log4js-node/lib/appenders/multiprocess.js

135 lines
4.1 KiB
JavaScript

var log4js = require('../log4js'),
net = require('net'),
END_MSG = '__LOG4JS__';
/**
* Creates a server, listening on config.loggerPort, config.loggerHost.
* Output goes to config.actualAppender (config.appender is used to
* set up that appender).
*/
function logServer(config) {
/**
* Takes a utf-8 string, returns an object with
* the correct log properties.
*/
function deserializeLoggingEvent(clientSocket, msg) {
var loggingEvent;
try {
loggingEvent = JSON.parse(msg);
loggingEvent.startTime = new Date(loggingEvent.startTime);
loggingEvent.level.toString = function levelToString() {
return loggingEvent.level.levelStr;
};
} catch (e) {
// JSON.parse failed, just log the contents probably a naughty.
loggingEvent = {
startTime: new Date(),
categoryName: 'log4js',
level: { toString: function () {
return 'ERROR';
}
},
data: [ 'Unable to parse log:', msg ]
};
}
loggingEvent.remoteAddress = clientSocket.remoteAddress;
loggingEvent.remotePort = clientSocket.remotePort;
return loggingEvent;
}
var actualAppender = config.actualAppender,
server = net.createServer(function serverCreated(clientSocket) {
clientSocket.setEncoding('utf8');
clientSocket.on('connect', function clientConnected() {
var logMessage = '';
function logTheMessage(msg) {
if (logMessage.length > 0) {
actualAppender(deserializeLoggingEvent(clientSocket, msg));
}
}
function chunkReceived(chunk) {
var event;
logMessage += chunk || '';
if (logMessage.indexOf(END_MSG) > -1) {
event = logMessage.substring(0, logMessage.indexOf(END_MSG));
logTheMessage(event);
logMessage = logMessage.substring(event.length + END_MSG.length) || '';
//check for more, maybe it was a big chunk
chunkReceived();
}
}
clientSocket.on('data', chunkReceived);
clientSocket.on('end', chunkReceived);
});
});
server.listen(config.loggerPort || 5000, config.loggerHost || 'localhost');
return actualAppender;
}
function workerAppender(config) {
var canWrite = false,
buffer = [],
socket;
createSocket();
function createSocket() {
socket = net.createConnection(config.loggerPort || 5000, config.loggerHost || 'localhost');
socket.on('connect', function() {
emptyBuffer();
canWrite = true;
});
socket.on('timeout', socket.end.bind(socket));
//don't bother listening for 'error', 'close' gets called after that anyway
socket.on('close', createSocket);
}
function emptyBuffer() {
var evt;
while ((evt = buffer.shift())) {
write(evt);
}
}
function write(loggingEvent) {
socket.write(JSON.stringify(loggingEvent), 'utf8');
socket.write(END_MSG, 'utf8');
}
return function log(loggingEvent) {
if (canWrite) {
write(loggingEvent);
} else {
buffer.push(loggingEvent);
}
};
}
function createAppender(config) {
if (config.mode === 'master') {
return logServer(config);
} else {
return workerAppender(config);
}
}
function configure(config) {
var actualAppender;
if (config.appender && config.mode === 'master') {
log4js.loadAppender(config.appender.type);
actualAppender = log4js.appenderMakers[config.appender.type](config.appender);
config.actualAppender = actualAppender;
}
return createAppender(config);
}
exports.appender = createAppender;
exports.configure = configure;