Metadata-Version: 1.2
Name: fluent-logger
Version: 0.9.6
Summary: A Python logging handler for Fluentd event collector
Home-page: https://github.com/fluent/fluent-logger-python
Author: Kazuki Ohta
Author-email: kazuki.ohta@gmail.com
License: Apache License, Version 2.0
Download-URL: http://pypi.python.org/pypi/fluent-logger/
Description: A Python structured logger for Fluentd
        ======================================
        
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           :alt: Build Status
        
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        Many web/mobile applications generate huge amount of event logs (c,f.
        login, logout, purchase, follow, etc). To analyze these event logs could
        be really valuable for improving the service. However, the challenge is
        collecting these logs easily and reliably.
        
        `Fluentd <https://github.com/fluent/fluentd>`__ solves that problem by
        having: easy installation, small footprint, plugins, reliable buffering,
        log forwarding, etc.
        
        **fluent-logger-python** is a Python library, to record the events from
        Python application.
        
        Requirements
        ------------
        
        -  Python 2.7 or 3.4+
        - ``msgpack-python``
        - **IMPORTANT**: Version 0.8.0 is the last version supporting Python 2.6, 3.2 and 3.3
        
        Installation
        ------------
        
        This library is distributed as 'fluent-logger' python package. Please
        execute the following command to install it.
        
        .. code:: sh
        
            $ pip install fluent-logger
        
        Configuration
        -------------
        
        Fluentd daemon must be launched with a tcp source configuration:
        
        ::
        
            <source>
              type forward
              port 24224
            </source>
        
        To quickly test your setup, add a matcher that logs to the stdout:
        
        ::
        
            <match app.**>
              type stdout
            </match>
        
        Usage
        -----
        
        FluentSender Interface
        ~~~~~~~~~~~~~~~~~~~~~~
        
        `sender.FluentSender` is a structured event logger for Fluentd.
        
        By default, the logger assumes fluentd daemon is launched locally. You
        can also specify remote logger by passing the options.
        
        .. code:: python
        
            from fluent import sender
        
            # for local fluent
            logger = sender.FluentSender('app')
        
            # for remote fluent
            logger = sender.FluentSender('app', host='host', port=24224)
        
        For sending event, call `emit` method with your event. Following example will send the event to
        fluentd, with tag 'app.follow' and the attributes 'from' and 'to'.
        
        .. code:: python
        
            # Use current time
            logger.emit('follow', {'from': 'userA', 'to': 'userB'})
        
            # Specify optional time
            cur_time = int(time.time())
            logger.emit_with_time('follow', cur_time, {'from': 'userA', 'to':'userB'})
        
        To send events with nanosecond-precision timestamps (Fluent 0.14 and up),
        specify `nanosecond_precision` on `FluentSender`.
        
        .. code:: python
        
            # Use nanosecond
            logger = sender.FluentSender('app', nanosecond_precision=True)
            logger.emit('follow', {'from': 'userA', 'to': 'userB'})
            logger.emit_with_time('follow', time.time(), {'from': 'userA', 'to': 'userB'})
        
        You can detect an error via return value of `emit`. If an error happens in `emit`, `emit` returns `False` and get an error object using `last_error` method.
        
        .. code:: python
        
            if not logger.emit('follow', {'from': 'userA', 'to': 'userB'}):
                print(logger.last_error)
                logger.clear_last_error() # clear stored error after handled errors
        
        If you want to shutdown the client, call `close()` method.
        
        .. code:: python
        
            logger.close()
        
        Event-Based Interface
        ~~~~~~~~~~~~~~~~~~~~~
        
        This API is a wrapper for `sender.FluentSender`.
        
        First, you need to call ``sender.setup()`` to create global `sender.FluentSender` logger
        instance. This call needs to be called only once, at the beginning of
        the application for example.
        
        Initialization code of Event-Based API is below:
        
        .. code:: python
        
            from fluent import sender
        
            # for local fluent
            sender.setup('app')
        
            # for remote fluent
            sender.setup('app', host='host', port=24224)
        
        Then, please create the events like this. This will send the event to
        fluentd, with tag 'app.follow' and the attributes 'from' and 'to'.
        
        .. code:: python
        
            from fluent import event
        
            # send event to fluentd, with 'app.follow' tag
            event.Event('follow', {
              'from': 'userA',
              'to':   'userB'
            })
        
        `event.Event` has one limitation which can't return success/failure result.
        
        Other methods for Event-Based Interface.
        
        .. code:: python
        
            sender.get_global_sender # get instance of global sender
            sender.close # Call FluentSender#close
        
        Handler for buffer overflow
        ~~~~~~~~~~~~~~~~~~~~~~~~~~~
        
        You can inject your own custom proc to handle buffer overflow in the event of connection failure. This will mitigate the loss of data instead of simply throwing data away.
        
        .. code:: python
        
            import msgpack
            from io import BytesIO
        
            def overflow_handler(pendings):
                unpacker = msgpack.Unpacker(BytesIO(pendings))
                for unpacked in unpacker:
                    print(unpacked)
        
            logger = sender.FluentSender('app', host='host', port=24224, buffer_overflow_handler=overflow_handler)
        
        You should handle any exception in handler. fluent-logger ignores exceptions from ``buffer_overflow_handler``.
        
        This handler is also called when pending events exist during `close()`.
        
        Python logging.Handler interface
        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
        
        This client-library also has ``FluentHandler`` class for Python logging
        module.
        
        .. code:: python
        
            import logging
            from fluent import handler
        
            custom_format = {
              'host': '%(hostname)s',
              'where': '%(module)s.%(funcName)s',
              'type': '%(levelname)s',
              'stack_trace': '%(exc_text)s'
            }
        
            logging.basicConfig(level=logging.INFO)
            l = logging.getLogger('fluent.test')
            h = handler.FluentHandler('app.follow', host='host', port=24224, buffer_overflow_handler=overflow_handler)
            formatter = handler.FluentRecordFormatter(custom_format)
            h.setFormatter(formatter)
            l.addHandler(h)
            l.info({
              'from': 'userA',
              'to': 'userB'
            })
            l.info('{"from": "userC", "to": "userD"}')
            l.info("This log entry will be logged with the additional key: 'message'.")
        
        You can also customize formatter via logging.config.dictConfig
        
        .. code:: python
        
            import logging.config
            import yaml
        
            with open('logging.yaml') as fd:
                conf = yaml.load(fd)
        
            logging.config.dictConfig(conf['logging'])
        
        You can inject your own custom proc to handle buffer overflow in the event of connection failure. This will mitigate the loss of data instead of simply throwing data away.
        
        .. code:: python
        
            import msgpack
            from io import BytesIO
        
            def overflow_handler(pendings):
                unpacker = msgpack.Unpacker(BytesIO(pendings))
                for unpacked in unpacker:
                    print(unpacked)
        
        A sample configuration ``logging.yaml`` would be:
        
        .. code:: python
        
            logging:
                version: 1
        
                formatters:
                  brief:
                    format: '%(message)s'
                  default:
                    format: '%(asctime)s %(levelname)-8s %(name)-15s %(message)s'
                    datefmt: '%Y-%m-%d %H:%M:%S'
                  fluent_fmt:
                    '()': fluent.handler.FluentRecordFormatter
                    format:
                      level: '%(levelname)s'
                      hostname: '%(hostname)s'
                      where: '%(module)s.%(funcName)s'
        
                handlers:
                    console:
                        class : logging.StreamHandler
                        level: DEBUG
                        formatter: default
                        stream: ext://sys.stdout
                    fluent:
                        class: fluent.handler.FluentHandler
                        host: localhost
                        port: 24224
                        tag: test.logging
                        buffer_overflow_handler: overflow_handler
                        formatter: fluent_fmt
                        level: DEBUG
                    none:
                        class: logging.NullHandler
        
                loggers:
                    amqp:
                        handlers: [none]
                        propagate: False
                    conf:
                        handlers: [none]
                        propagate: False
                    '': # root logger
                        handlers: [console, fluent]
                        level: DEBUG
                        propagate: False
        
        Asynchronous Communication
        ~~~~~~~~~~~~~~~~~~~~~~~~~~
        
        Besides the regular interfaces - the event-based one provided by ``sender.FluentSender`` and the python logging one
        provided by ``handler.FluentHandler`` - there are also corresponding asynchronous versions in ``asyncsender`` and
        ``asynchandler`` respectively. These versions use a separate thread to handle the communication with the remote fluentd
        server. In this way the client of the library won't be blocked during the logging of the events, and won't risk going
        into timeout if the fluentd server becomes unreachable. Also it won't be slowed down by the network overhead.
        
        The interfaces in ``asyncsender`` and ``asynchandler`` are exactly the same as those in ``sender`` and ``handler``, so it's
        just a matter of importing from a different module.
        
        For instance, for the event-based interface:
        
        .. code:: python
        
            from fluent import asyncsender as sender
        
            # for local fluent
            sender.setup('app')
        
            # for remote fluent
            sender.setup('app', host='host', port=24224)
        
            # do your work
            ...
        
            # IMPORTANT: before program termination, close the sender
            sender.close()
        
        or for the python logging interface:
        
        .. code:: python
        
            import logging
            from fluent import asynchandler as handler
        
            custom_format = {
              'host': '%(hostname)s',
              'where': '%(module)s.%(funcName)s',
              'type': '%(levelname)s',
              'stack_trace': '%(exc_text)s'
            }
        
            logging.basicConfig(level=logging.INFO)
            l = logging.getLogger('fluent.test')
            h = handler.FluentHandler('app.follow', host='host', port=24224, buffer_overflow_handler=overflow_handler)
            formatter = handler.FluentRecordFormatter(custom_format)
            h.setFormatter(formatter)
            l.addHandler(h)
            l.info({
              'from': 'userA',
              'to': 'userB'
            })
            l.info('{"from": "userC", "to": "userD"}')
            l.info("This log entry will be logged with the additional key: 'message'.")
        
            ...
        
            # IMPORTANT: before program termination, close the handler
            h.close()
        
        **NOTE**: please note that it's important to close the sender or the handler at program termination. This will make
        sure the communication thread terminates and it's joined correctly. Otherwise the program won't exit, waiting for
        the thread, unless forcibly killed.
        
        Circular queue mode
        +++++++++++++++++++
        
        In some applications it can be especially important to guarantee that the logging process won't block under *any*
        circumstance, even when it's logging faster than the sending thread could handle (*backpressure*). In this case it's
        possible to enable the `circular queue` mode, by passing `True` in the `queue_circular` parameter of
        ``asyncsender.FluentSender`` or ``asynchandler.FluentHandler``. By doing so the thread doing the logging won't block
        even when the queue is full, the new event will be added to the queue by discarding the oldest one.
        
        **WARNING**: setting `queue_circular` to `True` will cause loss of events if the queue fills up completely! Make sure
        that this doesn't happen, or it's acceptable for your application.
        
        
        Testing
        -------
        
        Testing can be done using
        `nose <https://nose.readthedocs.org/en/latest/>`__.
        
        Release
        -------
        
        Need wheel package.
        
        .. code:: sh
        
            $ pip install wheel
        
        After that, type following command:
        
        .. code:: sh
        
            $ python setup.py clean sdist bdist_wheel upload
        
        Contributors
        ------------
        
        Patches contributed by `those
        people <https://github.com/fluent/fluent-logger-python/contributors>`__.
        
        License
        -------
        
        Apache License, Version 2.0
        
Platform: UNKNOWN
Classifier: Programming Language :: Python :: 2
Classifier: Programming Language :: Python :: 2.7
Classifier: Programming Language :: Python :: 3
Classifier: Programming Language :: Python :: 3.4
Classifier: Programming Language :: Python :: 3.5
Classifier: Programming Language :: Python :: 3.6
Classifier: Programming Language :: Python :: 3.7
Classifier: Programming Language :: Python :: Implementation :: CPython
Classifier: Programming Language :: Python :: Implementation :: PyPy
Classifier: Development Status :: 5 - Production/Stable
Classifier: Topic :: System :: Logging
Classifier: Intended Audience :: Developers
Requires-Python: >=2.7,!=3.0,!=3.1,!=3.2,!=3.3
