log

Logging Configuration and Management

A comprehensive logging utility module that provides flexible and configurable logging setup for Python applications, supporting both console and file-based logging with color formatting options.

Environment Variable

ROMI_APP_LOGGER is an optional environment variable that can be used to override the default logger name. When ROMI_APP_LOGGER is defined, the get_logger function will use its value as the logger name instead of the module‑derived name. This allows a single logger configuration to be shared across multiple components of the ROMI application.

Key Features

• Configurable log levels with sensible defaults
• Console logging with optional color formatting
• File-based logging with automatic file handling
• Dummy logger for testing/development
• Centralized logging configuration management
• Custom formatting options for log messages
• Dynamic log filename generation

Usage Examples

Basic usage

from plantdb.log import get_logger logger = get_logger(name) logger.info("Application started") INFO [main] Application started logger.error("An error occurred") ERROR [main] An error occurred

With custom configuration

logger = get_logger(name, log_level="DEBUG") logger.debug("Debugging information") DEBUG [main] Debugging information

With App logger

import os logger = get_logger('MyApp', log_level="INFO") os.environ.setdefault('ROMI_APP_LOGGER', 'fsdb_rest_api')

Can be called by another module, the environment variable will override logger name

another_logger = get_logger('MyModule') another_logger.info("Debugging information") INFO [fsdb_rest_api] Debugging information

get_console_handler

get_console_handler()

Creates and configures a console handler for logging that outputs to the standard output stream.

This handler uses a specific formatter for colored log messages.

Returns:

Type	Description
StreamHandler	The configured console logging handler with a colored formatter.

Source code in plantdb/commons/log.py

def get_console_handler():
    """Creates and configures a console handler for logging that outputs to the standard output stream.

    This handler uses a specific formatter for colored log messages.

    Returns
    -------
    logging.StreamHandler
        The configured console logging handler with a colored formatter.
    """
    console_handler = logging.StreamHandler(sys.stdout)
    console_handler.setFormatter(COLORED_FORMATTER)
    return console_handler

get_dummy_logger

get_dummy_logger(logger_name, log_level=DEFAULT_LOG_LEVEL)

Creates and configures a dummy logger with a console handler.

This function generates a logger instance associated with the specified name and log level. The logger is configured with a console handler to allow output of log statements to the console. It is typically used for basic logging setups where no file-based or external configurations are required.

Parameters:

Name	Type	Description	Default
logger_name	str	A name to use for the logger.	required
log_level	int or str	A logging level to set for the logger. Defaults to DEFAULT_LOG_LEVEL.	DEFAULT_LOG_LEVEL

Returns:

Type	Description
Logger	The configured logger instance with a console handler attached.

Source code in plantdb/commons/log.py

def get_dummy_logger(logger_name, log_level=DEFAULT_LOG_LEVEL):
    """Creates and configures a dummy logger with a console handler.

    This function generates a logger instance associated with the specified name and log level.
    The logger is configured with a console handler to allow output of log statements to the console.
    It is typically used for basic logging setups where no file-based or external configurations are required.

    Parameters
    ----------
    logger_name : str
        A name to use for the logger.
    log_level : int or str, optional
        A logging level to set for the logger. Defaults to ``DEFAULT_LOG_LEVEL``.

    Returns
    -------
    logging.Logger
        The configured logger instance with a console handler attached.
    """
    logger = logging.getLogger(logger_name)
    logger.setLevel(log_level)
    logger.addHandler(get_console_handler())
    return logger

get_file_handler

get_file_handler(log_file)

Creates and configures a file handler for logging.

This function initializes a logging file handler, sets its level, and applies a predefined formatter to it. The file handler writes log messages to the specified file in write mode. The log level determines the severity of messages that are captured by the handler.

Parameters:

Name	Type	Description	Default
log_file	str or Path	A path to the log file where log messages will be written.	required

Returns:

Type	Description
FileHandler	The configured logging file handler for capturing log messages.

Source code in plantdb/commons/log.py

def get_file_handler(log_file):
    """Creates and configures a file handler for logging.

    This function initializes a logging file handler, sets its level, and applies a predefined formatter to it.
    The file handler writes log messages to the specified file in write mode.
    The log level determines the severity of messages that are captured by the handler.

    Parameters
    ----------
    log_file : str or pathlib.Path
        A path to the log file where log messages will be written.

    Returns
    -------
    logging.FileHandler
        The configured logging file handler for capturing log messages.
    """
    file_handler = logging.FileHandler(log_file, mode='w')
    file_handler.setFormatter(FORMATTER)
    return file_handler

get_logger

get_logger(logger_name, log_file=None, log_level=DEFAULT_LOG_LEVEL)

Get a logger with a specific name and log level for console output.

This function retrieves an existing logger instance with the specified name, or creates a new one if none exists.

Parameters:

Name	Type	Description	Default
logger_name	str	A name to use for the logger. Typically derived from the module or component that generates the logs.	required
log_file	str or Path	A path to the file where log messages should be written. Defaults to None, in which case no file handler is added.	None
log_level	int or str	A logging level to set for the logger. Defaults to DEFAULT_LOG_LEVEL.	DEFAULT_LOG_LEVEL

Returns:

Type	Description
Logger	The configured logger instance ready to log messages with the specified settings.

Source code in plantdb/commons/log.py

def get_logger(logger_name, log_file=None, log_level=DEFAULT_LOG_LEVEL):
    """Get a logger with a specific name and log level for console output.

    This function retrieves an existing logger instance with the specified name, or creates a new one if none exists.

    Parameters
    ----------
    logger_name : str
        A name to use for the logger.
        Typically derived from the module or component that generates the logs.
    log_file : str or pathlib.Path, optional
        A path to the file where log messages should be written.
        Defaults to ``None``, in which case no file handler is added.
    log_level : int or str, optional
        A logging level to set for the logger. Defaults to ``DEFAULT_LOG_LEVEL``.

    Returns
    -------
    logging.Logger
        The configured logger instance ready to log messages with the specified settings.
    """
    name = logger_name.split(".")[-1]
    logger_name = os.getenv('ROMI_APP_LOGGER', name)
    if not logging.getLogger(logger_name).hasHandlers():
        return _get_logger(logger_name, log_file=log_file, log_level=log_level)
    return logging.getLogger(logger_name)