}
+       app.config['FLASK_LOGGING_EXTRAS_BLUEPRINT'] = ('blueprint',
+                                                       '<APP>',
+                                                       '<NOT REQUEST>')
        app.logger.init_app()
 
+       bp = Blueprint('my_blueprint', __name__)
+       app.register_blueprint(bp)
+
        formatter = logging.Formatter(
            '[%(asctime)s] [%(levelname)s] [%(category)s] %(message)s')
        handler = logging.FileHandler('app.log', mode='a')
@@ -68,9 +77,38 @@ class FlaskExtraLogger(logging.getLoggerClass()):
        app.logger.info('The message', category='my category')
 
        # This will produce something like this in app.log:
-       # [TIMESTAMP2017-01-16 08:44:48.944] [INFO] [my category] The message
+       # [2017-01-16 08:44:48.944] [INFO] [my category] The message
+
+       formatter = logging.Formatter('[%(blueprint)s] %(message)s')
+       handler = logging.FileHandler('other.log', mode='a')
+       handler.setFormatter(formatter)
+       handler.setLevel(logging.INFO)
+
+       app.logger.addHandler(handler)
+
+       @app.route('/1/')
+       def route_1():
+           # This will produce this log message:
+           # [<APP>] Message
+           current_app.logger.info('Message')
+
+           return ''
+
+       @bp.route('/2')
+       def route_2():
+           # This will produce this log message:
+           # [my blueprint] Message
+           current_app.logger.info('Message')
+
+           return ''
+
+       # This will produce this log message:
+       [<NOT REQUEST>] Message
+       app.logger.info('Message')
     """
 
+    _RESERVED_KEYWORDS = ('exc_info', 'extra', 'stack_info')
+
     def __init__(self, *args, **kwargs):
         if 'app' in kwargs:
             if kwargs['app'] is not None:
@@ -84,6 +122,9 @@ class FlaskExtraLogger(logging.getLoggerClass()):
 
         self.app = None
         self._valid_keywords = []
+        self._blueprint_var = None
+        self._blueprint_app = None
+        self._blueprint_norequest = None
 
         super(FlaskExtraLogger, self).__init__(*args, **kwargs)
 
@@ -91,6 +132,13 @@ class FlaskExtraLogger(logging.getLoggerClass()):
         if 'extra' not in kwargs:
             kwargs['extra'] = {}
 
+        # If we were asked to log the blueprint name, add it to the extra list
+        if self._blueprint_var is not None:
+            if has_request_context():
+                kwargs['extra'][self._blueprint_var] = request.blueprint or self._blueprint_app
+            else:
+                kwargs['extra'][self._blueprint_var] = self._blueprint_norequest
+
         for kw in self._valid_keywords:
             if kw in kwargs:
                 kwargs['extra'][kw] = kwargs[kw]
@@ -100,6 +148,13 @@ class FlaskExtraLogger(logging.getLoggerClass()):
 
         super(FlaskExtraLogger, self)._log(*args, **kwargs)
 
+    def _check_reserved_word(self, word):
+        if word in self._RESERVED_KEYWORDS:
+            raise ValueError(
+                '"{keyword}" cannot be used as an extra keyword, as it is '
+                'reserved for internal use.'
+                .format(keyword=word))
+
     def init_app(self, app):
         """
         Intialize the logger class with a Flask application
@@ -118,14 +173,21 @@ class FlaskExtraLogger(logging.getLoggerClass()):
         """
 
         app.config.setdefault('FLASK_LOGGING_EXTRAS_KEYWORDS', {})
+        app.config.setdefault('FLASK_LOGGING_EXTRAS_BLUEPRINT',
+                              (None, '<app>', '<not a request>'))
 
         for kw in app.config['FLASK_LOGGING_EXTRAS_KEYWORDS']:
-            if kw in ['exc_info', 'extra', 'stack_info']:
-                raise ValueError(
-                    '"{keyword}" member of FLASK_LOGGING_EXTRAS_KEYWORDS is '
-                    'reserved for internal use.')
+            self._check_reserved_word(kw)
+
+        self._check_reserved_word(
+            app.config['FLASK_LOGGING_EXTRAS_BLUEPRINT'][0])
 
         self._valid_keywords = app.config['FLASK_LOGGING_EXTRAS_KEYWORDS']
+        (
+            self._blueprint_var,
+            self._blueprint_app,
+            self._blueprint_norequest,
+        ) = app.config['FLASK_LOGGING_EXTRAS_BLUEPRINT']
 
 
 def register_logger_class(cls=FlaskExtraLogger):

setup.py

@@ -8,7 +8,7 @@ Flask-Logging-Extras provides extra logging functionality for Flask apps.
 from setuptools import setup
 
 setup(name='Flask-Logging-Extras',
-      version='0.0.1',
+      version='0.1.0',
       url='https://github.com/gergelypolonkai/flask-logging-extras',
       license='MIT',
       author='Gergely Polonkai',

tests/test_logger_keywords.py

@@ -7,7 +7,7 @@ import logging
 import sys
 from unittest import TestCase
 
-from flask import Flask
+from flask import Flask, Blueprint, current_app
 
 import flask_logging_extras
 
@@ -173,3 +173,59 @@ class LoggerKeywordsTestCase(TestCase):
         # string "<unset>" will be assigned.
         app.logger.info('message')
         self.assertEqual('message [<unset>]\n', log_stream.lines[-1])
+
+
+class LoggerBlueprintTestCase(TestCase):
+    def setUp(self):
+        # Register our logger class
+        self.original_logger_class = logging.getLoggerClass()
+        flask_logging_extras.register_logger_class()
+
+        app = Flask('test_app')
+        self.app = app
+        app.config['FLASK_LOGGING_EXTRAS_BLUEPRINT'] = (
+            'bp', '<app>', '<norequest>')
+        app.logger.init_app(app)
+
+        fmt = '%(bp)s %(message)s'
+        self.stream = ListStream()
+
+        formatter = logging.Formatter(fmt)
+        handler = TestingStreamHandler(stream=self.stream)
+        handler.setLevel(logging.DEBUG)
+        handler.setFormatter(formatter)
+        app.logger.addHandler(handler)
+        app.logger.setLevel(logging.DEBUG)
+
+        bp = Blueprint('test_blueprint', 'test_bpg13')
+
+        @app.route('/app')
+        def route_1():
+            current_app.logger.info('Message')
+
+            return ''
+
+        @bp.route('/blueprint')
+        def route_2():
+            current_app.logger.info('Message')
+
+            return ''
+
+        app.register_blueprint(bp)
+
+        self.client = app.test_client()
+
+    def tearDown(self):
+        logging.setLoggerClass(self.original_logger_class)
+
+    def test_request_log(self):
+        self.client.get('/app')
+        self.assertEqual('<app> Message\n', self.stream.lines[-1])
+
+        page = self.client.get('/blueprint')
+        self.assertEqual('test_blueprint Message\n', self.stream.lines[-1])
+
+        with self.app.app_context():
+            current_app.logger.info('Message')
+
+        self.assertEqual('<norequest> Message\n', self.stream.lines[-1])