log4js-node/lib/appenders/clustered.js
Vladimir Mitev 2daf29b400 Clusterred appender should consider the categories.
It turns out that whenever the clusterred appender is used the log event is passed to all actual appenders.
The actual appender's category is ignored.

Signed-off-by: Vladimir Mitev <idalv@users.noreply.github.com>
2014-05-20 13:45:46 +03:00

130 lines
3.8 KiB
JavaScript
Executable File

"use strict";
var cluster = require('cluster');
var log4js = require('../log4js');
/**
* Takes a loggingEvent object, returns string representation of it.
*/
function serializeLoggingEvent(loggingEvent) {
// JSON.stringify(new Error('test')) returns {}, which is not really useful for us.
// The following allows us to serialize errors correctly.
for (var i = 0; i < loggingEvent.data.length; i++) {
var item = loggingEvent.data[i];
if (item && item.stack && JSON.stringify(item) === '{}') { // Validate that we really are in this case
loggingEvent.data[i] = {stack : item.stack};
}
}
return JSON.stringify(loggingEvent);
}
/**
* Takes a string, returns an object with
* the correct log properties.
*
* This method has been "borrowed" from the `multiprocess` appender
* by `nomiddlename` (https://github.com/nomiddlename/log4js-node/blob/master/lib/appenders/multiprocess.js)
*
* Apparently, node.js serializes everything to strings when using `process.send()`,
* so we need smart deserialization that will recreate log date and level for further processing by log4js internals.
*/
function deserializeLoggingEvent(loggingEventString) {
var loggingEvent;
try {
loggingEvent = JSON.parse(loggingEventString);
loggingEvent.startTime = new Date(loggingEvent.startTime);
loggingEvent.level = log4js.levels.toLevel(loggingEvent.level.levelStr);
} catch (e) {
// JSON.parse failed, just log the contents probably a naughty.
loggingEvent = {
startTime: new Date(),
categoryName: 'log4js',
level: log4js.levels.ERROR,
data: [ 'Unable to parse log:', loggingEventString ]
};
}
return loggingEvent;
}
/**
* Creates an appender.
*
* If the current process is a master (`cluster.isMaster`), then this will be a "master appender".
* Otherwise this will be a worker appender, that just sends loggingEvents to the master process.
*
* If you are using this method directly, make sure to provide it with `config.actualAppenders` array
* of actual appender instances.
*
* Or better use `configure(config, options)`
*/
function createAppender(config) {
if (cluster.isMaster) {
var masterAppender = function(loggingEvent) {
if (config.actualAppenders) {
var size = config.actualAppenders.length;
for(var i = 0; i < size; i++) {
if (!config.appenders[i].category || config.appenders[i].category === loggingEvent.categoryName) {
// Relying on the index is not a good practice but otherwise the change would have been bigger.
config.actualAppenders[i](loggingEvent);
}
}
}
}
// Listen on new workers
cluster.on('fork', function(worker) {
worker.on('message', function(message) {
if (message.type && message.type === '::log-message') {
// console.log("master : " + cluster.isMaster + " received message: " + JSON.stringify(message.event));
var loggingEvent = deserializeLoggingEvent(message.event);
masterAppender(loggingEvent);
}
});
});
return masterAppender;
} else {
return function(loggingEvent) {
// If inside the worker process, then send the logger event to master.
if (cluster.isWorker) {
// console.log("worker " + cluster.worker.id + " is sending message");
process.send({ type: '::log-message', event: serializeLoggingEvent(loggingEvent)});
}
}
}
}
function configure(config, options) {
if (config.appenders && cluster.isMaster) {
var size = config.appenders.length;
config.actualAppenders = new Array(size);
for(var i = 0; i < size; i++) {
log4js.loadAppender(config.appenders[i].type);
config.actualAppenders[i] = log4js.appenderMakers[config.appenders[i].type](config.appenders[i], options);
}
}
return createAppender(config);
}
exports.appender = createAppender;
exports.configure = configure;