Flask-Logging-Extras

Flask-Logging-Extras adds additional logging features for Flask applications.

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:

fmt = '[%(asctime)s] [%(levelname)s] [%(category)s] %(message'
# Initialize log handlers as usual, like creating a FileHandler, and
# assign fmt to it as a format string
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.

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

The easiest way to start using the package is with pip:

$ pip install Flask-Logging-Extras

If you prefer to install from source, you can clone this repo and run

$ python setup.py install

Usage

View the documentation online

Testing and Code Coverage

We require 100% code coverage in our unit tests. We run all the unit tests with tox, which will test against python2.7, 3.3, 3.4, and 3.5.

Running tox will print out a code coverage report. Coverage report is also available on codecov.

tox is running automatically for every push in Travis-CI. To run tox on your local machine, you can simply invoke it with the tox command.

Generating Documentation

You can generate a local copy of the documentation. First, make sure you have the flask sphinx theme available. You can get it (and all possible documentation requirements) with

$ pip install -r docs-requirements.txt

Then in the docs/ directory, run

$ make clean && make html

License

This module is available under the MIT license.