ElasticECSHandler.py

Python Elasticsearch ECS Log handler

This library provides an Elasticsearch logging appender compatible with the python standard logging library. It follows the Elastic Common Schema (ECS) for the field names. To follow the ECS mapping, please use an index template. Look at ECS Github repository for already generated ECS mappings objects or in the mappings folder of this repository where you will find a mapping file with the fields used by this handler. This handler use some custom fields. They are referenced in the mapping file.

The code source is in github at https://github.com/IMInterne/python-elasticsearch-ecs-logger.

Installation

Install using pip:

pip install ElasticECSHandler

Requirements Python 2

This library requires the following dependencies

• elasticsearch
• requests
• enum34

Requirements Python 3

This library requires the following dependencies

• elasticsearch
• requests

Additional requirements for Kerberos support

Additionally, the package support optionally kerberos authentication by adding the following dependecy

• requests-kerberos

Warning

Unfortunately, we don't have the time to test kerberos authenticationon support. We let the code here because it is simple and it should work.

Additional requirements for AWS IAM user authentication (request signing)

Additionally, the package support optionally AWS IAM user authentication by adding the following dependecy

• requests-aws4auth

Warning

Unfortunately, we don't have the time to test AWS IAM user authentication support. We let the code here because it is simple and it should work.

Using the handler in your program

To initialise and create the handler, just add the handler to your logger as follow

from elasticecslogging.handlers import ElasticECSHandler
handler = ElasticECSHandler(hosts=[{'host': 'localhost', 'port': 9200}],
                           auth_type=ElasticECSHandler.AuthType.NO_AUTH,
                           es_index_name="my_python_index")
log = logging.getLogger("PythonTest")
log.setLevel(logging.INFO)
log.addHandler(handler)

You can add fields upon initialisation, providing more data of the execution context

from elasticecslogging.handlers import ElasticECSHandler
handler = ElasticECSHandler(hosts=[{'host': 'localhost', 'port': 9200}],
                           auth_type=ElasticECSHandler.AuthType.NO_AUTH,
                           es_index_name="my_python_index",
                           es_additional_fields={'App': 'MyAppName', 'Environment': 'Dev'})
log = logging.getLogger("PythonTest")
log.setLevel(logging.INFO)
log.addHandler(handler)

This additional fields will be applied to all logging fields and recorded in elasticsearch

To log, use the regular commands from the logging library

log.info("This is an info statement that will be logged into elasticsearch")

Your code can also dump additional extra fields on a per log basis that can be used to instrument operations. For example, when reading information from a database you could do something like:

start_time = time.time()
database_operation()
db_delta = time.time() - start_time
log.debug("DB operation took %.3f seconds" % db_delta, extra={'db_execution_time': db_delta})

The code above executes the DB operation, measures the time it took and logs an entry that contains in the message the time the operation took as string and for convenience, it creates another field called db_execution_time with a float that can be used to plot the time this operations are taking using Kibana on top of elasticsearch

Initialisation parameters

The constructors takes the following parameters:

• hosts: The list of hosts that elasticsearch clients will connect, multiple hosts are allowed, for example

  [{'host':'host1','port':9200}, {'host':'host2','port':9200}]
  

• auth_type: The authentication currently support ElasticECSHandler.AuthType = NO_AUTH, BASIC_AUTH, KERBEROS_AUTH

• auth_details: When ElasticECSHandler.AuthType.BASIC_AUTH is used this argument must contain a tuple of string with the user and password that will be used to authenticate against the Elasticsearch servers, for example ('User','Password')

• aws_access_key: When ElasticECSHandler.AuthType.AWS_SIGNED_AUTH is used this argument must contain the AWS key id of the the AWS IAM user

• aws_secret_key: When ElasticECSHandler.AuthType.AWS_SIGNED_AUTH is used this argument must contain the AWS secret key of the the AWS IAM user

• aws_region: When ElasticECSHandler.AuthType.AWS_SIGNED_AUTH is used this argument must contain the AWS region of the the AWS Elasticsearch servers, for example 'us-east'

• use_ssl: A boolean that defines if the communications should use SSL encrypted communication

• verify_ssl: A boolean that defines if the SSL certificates are validated or not

• buffer_size: An int, Once this size is reached on the internal buffer results are flushed into ES

• flush_frequency_in_sec: A float representing how often and when the buffer will be flushed

• es_index_name: A string with the prefix of the elasticsearch index that will be created. Note a date with YYYY.MM.dd, python_logger used by default

• index_name_frequency: The frequency to use as part of the index naming. Currently supports ElasticECSHandler.IndexNameFrequency.DAILY, ElasticECSHandler.IndexNameFrequency.WEEKLY, ElasticECSHandler.IndexNameFrequency.MONTHLY, ElasticECSHandler.IndexNameFrequency.YEARLY and ElasticECSHandler.IndexNameFrequency.NEVER. By default the daily rotation is used.

• es_additional_fields: A nested dictionary with all the additional fields that you would like to add to the logs.

• es_additional_fields_in_env: A nested dictionary with all the additional fields that you would like to add to the logs. The values are environment variables keys. At each elastic document created, the values of these environment variables will be read. If an environment variable for a field doesn't exists, the value of the same field in es_additional_fields will be taken if it exists. In last resort, there will be no value for the field.

Django Integration

It is also very easy to integrate the handler to Django And what is even better, at DEBUG level django logs information such as how long it takes for DB connections to return so they can be plotted on Kibana, or the SQL statements that Django executed.

from elasticecslogging.handlers import ElasticECSHandler
LOGGING = {
    'version': 1,
    'disable_existing_loggers': False,
    'handlers': {
        'file': {
            'level': 'DEBUG',
            'class': 'logging.handlers.RotatingFileHandler',
            'filename': './debug.log',
            'maxBytes': 102400,
            'backupCount': 5,
        },
        'elasticsearch': {
            'level': 'DEBUG',
            'class': 'elasticecslogging.handlers.ElasticECSHandler',
            'hosts': [{'host': 'localhost', 'port': 9200}],
            'es_index_name': 'my_python_app',
            'es_additional_fields': {'App': 'Test', 'Environment': 'Dev'},
            'auth_type': ElasticECSHandler.AuthType.NO_AUTH,
            'use_ssl': False,
        },
    },
    'loggers': {
        'django': {
            'handlers': ['file','elasticsearch'],
            'level': 'DEBUG',
            'propagate': True,
        },
    },
}

There is more information about how Django logging works in the Django documentation

Building the sources & Testing

To create the package follow the standard python setup.py to compile. To test, just execute the python tests within the test folder

Why using an appender rather than logstash or beats

In some cases is quite useful to provide all the information available within the LogRecords as it contains things such as exception information, the method, file, log line where the log was generated.

If you are interested on understanding more about the differences between the agent vs handler approach, I'd suggest reading this conversation thread

The same functionality can be implemented in many other different ways. For example, consider the integration using SysLogHandler and logstash syslog plugin.

Contributing back

Feel free to use this as is or even better, feel free to fork and send your pull requests over.