319 lines
9 KiB
JavaScript
319 lines
9 KiB
JavaScript
/**
|
|
* Cross-browser support for logging in a web application.
|
|
*
|
|
* @author David I. Lehn <dlehn@digitalbazaar.com>
|
|
*
|
|
* Copyright (c) 2008-2013 Digital Bazaar, Inc.
|
|
*/
|
|
var forge = require('./forge');
|
|
require('./util');
|
|
|
|
/* LOG API */
|
|
module.exports = forge.log = forge.log || {};
|
|
|
|
/**
|
|
* Application logging system.
|
|
*
|
|
* Each logger level available as it's own function of the form:
|
|
* forge.log.level(category, args...)
|
|
* The category is an arbitrary string, and the args are the same as
|
|
* Firebug's console.log API. By default the call will be output as:
|
|
* 'LEVEL [category] <args[0]>, args[1], ...'
|
|
* This enables proper % formatting via the first argument.
|
|
* Each category is enabled by default but can be enabled or disabled with
|
|
* the setCategoryEnabled() function.
|
|
*/
|
|
// list of known levels
|
|
forge.log.levels = [
|
|
'none', 'error', 'warning', 'info', 'debug', 'verbose', 'max'];
|
|
// info on the levels indexed by name:
|
|
// index: level index
|
|
// name: uppercased display name
|
|
var sLevelInfo = {};
|
|
// list of loggers
|
|
var sLoggers = [];
|
|
/**
|
|
* Standard console logger. If no console support is enabled this will
|
|
* remain null. Check before using.
|
|
*/
|
|
var sConsoleLogger = null;
|
|
|
|
// logger flags
|
|
/**
|
|
* Lock the level at the current value. Used in cases where user config may
|
|
* set the level such that only critical messages are seen but more verbose
|
|
* messages are needed for debugging or other purposes.
|
|
*/
|
|
forge.log.LEVEL_LOCKED = (1 << 1);
|
|
/**
|
|
* Always call log function. By default, the logging system will check the
|
|
* message level against logger.level before calling the log function. This
|
|
* flag allows the function to do its own check.
|
|
*/
|
|
forge.log.NO_LEVEL_CHECK = (1 << 2);
|
|
/**
|
|
* Perform message interpolation with the passed arguments. "%" style
|
|
* fields in log messages will be replaced by arguments as needed. Some
|
|
* loggers, such as Firebug, may do this automatically. The original log
|
|
* message will be available as 'message' and the interpolated version will
|
|
* be available as 'fullMessage'.
|
|
*/
|
|
forge.log.INTERPOLATE = (1 << 3);
|
|
|
|
// setup each log level
|
|
for(var i = 0; i < forge.log.levels.length; ++i) {
|
|
var level = forge.log.levels[i];
|
|
sLevelInfo[level] = {
|
|
index: i,
|
|
name: level.toUpperCase()
|
|
};
|
|
}
|
|
|
|
/**
|
|
* Message logger. Will dispatch a message to registered loggers as needed.
|
|
*
|
|
* @param message message object
|
|
*/
|
|
forge.log.logMessage = function(message) {
|
|
var messageLevelIndex = sLevelInfo[message.level].index;
|
|
for(var i = 0; i < sLoggers.length; ++i) {
|
|
var logger = sLoggers[i];
|
|
if(logger.flags & forge.log.NO_LEVEL_CHECK) {
|
|
logger.f(message);
|
|
} else {
|
|
// get logger level
|
|
var loggerLevelIndex = sLevelInfo[logger.level].index;
|
|
// check level
|
|
if(messageLevelIndex <= loggerLevelIndex) {
|
|
// message critical enough, call logger
|
|
logger.f(logger, message);
|
|
}
|
|
}
|
|
}
|
|
};
|
|
|
|
/**
|
|
* Sets the 'standard' key on a message object to:
|
|
* "LEVEL [category] " + message
|
|
*
|
|
* @param message a message log object
|
|
*/
|
|
forge.log.prepareStandard = function(message) {
|
|
if(!('standard' in message)) {
|
|
message.standard =
|
|
sLevelInfo[message.level].name +
|
|
//' ' + +message.timestamp +
|
|
' [' + message.category + '] ' +
|
|
message.message;
|
|
}
|
|
};
|
|
|
|
/**
|
|
* Sets the 'full' key on a message object to the original message
|
|
* interpolated via % formatting with the message arguments.
|
|
*
|
|
* @param message a message log object.
|
|
*/
|
|
forge.log.prepareFull = function(message) {
|
|
if(!('full' in message)) {
|
|
// copy args and insert message at the front
|
|
var args = [message.message];
|
|
args = args.concat([] || message['arguments']);
|
|
// format the message
|
|
message.full = forge.util.format.apply(this, args);
|
|
}
|
|
};
|
|
|
|
/**
|
|
* Applies both preparseStandard() and prepareFull() to a message object and
|
|
* store result in 'standardFull'.
|
|
*
|
|
* @param message a message log object.
|
|
*/
|
|
forge.log.prepareStandardFull = function(message) {
|
|
if(!('standardFull' in message)) {
|
|
// FIXME implement 'standardFull' logging
|
|
forge.log.prepareStandard(message);
|
|
message.standardFull = message.standard;
|
|
}
|
|
};
|
|
|
|
// create log level functions
|
|
if(true) {
|
|
// levels for which we want functions
|
|
var levels = ['error', 'warning', 'info', 'debug', 'verbose'];
|
|
for(var i = 0; i < levels.length; ++i) {
|
|
// wrap in a function to ensure proper level var is passed
|
|
(function(level) {
|
|
// create function for this level
|
|
forge.log[level] = function(category, message/*, args...*/) {
|
|
// convert arguments to real array, remove category and message
|
|
var args = Array.prototype.slice.call(arguments).slice(2);
|
|
// create message object
|
|
// Note: interpolation and standard formatting is done lazily
|
|
var msg = {
|
|
timestamp: new Date(),
|
|
level: level,
|
|
category: category,
|
|
message: message,
|
|
'arguments': args
|
|
/*standard*/
|
|
/*full*/
|
|
/*fullMessage*/
|
|
};
|
|
// process this message
|
|
forge.log.logMessage(msg);
|
|
};
|
|
})(levels[i]);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Creates a new logger with specified custom logging function.
|
|
*
|
|
* The logging function has a signature of:
|
|
* function(logger, message)
|
|
* logger: current logger
|
|
* message: object:
|
|
* level: level id
|
|
* category: category
|
|
* message: string message
|
|
* arguments: Array of extra arguments
|
|
* fullMessage: interpolated message and arguments if INTERPOLATE flag set
|
|
*
|
|
* @param logFunction a logging function which takes a log message object
|
|
* as a parameter.
|
|
*
|
|
* @return a logger object.
|
|
*/
|
|
forge.log.makeLogger = function(logFunction) {
|
|
var logger = {
|
|
flags: 0,
|
|
f: logFunction
|
|
};
|
|
forge.log.setLevel(logger, 'none');
|
|
return logger;
|
|
};
|
|
|
|
/**
|
|
* Sets the current log level on a logger.
|
|
*
|
|
* @param logger the target logger.
|
|
* @param level the new maximum log level as a string.
|
|
*
|
|
* @return true if set, false if not.
|
|
*/
|
|
forge.log.setLevel = function(logger, level) {
|
|
var rval = false;
|
|
if(logger && !(logger.flags & forge.log.LEVEL_LOCKED)) {
|
|
for(var i = 0; i < forge.log.levels.length; ++i) {
|
|
var aValidLevel = forge.log.levels[i];
|
|
if(level == aValidLevel) {
|
|
// set level
|
|
logger.level = level;
|
|
rval = true;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
return rval;
|
|
};
|
|
|
|
/**
|
|
* Locks the log level at its current value.
|
|
*
|
|
* @param logger the target logger.
|
|
* @param lock boolean lock value, default to true.
|
|
*/
|
|
forge.log.lock = function(logger, lock) {
|
|
if(typeof lock === 'undefined' || lock) {
|
|
logger.flags |= forge.log.LEVEL_LOCKED;
|
|
} else {
|
|
logger.flags &= ~forge.log.LEVEL_LOCKED;
|
|
}
|
|
};
|
|
|
|
/**
|
|
* Adds a logger.
|
|
*
|
|
* @param logger the logger object.
|
|
*/
|
|
forge.log.addLogger = function(logger) {
|
|
sLoggers.push(logger);
|
|
};
|
|
|
|
// setup the console logger if possible, else create fake console.log
|
|
if(typeof(console) !== 'undefined' && 'log' in console) {
|
|
var logger;
|
|
if(console.error && console.warn && console.info && console.debug) {
|
|
// looks like Firebug-style logging is available
|
|
// level handlers map
|
|
var levelHandlers = {
|
|
error: console.error,
|
|
warning: console.warn,
|
|
info: console.info,
|
|
debug: console.debug,
|
|
verbose: console.debug
|
|
};
|
|
var f = function(logger, message) {
|
|
forge.log.prepareStandard(message);
|
|
var handler = levelHandlers[message.level];
|
|
// prepend standard message and concat args
|
|
var args = [message.standard];
|
|
args = args.concat(message['arguments'].slice());
|
|
// apply to low-level console function
|
|
handler.apply(console, args);
|
|
};
|
|
logger = forge.log.makeLogger(f);
|
|
} else {
|
|
// only appear to have basic console.log
|
|
var f = function(logger, message) {
|
|
forge.log.prepareStandardFull(message);
|
|
console.log(message.standardFull);
|
|
};
|
|
logger = forge.log.makeLogger(f);
|
|
}
|
|
forge.log.setLevel(logger, 'debug');
|
|
forge.log.addLogger(logger);
|
|
sConsoleLogger = logger;
|
|
} else {
|
|
// define fake console.log to avoid potential script errors on
|
|
// browsers that do not have console logging
|
|
console = {
|
|
log: function() {}
|
|
};
|
|
}
|
|
|
|
/*
|
|
* Check for logging control query vars in current URL.
|
|
*
|
|
* console.level=<level-name>
|
|
* Set's the console log level by name. Useful to override defaults and
|
|
* allow more verbose logging before a user config is loaded.
|
|
*
|
|
* console.lock=<true|false>
|
|
* Lock the console log level at whatever level it is set at. This is run
|
|
* after console.level is processed. Useful to force a level of verbosity
|
|
* that could otherwise be limited by a user config.
|
|
*/
|
|
if(sConsoleLogger !== null &&
|
|
typeof window !== 'undefined' && window.location
|
|
) {
|
|
var query = new URL(window.location.href).searchParams;
|
|
if(query.has('console.level')) {
|
|
// set with last value
|
|
forge.log.setLevel(
|
|
sConsoleLogger, query.get('console.level').slice(-1)[0]);
|
|
}
|
|
if(query.has('console.lock')) {
|
|
// set with last value
|
|
var lock = query.get('console.lock').slice(-1)[0];
|
|
if(lock == 'true') {
|
|
forge.log.lock(sConsoleLogger);
|
|
}
|
|
}
|
|
}
|
|
|
|
// provide public access to console logger
|
|
forge.log.consoleLogger = sConsoleLogger;
|