log4js-node/lib/connect-logger.js
2011-07-19 09:08:15 +10:00

114 lines
3.3 KiB
JavaScript

var levels = require("./levels");
/**
* Log requests with the given `options` or a `format` string.
*
* Options:
*
* - `format` Format string, see below for tokens
* - `level` A log4js levels instance.
*
* Tokens:
*
* - `:req[header]` ex: `:req[Accept]`
* - `:res[header]` ex: `:res[Content-Length]`
* - `:http-version`
* - `:response-time`
* - `:remote-addr`
* - `:date`
* - `:method`
* - `:url`
* - `:referrer`
* - `:user-agent`
* - `:status`
*
* @param {String|Function|Object} format or options
* @return {Function}
* @api public
*/
function getLogger(logger4js, options) {
if ('object' == typeof options) {
options = options || {};
} else if (options) {
options = { format: options };
} else {
options = {};
}
var thislogger = logger4js
, level = levels.toLevel(options.level, levels.INFO)
, fmt = options.format || ':remote-addr - - ":method :url HTTP/:http-version" :status :content-length ":referrer" ":user-agent"';
return function (req, res, next) {
// mount safety
if (req._logging) return next();
if (thislogger.isLevelEnabled(level)) {
var start = +new Date
, statusCode
, writeHead = res.writeHead
, end = res.end
, url = req.originalUrl;
// flag as logging
req._logging = true;
// proxy for statusCode.
res.writeHead = function(code, headers){
res.writeHead = writeHead;
res.writeHead(code, headers);
res.__statusCode = statusCode = code;
res.__headers = headers || {};
};
// proxy end to output a line to the provided logger.
res.end = function(chunk, encoding) {
res.end = end;
res.end(chunk, encoding);
res.responseTime = +new Date - start;
if ('function' == typeof fmt) {
var line = fmt(req, res, function(str){ return format(str, req, res); });
if (line) thislogger.log(level, line);
} else {
thislogger.log(level, format(fmt, req, res));
}
};
next();
}
};
}
/**
* Return formatted log line.
*
* @param {String} str
* @param {IncomingMessage} req
* @param {ServerResponse} res
* @return {String}
* @api private
*/
function format(str, req, res) {
return str
.replace(':url', req.originalUrl)
.replace(':method', req.method)
.replace(':status', res.__statusCode || res.statusCode)
.replace(':response-time', res.responseTime)
.replace(':date', new Date().toUTCString())
.replace(':referrer', req.headers['referer'] || req.headers['referrer'] || '')
.replace(':http-version', req.httpVersionMajor + '.' + req.httpVersionMinor)
.replace(':remote-addr', req.socket && (req.socket.remoteAddress || (req.socket.socket && req.socket.socket.remoteAddress)))
.replace(':user-agent', req.headers['user-agent'] || '')
.replace(':content-length', (res._headers && res._headers['content-length']) || (res.__headers && res.__headers['Content-Length']) || '-')
.replace(/:req\[([^\]]+)\]/g, function(_, field){ return req.headers[field.toLowerCase()]; })
.replace(/:res\[([^\]]+)\]/g, function(_, field){
return res._headers
? (res._headers[field.toLowerCase()] || res.__headers[field])
: (res.__headers && res.__headers[field]);
});
}
exports.connectLogger = getLogger;