embark-area-51/lib/utils/logHandler.js

72 lines
2.1 KiB
JavaScript

const utils = require('./utils');
// define max number of logs to keep in memory for this process
// to prevent runaway memory leak
const MAX_LOGS = require('../constants').logs.maxLogLength;
class LogHandler {
constructor({events, logger, processName, silent}) {
this.events = events;
this.logger = logger;
this.processName = processName;
this.silent = silent;
this.logs = [];
this.removedCount = 0;
}
/**
* Servers as an interception of logs, normalises the message output and
* adds metadata (timestamp, id) the data,
* stores the log in memory, then sends it to the logger for output. Max
* number of logs stored in memory is capped by MAX_LOGS
* @param {Object} msg Object containing the log message (msg.message)
*
* @returns {void}
*/
handleLog(msg) {
if(!msg) return;
// Sometimes messages come in with line breaks, so we need to break them up accordingly.
let processedMessages = [];
// Ensure that `msg.message` is an array, so we process this consistently. Sometimes it
// is an Array, sometimes it is a string.
if(typeof msg.message === 'string') {
processedMessages = [msg.message];
} else {
msg.message.forEach(message => {
let lines = message.split("\n");
lines.forEach(line => processedMessages.push(line));
});
}
const timestamp = new Date().getTime();
processedMessages.forEach((message) => {
const log = {
msg: message,
msg_clear: message.stripColors,
logLevel: msg.logLevel,
name: this.processName,
timestamp
};
if(this.logs.length >= MAX_LOGS){
this.logs.shift();
this.removedCount++;
}
const id = this.logs.push(log) - 1 + this.removedCount;
this.events.emit(`process-log-${this.processName}`, id, log);
if (this.silent && msg.type !== 'error') {
return;
}
if (this.logger[msg.type]) {
return this.logger[msg.type](utils.normalizeInput(message));
}
this.logger.debug(utils.normalizeInput(message));
});
}
}
module.exports = LogHandler;