PyLogBeat

PyLogBeat is a simple, incomplete implementation of the Beats protocol used by Elastic Beats and Logstash. For more information about Beats see https://www.elastic.co/products/beats and https://www.elastic.co/guide/en/logstash/current/plugins-inputs-beats.html.

With this library it is possible to send log messages or any data to Logstash' beats input plugin or any other service which implements the Beats protocol.

The main difference to other transport mechanisms like direct TCP or UDP transfer is that with the Beats protocol there is a higher reliability of the data transfer, especially since the server acknowledges the data it received so the client knows whether and what to resend.

Installation

The easiest method is to install directly from pypi using pip:

pip install pylogbeat

If you prefer, you can download PyLogBeat from https://github.com/eht16/pylogbeat and install it directly from source:

python setup.py install

Due to a bug (logstash-plugins/logstash-input-beats#342) in some Logstash versions, you will need Logstash >= 5.6.12 or Logstash >= 6.4.0.

Get the Source

The source code is available at https://github.com/eht16/pylogbeat/.

Usage

Simple use

    message = {'@timestamp': '2018-01-02T01:02:03',  '@version': '1', 'message': 'hello world'}
    client = PyLogBeatClient('localhost', 5959, ssl_enable=False)
    client.connect()
    client.send([message])
    client.close()

Using a context manager

    with PyLogBeatClient('localhost', 5959, ssl_enable=False) as client:
        client.send([message])

Using a SSL connection

    with PyLogBeatClient('localhost', 5959, ssl_enable=True, ssl_verify=True,
            keyfile='certificate.key', certfile='certificate.crt', ca_certs='ca.crt') as client:
        client.send([message])

For details regarding the SSL certificates and how to configure the Logstash input for SSL, see https://www.elastic.co/guide/en/logstash/current/plugins-inputs-beats.html.

Message Format

PyLogBeatClient.send() accepts a sequence (list, tuple, set) of "messages". The messages itself can either be a dict object representing the final message to be sent to Logstash or a bytes or string object which must contain properly formatted JSON. If a dict is passed as element, it is converted to JSON using json.dumps().

Example message

The following example is a message as JSON:

    {
        "@timestamp": "2018-01-02T01:02:03",
        "@version": "1",
        "extra": {
            "application": "django_example",
            "django_version": "2.1.0",
            "environment": "production"
        },
        "host": "my-local-host",
        "level": "INFO",
        "logsource": "my-local-host",
        "message": "foo bar",
        "pid": 65534,
        "program": "example.py",
        "type": "python-logstash"
    }

This is the standard Logstash message format in JSON.

Logging

PyLogBeat uses a logger named "pylogbeat" to log some debug messages and warnings in case of errors. By default, the logger's log level is set to Warning so you will not see any debug log messages. If necessary simply change the log level of the logger to see the debug messages. For example:

    import logging
    logging.getLogger('pylogbeat').setLevel(logging.DEBUG)

It is important to make this change after you imported the pylogbeat module.

Furthermore, PyLogBeatClient's constructor method takes a use_logging argument which should be a boolean indicating whether the logging subsystem should be used at all. The argument defaults to False, i.e. if you want any logging, you need to pass True. If PyLogBeat is used itself as part of the logging system (e.g. as the transport of a handler), it is important to not emit any new log messages once the logging subsystem has been shutdown or is in the process of shutting down. In this case, use_logging must be False in order to suppress generating log messages.

Protocol Support

The implemented Beats protocol is not yet officially specified and documented, unfortunately. Hopefully the Beats developers will provide a specification in the future. So far, sending the data and waiting for the ACK from the server is implemented. But there might some details from the protocol missing in the implementation.

Future Maintenance

If you are interested in the code, want to improve it and/or complete the protocol support, please feel free to send PRs. I would be happy if someone likes to continue developing this library and would also take full maintainership for future development and releases.

Contributing

Found a bug or got a feature request? Please report it at https://github.com/eht16/pylogbeat/issues.

Credits

This code is based on https://github.com/brxie/PyLumberjack and adopted to support version 2 of the protocol. Thanks to brxie for the initial code.

ChangeLog

2.0.1 / 2023-07-30

• Load certificate chain only if a certificate was specified

2.0.0 / 2020-10-04

• Remove "six" dependency
• Require Python >= 3.6

1.0.5 / 2020-10-04

• Set python_requires to Python >=2.7 or Python >= 3.6 for smooth upgrade to upcoming Python3 only. This way Python2 only users will stay at this release.

1.0.4 / 2020-05-06

• Validate input data and fix documentation about accepted values (#2)

1.0.3 / 2020-04-22

• Add note about required Logstash versions (#1)
• Improve unit tests

1.0.2 / 2018-12-31

• Add badges to README

1.0.1 / 2018-12-31

• Fix typo in setup.py
• Use distribution "trusty" for Travis builds

1.0.0 / 2018-12-31

• Initial release

License

PyLogBeat is licensed under the Apache License 2.0.

Author

Enrico Tröger enrico.troeger@uvena.de