winston-logzio/lib/winston-logzio.js

const Transport = require('winston-transport');
const stringifySafe = require('json-stringify-safe');
const logzioNodejs = require('logzio-nodejs');
const {
  LEVEL,
  MESSAGE,
} = require('triple-beam');

module.exports = class LogzioWinstonTransport extends Transport {
  constructor(options) {
    super(options);
    this.name = options.name || 'LogzioLogger';
    this.level = options.level || 'info';
    this.logzioLogger = logzioNodejs.createLogger(options);
  }

  log(info, callback) {
    setImmediate(() => {
      this.emit('logged', info);
    });

    const infoMessage = info.message || info[MESSAGE];
    let msg;
    if (typeof infoMessage !== 'string' && typeof infoMessage !== 'object') {
      msg = {
        message: this.constructor.safeToString(infoMessage),
      };
    } else if (typeof infoMessage === 'string') {
      msg = {
        message: infoMessage,
      };
    }

    const logObject = Object.assign({},
      info,
      msg, {
        level: info[LEVEL] || this.level,
        name: this.name,
      });

    this.logzioLogger.log(logObject);
    callback(null, true);
  }

  static safeToString(json) {
    try {
      return JSON.stringify(json);
    } catch (ex) {
      return stringifySafe(json, null, null, () => {});
    }
  }

  finish(callback) {
    this.logzioLogger.sendAndClose(callback);
  }

  close(cb) {
    this.finish(() => {
      this.emit('finish');
      this.emit('close');
      if (cb) cb();
    });
  }
};