Implementação do log estruturado

logger.js

'use strict';
const SimpleNodeLogger = require('simple-node-logger');
const loggerConstants = require('./logger.constants');
const opts = {
timestampFormat: loggerConstants.emptyFormat,
level: loggerConstants.logLevel
};
const AbstractAppender = SimpleNodeLogger.AbstractAppender,

manager = new SimpleNodeLogger(opts);
const JSONAppender = function (options = {}) {
  const appender = this, opts = {
    typeName: 'JSONAppender'
  };

  AbstractAppender.extend(this, opts);
  this.write = function (entry) {
    var fields = appender.formatEntry(entry);
    fields[1] = entry.level;
    process.stdout.write(JSON.stringify({
      level: fields[1],
      message: fields[2],
      timestamp: new Date().toJSON()
    }) + '\n');
  };
};
manager.addAppender(new JSONAppender());
const log = manager.createLogger();
module.exports = log;