Monolog

Monolog is a term that can refer to two distinct concepts in different domains. In drama and rhetoric, a monologue (often spelled monolog) is a long speech delivered by a single character to reveal thoughts or advance the plot. In software development, Monolog is a PHP logging library designed to send log messages to multiple destinations.

In drama and literature, a monologue is a speech delivered by one character, addressing other characters or the audience. It can reveal inner thoughts, provide exposition, or offer critique. A monologue differs from a soliloquy, which is spoken by a character alone on stage or under the assumption that others cannot hear.

Monolog, the PHP library, is a popular open-source logging framework for PHP. It provides a flexible logging system that supports multiple handlers and formatters, allowing messages to be written to files, databases, or external services. Monolog implements a PSR-3 compatible logger interface and can route the same log record to several destinations simultaneously. It includes a range of handlers such as StreamHandler for file streams, RotatingFileHandler for timed backups, SyslogHandler for system logging, and various others for Slack, email, or message queues. Processors can enrich records with extra context, and formatters define how records are rendered.

Originating in the PHP ecosystem, Monolog was designed to streamline logging in projects and to integrate with major frameworks through Composer. It is widely adopted in modern PHP applications and serves as a general-purpose, extensible solution for monitoring and debugging.