How to get started quickly using the Logging module in Python

Configure Logging module

Logging module provides basic configuration through the logging.basicConfig() function. You can use this function to set the Log logging level (such as INFO or DEBUG), handler (such as console or file), and formatter (used to customize the appearance of log messages). The following is an example configuration:

import logging

logging.basicConfig(level=logging.INFO,
fORMat="%(asctime)s - %(levelname)s - %(message)s",
datefmt="%Y-%m-%d %H:%M:%S")

Add logger

To start logging, you need to create a logger. Get a logger using the logging.getLogger() function, which will retrieve or create a logger from the root logger based on the name provided.

logger = logging.getLogger(__name__)

Record message

Use debug(), info(), warning(), error() and # from the logger ##critical() Method records messages. These methods correspond to different logging levels.

logger.info("Application started")
logger.error("An error occurred")

Configure logging level

The logging level controls the types of messages that need to be logged. You can set the logging level using the

logging.setLevel() function. Levels are sorted from lowest to highest, DEBUG, INFO, WARNING, ERROR, and CRITICAL.

logger.setLevel(logging.DEBUG)

Use handlers

Handlers are used to send log messages to a specific destination, such as the console, a file, or a remote

server

. You can add a handler using the logging.addHandler() function. <pre class="brush:python;toolbar:false;">import logging.handlers # 将日志输出到控制台 console_handler = logging.StreamHandler() logger.addHandler(console_handler) # 将日志输出到文件 file_handler = logging.FileHandler(&quot;app.log&quot;) logger.addHandler(file_handler)</pre>

Use formatter

Formatters are used to customize the appearance of log messages. You can create a formatter using the

logging.Formatter()

function. FormatterStringUse the following placeholders:

%(asctime)s
• : Timestamp of the message
%(levelname)s
• : The level of the message
%(message)s
• : The content of the message
%(name)s
• : Logger name of the message

  formatter = logging.Formatter("%(asctime)s - %(levelname)s - %(message)s")
  console_handler.setFormatter(formatter)

Best Practices

Follow these best practices to effectively utilize the Logging module:

Choose an appropriate logging level to avoid logging too much or too little information.

• Use meaningful log messages that include sufficient information.
• Use file handlers in production environments to avoid losing console output.
• Check the logs regularly to understand application behavior and errors.

in conclusion

python

The Logging module is a powerful tool that can help you monitor and debug your application. By following this guide, you can quickly get started using the module and improve your application's logging practices.

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