Create custom, chainable logging methods that emit log events when called.
Install with npm:
$ npm install log-events --saveCreate a new Logger constructor to allow
updating the prototype without affecting other contructors.
Factory for emitting log messages. This method is called internally for any emitter or mode method that is called as a function. To listen for events, listen for the emitter name or 'log' when a mode is called as a method.
Wildcard * may also be listened for and will get 2 arguments (name, stats) where
name is the emitter that was emitted and stats is the stats object for that event.
Params
name{String}: the name of the emitter event to emit. Example:infomessage{String}: Message intended to be emitted.returns{Object}Logger: for chaining
Events
emits:*Wildcard emitter that emits the emitter event name and stats object.emits:statsEmitter that emits the stats object for the specified name.
Example
// emit `info` when `info` is an emitter method
logger.info('message');
// emit `log` when `verbose` is a mode method
logger.verbose('message');
// listen for all events
logger.on('*', function(name, stats) {
console.log(name);
//=> info
});
logger.info('message');Add an emitter method to emit an event with the given name.
Params
name{String}: the name of the emitter event to emit.level{Number}: Priority level of the emitter. Higher numbers are less severe. (Default: 100)fn{Function}: Optional emitter function that can be used to modify an emitted message. Function may be an existing style function.returns{Object}this: for chaining
Events
emits:emitterEmits name and new emitter instance after adding the emitter method.
Example
// add a default `write` emitter
logger.emitter('write');
// add some styles
logger.style('red', function(msg) {
return colors.red(msg);
});
logger.style('cyan', function(msg) {
return colors.cyan(msg);
});
// add an `info` logger that colors the msg cyan
logger.emitter('info', logger.cyan);
// use the loggers:
logger.red.write('this is a red message');
logger.info('this is a cyan message');Add arbitrary modes to be used for creating namespaces for emitter methods.
Params
mode{String}: Mode to add to the logger.options{Object}: Options to describe the mode.options.type{String|Array}: Type of mode being created. Defaults tomode. Valid values are['mode', 'toggle']togglemode may be used to indicate a "flipped" state for another mode. e.g.not.verbosetogglemodes may not be used directly for emitting log events.fn{Function}: Optional style function that can be used to stylize an emitted message.returns{Object}this: for chaining
Events
emits:modeEmits the name and new mode instance after adding the mode method.
Example
// create a simple `verbose` mode
logger.mode('verbose');
// create a `not` toggle mode
logger.mode('not', {type: 'toggle'});
// create a `debug` mode that modifies the message
logger.mode('debug', function(msg) {
return '[DEBUG]: ' + msg;
});
// use the modes with styles and emitters from above:
logger.verbose.red.write('write a red message when verbose is true');
logger.not.verbose.info('write a cyan message when verbose is false');
logger.debug('write a message when debug is true');Mode constructor for making a mode object when
a mode is created with logger.mode()
Params
options{Object}: Options to configure the mode.options.name{String}: Required name of the modeoptions.type{String|Type}: Type of mode to create. Defaults tomode. Values may be['mode', 'toggle'].
Type of mode. Valid types are ['mode', 'toggle']
Example
console.log(verbose.type);
//=> "mode"
console.log(not.type);
//=> "toggle"Readable name of mode.
Example
console.log(verbose.name);
//=> "verbose"
console.log(not.name);
//=> "not"Optional modifier function that accepts a value and returns a modified value. When not present, an identity function is used to return the original value.
Example
var msg = "some error message";
// wrap message in ansi codes for "red"
msg = red.fn(msg);
console.log(msg);
//=> "\u001b[31msome error message\u001b[39m";Stats contructor that contains information about a chained event being built up.
Params
parent{Object}: Optional stats instance to inheritmodesandstylesfrom.
Example
{
// "not" => toggle, "verbose" => mode
modes: ['not', 'verbose'],
// "red" => modifier
styles: ['red'],
// specified when emitter is created
level: 1,
// name of emitter that will trigger an event
// in this case "red" will not trigger an event
name: 'subhead',
// arguments passed into emitter function "subhead"
args: ['foo', 'bar', 'baz']
}Add a mode to the modes array for this stats object.
Params
mode{Object}: Instance of a Mode to add to the stats object.returns{Object}this: for chaining.
Example
var verbose = new Mode({name: 'verbose'});
stats.addMode(verbose);Get the array of modes from the stats object. Optionally, pass a property in and return an array with only the property.
Params
prop{String}: Optional property to pick from the mode objects to return.returns{Array}: Array of modes or mode properties.
Example
var modes = stats.getModes();
//=> [{name: 'verbose'}]
var modeNames = stats.getModes('name');
//=> ['verbose']Add a style to the styles array for this stats object.
Params
style{String}: Name of style to add.returns{Object}this: for chaining.
Example
stats.addStyle('red');Sets the emitter for this stats object to indicate this is a complete stats object ready to be emitted.
Params
emitter{Object}: Instance of a Emitter to add to the stats object.returns{Object}this: for chaining.
Example
var info = new Emitter({name: 'info'});
stats.addEmitter(info);- falsey: Returns true if
valueis falsey. Works for strings, arrays andargumentsobjects with a… more | homepage - is-enabled: Using key paths that may contain "falsey" patterns, check if a property on an object… more | homepage
- verbalize: A pluggable logging utility with built-in colors, styles, and modes. | homepage
Pull requests and stars are always welcome. For bugs and feature requests, please create an issue.
Generate readme and API documentation with [verb][]:
$ npm install verb && npm run docsOr, if [verb][] is installed globally:
$ verbInstall dev dependencies:
$ npm install -d && npm testBrian Woodward
Copyright © 2016 Brian Woodward Released under the MIT license.
This file was generated by verb, v0.9.0, on March 07, 2016.