Metadata-Version: 2.1 Name: aiologger Version: 0.6.0 Summary: Asynchronous logging for python and asyncio Home-page: https://github.com/b2wdigital/aiologger Author: Diogo Magalhães Martins Author-email: magalhaesmartins@icloud.com License: MIT Project-URL: Documentation, https://aiologger.readthedocs.io/en/latest/ Project-URL: Code, https://github.com/b2wdigital/aiologger Project-URL: Issue tracker, https://github.com/b2wdigital/aiologger/issues Description: # aiologger [![PYPI](https://img.shields.io/pypi/v/aiologger.svg)](http://pypi.python.org/pypi/aiologger) [![PYPI Python Versions](https://img.shields.io/pypi/pyversions/aiologger.svg)](http://pypi.python.org/pypi/aiologger) [![Build Status](https://travis-ci.org/B2W-BIT/aiologger.svg?branch=master)](https://travis-ci.org/B2W-BIT/aiologger) [![codecov](https://codecov.io/gh/B2W-BIT/aiologger/branch/master/graph/badge.svg)](https://codecov.io/gh/B2W-BIT/aiologger) # About the Project The builtin python logger is I/O blocking. This means that using the builtin `logging` module will interfere with your asynchronouns application performance. `aiologger` aims to be the standard Asynchronous non blocking logging for python and asyncio. # A word about async, Python and files Tldr; `aiologger` is only fully async when logging to stdout/stderr. If you log into files on disk you are not being fully async and will be using Threads. `aiologger` was created when we realized that there were no async logging libs to use. At the time, Python's built-in logging infra-structure was fully sync (still is, 3.8 beta is out). That's why we created aiologger. Despite everything (in Linux) being a file descriptor, a Network file descriptor and the stdout/stderr FDs are treated differently from files on disk FDs. This happens because there's no stable/usable async I/O interface published by the OS to be used by Python (or any other language). That's why **logging to files is NOT truly async**. `aiologger` implementation of file logging uses [aiofiles](https://github.com/Tinche/aiofiles), which uses a Thread Pool to write the data. Keep this in mind when using `aiologger` for file logging. Other than that, we hope `aiologger` helps you write fully async apps. :tada: :tada: # Installation ``` pip install aiologger ``` # Testing ``` pipenv install --dev pipenv run test ``` # Implemented interfaces aiologger implements two different interfaces that you can use to generate your logs. You can generate your logs using the `async/await` syntax or, if you for any reason can't (or don't want to) change all your codebase to use this syntax you can use aiologger as if it were synchronous, but behind the scenes your logs will be generated asynchronously. # Migrating from standard lib logging ## Using aiologger with the standard syntax If you prefer not to use the `async/await` all you need to do is to replace you logger instance with an instance of `aiologger.Logger`. For now on you can call `logger.info()` the same way you are (probably) already calling. Here is a simple example: ```python import asyncio import logging from logging import getLogger async def main(): logger = getLogger(__name__) logging.basicConfig(level=logging.DEBUG, format="%(message)s") logger.debug("debug") logger.info("info") logger.warning("warning") logger.error("error") logger.critical("critical") if __name__ == "__main__": asyncio.run(main()) ``` Which will output the following lines: ``` debug info warning error critical ``` --- If you want to generate all your logs asynchronously, you just have to change the instance of the `logger` object. To do that, all we need to change those lines from: ```python from logging import getLogger logger = getLogger(__name__) ``` to: ```python from aiologger import Logger logger = Logger.with_default_handlers() ``` and here is the complete example, generating all log lines asynchronously. ```python import asyncio from aiologger import Logger async def main(): logger = Logger.with_default_handlers(name='my-logger') logger.debug("debug") logger.info("info") logger.warning("warning") logger.error("error") logger.critical("critical") await logger.shutdown() if __name__ == "__main__": asyncio.run(main()) ``` This code will output the following lines: ``` warning debug info error critical ``` As you might have noticed, the output order **IS NOT GUARANTEED**. If some kind of order is important to you, you'll need to use the `await` syntax. But thinking about an asyncio application, where every I/O operation is asynchronous, this shouldn't really matter. Also note that logger calls may only be made from an `async def` or from a function called with an `async def` somewhere in the callstack. ## Using aiologger with the async/await syntax ```python import asyncio from aiologger import Logger async def main(): logger = Logger.with_default_handlers(name='my-logger') await logger.debug("debug at stdout") await logger.info("info at stdout") await logger.warning("warning at stderr") await logger.error("error at stderr") await logger.critical("critical at stderr") await logger.shutdown() if __name__ == "__main__": asyncio.run(main()) ``` The most basic use case is to log the output into `stdout` and `stderr`. Using `Logger.with_default_handlers` you're able to effortlessly create a new `Logger` instance with 2 distinct handlers: * One for handling `debug` and `info` methods and writing to `stdout`; * The other, for handling `warning`, `critical`, `exception` and `error` methods and writing to `stderr`. Since everything is asynchronous, this means that for the same handler, the output order is guaranteed, but not between distinct handlers. The above code may output the following: ``` warning at stderr debug at stdout error at stderr info at stdout critical at stderr ``` You may notice that the order between the same handler is guaranteed. E.g.: * `debug at stdout` was outputted before `info at stdout` * `warning at stderr` was outputted before `error at stderr` * between lines of distinct handlers, the order isn't guaranteed. `warning at stderr` was outputted before `debug at stdout` ## Lazy initialization Since the actual stream initialization only happens on the first log call, it's possible to initialize `aiologger.Logger` instances outside a running event loop: ```python import asyncio from aiologger import Logger logger = Logger.with_default_handlers(name='my-logger') async def main(): await logger.debug("debug at stdout") await logger.info("info at stdout") await logger.warning("warning at stderr") await logger.error("error at stderr") await logger.critical("critical at stderr") await logger.shutdown() if __name__ == "__main__": asyncio.run(main()) ``` # Loggers ## JsonLogger A simple, featureful, drop-in replacement to the default `aiologger.Logger` that grants to always log valid, single line, JSON output. ### It logs everything ```python import asyncio from datetime import datetime from aiologger.loggers.json import JsonLogger async def main(): logger = JsonLogger.with_default_handlers() await logger.info("Im a string") # {"logged_at": "2018-06-14T09:34:56.482817", "line_number": 9, "function": "main", "level": "INFO", "file_path": "/Users/diogo.mmartins/Library/Preferences/PyCharm2018.1/scratches/scratch_47.py", "msg": "Im a string"} await logger.info({ 'date_objects': datetime.now(), 'exceptions': KeyError("Boooom"), 'types': JsonLogger }) # {"logged_at": "2018-06-14T09:34:56.483000", "line_number": 13, "function": "main", "level": "INFO", "file_path": "/Users/diogo.mmartins/Library/Preferences/PyCharm2018.1/scratches/scratch_47.py", "msg": {"date_objects": "2018-06-14T09:34:56.482953", "exceptions": "Exception: KeyError('Boooom',)", "types": ""}} await logger.shutdown() if __name__ == "__main__": asyncio.run(main()) ``` ### JsonLogger Options `Callable[[], str]` log values may also be used to generate dynamic content that are evaluated at serialization time. All you need to do is wrap the callable using `CallableWrapper`: ```python import asyncio import logging from random import randint from aiologger.loggers.json import JsonLogger from aiologger.utils import CallableWrapper def rand(): return randint(1, 100) logger = JsonLogger.with_default_handlers(level=logging.DEBUG) async def main(): await logger.info(CallableWrapper(rand)) # {"logged_at": "2018-06-14T09:37:52.624123", "line_number": 15, "function": "main", "level": "INFO", "file_path": "/Users/diogo.mmartins/Library/Preferences/PyCharm2018.1/scratches/scratch_47.py", "msg": 70} await logger.info({"Xablau": CallableWrapper(rand)}) # {"logged_at": "2018-06-14T09:37:52.624305", "line_number": 18, "function": "main", "level": "INFO", "file_path": "/Users/diogo.mmartins/Library/Preferences/PyCharm2018.1/scratches/scratch_47.py", "msg": {"Xablau": 29}} await logger.shutdown() if __name__ == "__main__": asyncio.run(main()) ``` ### Adding content to root By default, everything passed to the log methods is inserted inside the `msg` root attribute, but sometimes we want to add content to the root level. #### Flatten This behavior may be achieved using `flatten`. Which is available both as a method parameter and instance attribute. As an instance attribute, every call to a log method would "flat" the dict attributes. ```python import asyncio import logging from aiologger.loggers.json import JsonLogger async def main(): logger = JsonLogger.with_default_handlers(level=logging.DEBUG, flatten=True) await logger.info({"status_code": 200, "response_time": 0.00534534}) # {"status_code": 200, "response_time": 0.534534, "logged_at": "2017-08-11T16:18:58.446985", "line_number": 6, "function": "", "level": "INFO", "path": "/Users/diogo/PycharmProjects/aiologger/bla.py"} await logger.error({"status_code": 404, "response_time": 0.00134534}) # {"status_code": 200, "response_time": 0.534534, "logged_at": "2017-08-11T16:18:58.446986", "line_number": 6, "function": "", "level": "INFO", "path": "/Users/diogo/PycharmProjects/aiologger/bla.py"} await logger.shutdown() if __name__ == "__main__": asyncio.run(main()) ``` As a method parameter, only the specific call would add the content to the root. ```python import asyncio import logging from aiologger.loggers.json import JsonLogger async def main(): logger = await JsonLogger.with_default_handlers(level=logging.DEBUG) await logger.info({"status_code": 200, "response_time": 0.00534534}, flatten=True) # {"logged_at": "2017-08-11T16:23:16.312441", "line_number": 6, "function": "", "level": "INFO", "path": "/Users/diogo/PycharmProjects/aiologger/bla.py", "status_code": 200, "response_time": 0.00534534} await logger.error({"status_code": 404, "response_time": 0.00134534}) # {"logged_at": "2017-08-11T16:23:16.312618", "line_number": 8, "function": "", "level": "ERROR", "path": "/Users/diogo/PycharmProjects/aiologger/bla.py", "msg": {"status_code": 404, "response_time": 0.00134534}} await logger.shutdown() if __name__ == "__main__": asyncio.run(main()) ``` **Warning**: It is possible to overwrite keys that are already present at root level. ```python import asyncio import logging from aiologger.loggers.json import JsonLogger async def main(): logger = JsonLogger.with_default_handlers(level=logging.DEBUG) await logger.info({'logged_at': 'Yesterday'}, flatten=True) # {"logged_at": "Yesterday", "line_number": 6, "function": "", "level": "INFO", "path": "/Users/diogo/PycharmProjects/aiologger/bla.py"} await logger.shutdown() if __name__ == "__main__": asyncio.run(main()) ``` #### Extra The `extra` parameter allow you to add specific content to root: ```python import asyncio import logging from aiologger.loggers.json import JsonLogger async def main(): a = 69 b = 666 c = [a, b] logger = JsonLogger.with_default_handlers(level=logging.DEBUG) await logger.info("I'm a simple log") # {"msg": "I'm a simple log", "logged_at": "2017-08-11T12:21:05.722216", "line_number": 5, "function": "", "level": "INFO", "path": "/Users/diogo/PycharmProjects/aiologger/bla.py"} await logger.info({"dog": "Xablau"}, extra=locals()) # {"logged_at": "2018-06-14T09:47:29.477705", "line_number": 14, "function": "main", "level": "INFO", "file_path": "/Users/diogo.mmartins/Library/Preferences/PyCharm2018.1/scratches/scratch_47.py", "msg": {"dog": "Xablau"}, "logger": "", "c": [69, 666], "b": 666, "a": 69} await logger.shutdown() if __name__ == "__main__": asyncio.run(main()) ``` It also allows you to override the default root content: ```python import asyncio import logging from aiologger.loggers.json import JsonLogger async def main(): logger = JsonLogger.with_default_handlers(level=logging.DEBUG) await logger.info("I'm a simple log") # {"msg": "I'm a simple log", "logged_at": "2017-08-11T12:21:05.722216", "line_number": 6, "function": "", "level": "INFO", "path": "/Users/diogo/PycharmProjects/aiologger/bla.py"} await logger.info("I'm a simple log", extra={'logged_at': 'Yesterday'}) # {"msg": "I'm a simple log", "logged_at": "Yesterday", "line_number": 6, "function": "", "level": "INFO", "path": "/Users/diogo/PycharmProjects/aiologger/bla.py"} await logger.shutdown() if __name__ == "__main__": asyncio.run(main()) ``` and it may also be used as an instance attribute: ```python import asyncio import logging from aiologger.loggers.json import JsonLogger async def main(): logger = JsonLogger.with_default_handlers(level=logging.DEBUG, extra={'logged_at': 'Yesterday'}) await logger.info("I'm a simple log") # {"msg": "I'm a simple log", "logged_at": "Yesterday", "line_number": 6, "function": "", "level": "INFO", "path": "/Users/diogo/PycharmProjects/aiologger/bla.py"} await logger.info("I'm a simple log") # {"msg": "I'm a simple log", "logged_at": "Yesterday", "line_number": 6, "function": "", "level": "INFO", "path": "/Users/diogo/PycharmProjects/aiologger/bla.py"} await logger.shutdown() if __name__ == "__main__": asyncio.run(main()) ``` #### Exclude default logger fields If you think that the default fields are too much, it's also possible to exclude fields from the output message. ```python import asyncio import logging from aiologger.loggers.json import JsonLogger from aiologger.formatters.json import FUNCTION_NAME_FIELDNAME, LOGGED_AT_FIELDNAME async def main(): logger = JsonLogger.with_default_handlers( level=logging.DEBUG, exclude_fields=[FUNCTION_NAME_FIELDNAME, LOGGED_AT_FIELDNAME, 'file_path', 'line_number'] ) await logger.info("Function, file path and line number wont be printed") # {"level": "INFO", "msg": "Function, file path and line number wont be printed"} await logger.shutdown() if __name__ == "__main__": asyncio.run(main()) ``` ### Serializer options `serializer_kwargs` is available both as instance attribute and as a log method parameter and may be used to pass keyword arguments to the `serializer` function. (See more: https://docs.python.org/3/library/json.html) For pretty printing the output, you may use the `indent` kwarg. Ex.: ```python import asyncio import logging from aiologger.loggers.json import JsonLogger async def main(): logger = JsonLogger.with_default_handlers( level=logging.DEBUG, serializer_kwargs={'indent': 4} ) await logger.info({ "artist": "Black Country Communion", "song": "Cold" }) await logger.shutdown() if __name__ == "__main__": asyncio.run(main()) ``` Would result in a pretty indented output: ```javascript { "logged_at": "2017-08-11T21:04:21.559070", "line_number": 5, "function": "", "level": "INFO", "file_path": "/Users/diogo/Library/Preferences/PyCharm2017.1/scratches/scratch_32.py", "msg": { "artist": "Black Country Communion", "song": "Cold" } } ``` The same result can be achieved making a log call with `serializer_kwargs` as a parameter. ```python await logger.warning({'artist': 'Black Country Communion', 'song': 'Cold'}, serializer_kwargs={'indent': 4}) ``` # Handlers ## AsyncStreamHandler A handler class for writing logs into a stream which may be `sys.stdout` or `sys.stderr`. If a stream isn't provided, it defaults to `sys.stderr`. If `level` is not specified, `logging.NOTSET` is used. If `formatter` is not `None`, it is used to format the log record before `emit()` gets called. A `filter` may be used to filter log records ```python import sys from aiologger.handlers.streams import AsyncStreamHandler handler = AsyncStreamHandler(stream=sys.stdout) ``` It also accepts a level, formatter and filter at the initialization. ## AsyncFileHandler **Important**: AsyncFileHandler depends on a optional dependency and you should install aiologger with `pip install aiologger[aiofiles]` A handler class that sends logs into files. The specified file is opened and used as the _stream_ for logging. If `mode` is not specified, 'a' is used. If `encoding` is not `None`, it is used to open the file with that encoding. The file opening is delayed until the first call to `emit()`. ```python from aiologger.handlers.files import AsyncFileHandler from tempfile import NamedTemporaryFile temp_file = NamedTemporaryFile() handler = AsyncFileHandler(filename=temp_file.name) ``` # Options * `AIOLOGGER_HANDLE_ERROR_FALLBACK_ENABLED` - An environment variable that tells aiologger whether it should emit a log to `stderr` in case of a handler emit raises an exceptions. To disable the default behaviour, set this environment variable to a falsy value `("False", "false", "0")`. Default: `True` # Compatibility The explicit passing of a `loop` keyword argument, and subsequent access of a `.loop` attribute, has been deprecated and will be removed in version 0.7.0 for Loggers and Handlers. Currently tested only on python 3.6 and 3.7 # Depencencies Has none. Keywords: logging json log output Platform: UNKNOWN Classifier: Development Status :: 4 - Beta Classifier: Framework :: AsyncIO Classifier: Intended Audience :: Developers Classifier: License :: OSI Approved :: MIT License Classifier: Intended Audience :: System Administrators Classifier: Intended Audience :: Information Technology Classifier: Natural Language :: English Classifier: Operating System :: MacOS :: MacOS X Classifier: Operating System :: Unix Classifier: Programming Language :: Python :: 3.6 Classifier: Programming Language :: Python :: 3.7 Classifier: Topic :: System :: Logging Classifier: Topic :: Software Development :: Libraries Requires-Python: >=3.6 Description-Content-Type: text/markdown Provides-Extra: aiofiles