Class: Logger

Logger

An object used to log debugging messages. Loggers use a hierarchical, dot-separated naming scheme. For instance, "foo" is considered the parent of the "foo.bar" and an ancestor of "foo.bar.baz".

Each logger may be assigned a log level, which controls which level of messages will be reported to the handlers attached to this instance. If a log level is not explicitly set on a logger, it will inherit its parent.

This class should never be directly instantiated. Instead, users should obtain logger references using the getLogger() function.

Constructor

new Logger(name, opt_levelopt)

Parameters:

Name	Type	Attributes	Description
`name`	string		the name of this logger.
`opt_level`	Level	<optional>	the initial level for this logger.

Source: lib/logging.js, line 257

Methods

addHandler(handler)

Adds a handler to this logger. The handler will be invoked for each message logged with this instance, or any of its descendants.

Parameters:

Name	Type	Description
`handler`	function	the handler to add.

Source: lib/logging.js, line 325

debug(loggable)

Logs a message at the Level.DEBUG log level.

Parameters:

Name	Type	Description
`loggable`	string \| function	the message to log, or a function that will return the message.

Source: lib/logging.js, line 435

deprecate(id, message)

Logs a deprecation notice at the Level.WARNING log level, once per id for this logger's lifetime — a repeat call with the same id is a no-op, matching the once-only behavior util.deprecate gives by call-site identity, but keyed on a stable id instead so it survives being wrapped, rebound, or called through multiple paths.

id is only claimed once the notice is actually loggable at this logger's effective level — under the default Level.OFF root level, a call here logs nothing and leaves id unclaimed, so a later call (once logging is enabled) still gets to report it instead of finding it already silently used up.

Parameters:

Name	Type	Description
`id`	string	a stable, non-empty identifier for this deprecation (e.g. `'webdriver-getBidi'`), distinct from the message text so tooling can key off it even if the wording changes later.
`message`	string	the deprecation notice to log.

Source: lib/logging.js, line 416

Throws:

if id is empty.
Type TypeError

fine(loggable)

Logs a message at the Level.FINE log level.

Parameters:

Name	Type	Description
`loggable`	string \| function	the message to log, or a function that will return the message.

Source: lib/logging.js, line 444

finer(loggable)

Logs a message at the Level.FINER log level.

Parameters:

Name	Type	Description
`loggable`	string \| function	the message to log, or a function that will return the message.

Source: lib/logging.js, line 453

finest(loggable)

Logs a message at the Level.FINEST log level.

Parameters:

Name	Type	Description
`loggable`	string \| function	the message to log, or a function that will return the message.

Source: lib/logging.js, line 462

getEffectiveLevel() → (non-null) {Level}

Source: lib/logging.js, line 300

Returns:

the effective level for this logger.

Type:: Level

getLevel() → {Level}

Source: lib/logging.js, line 293

Returns:

the log level for this logger.

Type:: Level

getName() → {string}

Source: lib/logging.js, line 280

Returns:

the name of this logger.

Type:: string

info(loggable)

Logs a message at the Level.INFO log level.

Parameters:

Name	Type	Description
`loggable`	string \| function	the message to log, or a function that will return the message.

Source: lib/logging.js, line 394

isLoggable(levelnon-null) → {boolean}

Parameters:

Name	Type	Description
`level`	Level	the level to check.

Source: lib/logging.js, line 315

Returns:

whether messages recorded at the given level are loggable by this instance.

Type:: boolean

log(levelnon-null, loggable)

Logs a message at the given level. The message may be defined as a string or as a function that will return the message. If a function is provided, it will only be invoked if this logger's effective log level includes the given level.

Parameters:

Name	Type	Description
`level`	Level	the level at which to log the message.
`loggable`	string \| function	the message to log, or a function that will return the message.

Source: lib/logging.js, line 356

removeHandler(handler) → {boolean}

Removes a handler from this logger.

Parameters:

Name	Type	Description
`handler`	function	the handler to remove.

Source: lib/logging.js, line 338

Returns:

whether a handler was successfully removed.

Type:: boolean

setLevel(level)

Parameters:

Name	Type	Description
`level`	Level	the new level for this logger, or `null` if the logger should inherit its level from its parent logger.

Source: lib/logging.js, line 288

severe(loggable)

Logs a message at the Level.SEVERE log level.

Parameters:

Name	Type	Description
`loggable`	string \| function	the message to log, or a function that will return the message.

Source: lib/logging.js, line 376

warning(loggable)

Logs a message at the Level.WARNING log level.

Parameters:

Name	Type	Description
`loggable`	string \| function	the message to log, or a function that will return the message.

Source: lib/logging.js, line 385