addLevel

addLevel is a method used in the Winston logging library for Node.js. It allows developers to define and add custom log levels to a logger instance. Winston supports a set of predefined levels—such as error, warn, info, http, verbose, debug, and silly—each associated with a numeric priority. The addLevel method adds a new level with a specified name and priority.

The method typically takes an object argument with two properties: level, a string identifier for the level, and priority, an integer indicating the level’s importance. When a level is added, Winston automatically generates corresponding logging functions (e.g., logger.myLevel()) that can be called like the built‑in ones. The new level’s color and formatting can also be configured through Winston’s colorize and format options.

A common use case for addLevel is to create a level such as 'audit' with a priority lower than error but higher than warn, enabling fine‑grained control over log filtering. It can also help integrate with external monitoring systems that expect logs at specific severity levels.

Documentation for addLevel is available in the official Winston API reference, which includes examples of adding, removing, and adjusting log levels dynamically. It is useful for projects requiring custom severity categorization beyond the out‑of‑the‑box levels.