standard-logging

Standard Logging Example

This example demonstrates how to use Reforge's LoggerFilter to dynamically control log levels for standard Python logging.

Features

• Dynamic log level control through Reforge configuration
• No application restart required to change log levels
• Works with standard Python logging module
• Can target specific loggers by name using context-based rules

Setup

1. Install dependencies:

   poetry install --no-root

2. Set your Reforge SDK key (or use local-only mode as in the example):

   export REFORGE_SDK_KEY=your-sdk-key-here

3. Create a log level config in your Reforge dashboard:

   • Config key: log-levels.default
   • Type: LOG_LEVEL_V2
   • Default value: INFO (or your preferred level)

Running the Example

poetry run python standard_logging_example.py

The example will log messages at all levels (DEBUG, INFO, WARNING, ERROR) every second.

Dynamic Control

While the example is running, you can:

1. Change the log level in your Reforge dashboard
2. See the output change in real-time without restarting the application
3. Use context-based rules to set different levels for different loggers

For example, you could create rules like:

• Set DEBUG level for reforge.python.* loggers
• Set ERROR level for all other loggers
• Set INFO level during business hours, DEBUG level at night

How It Works

The LoggerFilter integrates with Python's standard logging by:

1. Implementing the logging.Filter interface
2. Querying Reforge config for the log level on each log message
3. Returning True (allow) or False (block) based on the configured level
4. Using a context containing the logger name for targeted rules

Advanced Usage

You can customize the logger name lookup by subclassing LoggerFilter:

class CustomLoggerFilter(LoggerFilter):
    def logger_name(self, record: logging.LogRecord) -> str:
        # Custom logic to derive logger name
        return record.name.replace("myapp", "mycompany")