/ 
glog-1.0.5-3
/ glog::logger

NAME

glog::logger - Object-Oriented Logging Implementation

SYNOPSIS

use glog::logger;

# Create a logger instance
my $logger = glog::logger->new;

# Set log level
$logger->LogLevel(5);  # Enable debug logging

# Log messages
$logger->LogInfo("Application started");
$logger->LogDebug("Debug details: x=42");
$logger->LogWarn("Warning: low disk space");
$logger->LogErr("Error: cannot open file");
$logger->LogDie("Fatal error!");

# Formatted logging
$logger->LogFormat(3, "User %s logged in at %d", "alice", time);

# Log to a file
$logger->LogFile("app.log");
$logger->LogInfo("Logging to file");
$logger->LogFile(undef);  # Revert to STDERR

DESCRIPTION

glog::logger is a robust, Pure Perl object-oriented logging module that forms the core of the logging system. It provides a flexible, high-performance logging mechanism for applications requiring structured output at various severity levels (ERROR, WARN, INFO, DEBUG). The module is designed to be lightweight, portable, and easy to integrate into both small scripts and large systems.

glog::logger handles all logging logic, including timestamp generation, message formatting, and output management (to STDERR or a file). It is typically used indirectly through the glog functional interface, but can be instantiated directly for applications needing multiple logger instances or custom configurations.

glog::logger is optimized for speed, reliability, and minimal dependencies, making it an ideal choice for Pure Perl environments.

METHODS

  • new()

    Creates a new glog::logger instance with default settings (log level 3, output to STDERR).

    my $logger = glog::logger->new;

  • LogLevel($level)

    Sets or retrieves the current log level (0-9). If $level is provided, it updates the log level; otherwise, it returns the current level. The default level is 3 (INFO).

    $logger->LogLevel(5);  # Enable DEBUG logging
my $current = $logger->LogLevel();  # Get current level

  • Log($level, $message)

    Logs a message at the specified level if it is less than or equal to the current log level. The message is prefixed with a timestamp and level name.

    $logger->Log(3, "Processing started");

  • LogFormat($level, $format, @args)

    Logs a formatted message (using sprintf) at the specified level if allowed by the current log level.

    $logger->LogFormat(3, "Processed %d items in %s", 42, "2s");

  • LogFile($path)

    Configures logging to a file. If $path is provided, logs are appended to the specified file. If undef is passed, logging reverts to STDERR.

    $logger->LogFile("app.log");  # Log to app.log
$logger->LogFile(undef);      # Revert to STDERR

  • LogDie($message)

    Logs an ERROR message (level 1) and terminates the program with die.

    $logger->LogDie("Cannot connect to database");

  • LogWarn($message)

    Logs a WARN message (level 2).

    $logger->LogWarn("Configuration file not found, using defaults");

  • LogInfo($message)

    Logs an INFO message (level 3).

    $logger->LogInfo("Server started on port 8080");

  • LogDebug($message)

    Logs a DEBUG message (level 5).

    $logger->LogDebug("Variable x = 42");

  • LogErr($message)

    Logs an ERROR message (level 1) without terminating the program.

    $logger->LogErr("Failed to read input file");

LOG LEVELS

The module supports the following log levels:

  • 1: ERROR (critical errors)

  • 2: WARN (warnings)

  • 3: INFO (informational messages)

  • 5: DEBUG (detailed debugging information)

Messages are only logged if their level is less than or equal to the current log level set by LogLevel.

OUTPUT FORMAT

Log messages follow a consistent format:

[YYYY-MM-DD HH:MM:SS.mmm] LEVEL message

Example output:

[2025-04-25 20:15:23.456] INFO Application started
[2025-04-25 20:15:23.789] ERROR Cannot open file

The timestamp includes millisecond precision, generated using Time::HiRes.

PERFORMANCE OPTIMIZATIONS

glog::logger is engineered for high performance:

  • **Early Level Checks**: Skips logging if the message level exceeds the current log level, minimizing processing.

  • **Efficient Timestamps**: Uses Time::HiRes for precise, low-overhead timestamp generation.

  • **Lightweight Object**: Minimal memory footprint with simple hash-based objects.

  • **File Handling**: Efficient append-mode file operations with error checking.

LIMITATIONS

  • No built-in log rotation or advanced file management.

  • No native threading support; use caution in multi-threaded environments.

  • File logging is append-only, without automatic size or rotation management.

DEPENDENCIES

  • Time::HiRes (for high-resolution timestamps)

  • POSIX (for timestamp formatting)

  • gerr (for error handling with Die)

No external CPAN dependencies are required beyond these standard modules.

INTEGRATION WITH DOMERO TOOLS

glog::logger is the core logging engine for the Domero Tools suite, used by modules like glog. It provides a standardized logging mechanism for debugging, monitoring, and error reporting across the ecosystem.

Example with direct usage:

use glog::logger;
use gcrc;

my $logger = glog::logger->new;
$logger->LogLevel(5);  # Enable debug
my $crc = enc_crc32('CRC32', "Hello World");
$logger->LogInfo("Computed CRC32: $crc");
$logger->LogDebug("Validating CRC32...");
is_crc32('CRC32', "Hello World", $crc) or $logger->LogDie("CRC mismatch");

AUTHOR

OnEhIppY <domerosoftware@gmail.com>, Domero Software

SEE ALSO

  • glog - The functional logging interface built on glog::logger.

VERSION

1.0.5

LICENSE

This module is distributed under the MIT License. See the LICENSE file in the distribution for details.