Horde Log

PSR-3 compatible logging library with legacy API support.

Overview

Horde Log provides two distinct APIs:

1. PSR-3 Native Logger (src/, namespace Horde\Log)

   • Modern PSR-4 autoloaded implementation
   • Implements Psr\Log\LoggerInterface with Horde extensions
   • Structured logging with context arrays
   • Recommended for new code
   • Native systemd journal backend allows filtering on context attributes

2. Legacy Logger (lib/, class prefix Horde_Log_)

   • PSR-0 autoloaded implementation
   • Original Horde logging API (based on Zend_Log)
   • Maintained for backward compatibility

Both implementations can interoperate:

• Horde\Log\Handler\LoggerInterfaceHandler wraps any PSR-3 logger as a Horde classic handler
• Applications can inject PSR-3 loggers while maintaining legacy Horde log infrastructure

Installation

composer require horde/log

Basic Usage

PSR-3 Logger (Recommended)

use Horde\Log\Logger;
use Horde\Log\Handler\StreamHandler;
use Horde\Log\LogLevel;

$logger = new Logger();
$logger->addHandler(new StreamHandler('/var/log/app.log'));

// Structured logging with context
$logger->info('User authenticated', [
    'username' => 'alice',
    'session_id' => 'abc123',
    'success' => true,
]);

$logger->error('Authentication failed', [
    'username' => 'bob',
    'reason' => 'invalid_password',
]);

Legacy Logger

$logger = new Horde_Log_Logger(
    new Horde_Log_Handler_Stream('/var/log/app.log')
);

$logger->info('User authenticated: alice');
$logger->err('Authentication failed for bob');

Handlers

Handler	Legacy (lib/)	Modern (src/)	Notes
Stream	Horde_Log_Handler_Stream	StreamHandler	Write to files or streams
Syslog	Horde_Log_Handler_Syslog	SyslogHandler	System logger integration
Systemd Journal	-	SystemdJournalHandler	Modern only - Native systemd journal with structured data
Scribe	Horde_Log_Handler_Scribe	ScribeHandler	Apache Scribe logging
Firebug	Horde_Log_Handler_Firebug	FirebugHandler	Browser console logging (deprecated)
CLI	Horde_Log_Handler_Cli	CliHandler	Command-line output
Null	Horde_Log_Handler_Null	NullHandler	Discard all logs
Mock	Horde_Log_Handler_Mock	MockHandler	Testing purposes
PSR-3 Adapter	-	LoggerInterfaceHandler	Modern only - Wrap any PSR-3 logger

Filters

Filter	Legacy (lib/)	Modern (src/)	Notes
Minimum Level	Horde_Log_Filter_Level	MinimumLevelFilter	Log at or above priority (legacy name: Level)
Maximum Level	-	MaximumLevelFilter	Modern only - Log at or below priority
Exact Level	Horde_Log_Filter_ExactLevel	ExactLevelFilter	Log only specific priority
Message	Horde_Log_Filter_Message	MessageFilter	Regex-based message filtering
Constraint	Horde_Log_Filter_Constraint	ConstraintFilter	Custom constraint logic
Suppress	Horde_Log_Filter_Suppress	SuppressFilter	Suppress duplicate messages

Formatters

Formatter	Legacy (lib/)	Modern (src/)	Notes
Simple	Horde_Log_Formatter_Simple	SimpleFormatter	Basic text formatting
PSR-3	-	Psr3Formatter	Modern only - PSR-3 standard format with context
XML	Horde_Log_Formatter_Xml	XmlFormatter	XML structured output
CLI	Horde_Log_Formatter_Cli	CliFormatter	Colored terminal output

Upgrading

See doc/UPGRADING.md for migration guides from legacy API to PSR-3.

Requirements

• PHP 8.0 or later
• PSR-3 Logger Interface

License

BSD-2-Clause

Authors

• Mike Naberezny
• Chuck Hagenbuch
• Ralf Lang (current maintainer)