jQuery.Logger

A simple but powerful logging plugin for jQuery with namespaces.

Examples

Create a (global) logger and log something:

var logger = $.Logger();
 
/**
 * simply log something
 */
logger.debug("my first log");
// => [2015-03-16 14:38:55.817] DEBUG - global - my first log
 
/*
 * disable, log and enable again
 */
logger.disable();
logger.debug("another log");
// nothing happens
logger.enable();
 
/**
 * set the level
 */
logger.level("info");
logger.debug("foo bar");
// nothing happens
logger.info("but this time");
// => [2015-03-16 14:38:56.193] INFO - global - but this time
 
 
/**
 * show name and namespace
 */
logger.name();
// => "global"
logger.namespace();
// => "global";

Create a child logger:

var myLogger = $.Logger("foo");
 
/**
 * simply log something
 */
myLogger.info("foo's first log");
// => [2015-03-16 14:38:56.602] INFO - foo - foo's first log
 
 
/**
 * show parentage using the (global) logger defined above
 */
myLogger.parent() == logger;
// => true
 
// logger.child("foo") == myLogger;
// => true
 

Configuration

// configure $.Logger _before_ you create any logger instance
// (these are the default options)
$.Logger({
  // name of the global namespace
  global: "global",
 
  // delimitter that seperates namespaces
  delimitter: ".",
 
  // use appropriate console logging methods instead of the standard log method,
  useConsoleMethods: true,
 
  // show namespaces in logs
  showNamespace: true,
 
  // show timestamps in logs
  showTimestamp: true,
 
  // experimental
  // show file name and line number of the origin
  showOrigin: true,
  
  // experimental
  // cut query string from origin
  cutQuery: true
});

API

• $.Logger([namespace|options])

  If options are passed, the logger options are extended and the $.Logger object is returned. If a namespace is passed, a new logger instance with that namespace is created and returned. When no argument is given, the global logger is returned. Logger parentage is built automatically. A namespace consists of a number of logger names seperated by a delimitter. Example: namespace "foo.bar" => logger "global" -> logger "foo" -> logger "bar". Note that the global namespace ("global" in this example) is always prepended.

• namespace()

  Returns the namespace.

• name()

  Returns the name.

• parent()

  Returns the parent logger, or null when invoked on the global logger.

• children()

  Return all child loggers mapped to their names.

• child(name)

  Return a child logger given by name.

• enabled()

  Returns the state of the logger.

• enable()

  Enable the logger and all its child loggers.

• disable()

  Disable this and all its child loggers.

• level([level])

  When level is given, the log level is set to that value. Possible values: "all", "debug", "info", "warning", "error", "fatal". When no argument is passed, the current log level is returned.

• levels()

  Returns all valid log levels mapped to their numerical representation.

• options()

  Returns the current options.

• log(level, ...)

  Log arguments with a given level.

• all | debug | info | warning | error | fatal(...)

  Shorthands that wrap around log for specific levels.

• originOffset([offset]), experimental

  The context that invoked a log (the origin) is determined by parsing the stack trace of a newly created error instance. The first few lines in that stack describe the internal invocation queue of this plugin. In the current implementation, the 5th line is the one that caused the actual log. However, in some cases (e.g. when logging a deprecation warning) it is useful to see the origin of an earlier invocation in the queue. This can be achieved by setting originOffset to a numerical value that is added to the stack line index (5th line -> 4) for the next log. After that, the offset is reset to 0 again.

  When offset is given, the origin offset is set to that value. When no argument is passed, the current origin offset is returned.

Development

• Source hosted at GitHub
• Report issues, questions, feature requests on GitHub Issues

License

MIT.

Authors

Marcel R. (riga)