kami-parse-server/src/Adapters/Logger/WinstonLogger.js

import winston from 'winston';
import fs from 'fs';
import path from 'path';
import DailyRotateFile from 'winston-daily-rotate-file';
import _ from 'lodash';
import defaults from '../../defaults';

const logger = new winston.Logger();
const additionalTransports = [];

function updateTransports(options) {
  const transports = Object.assign({}, logger.transports);
  if (options) {
    const silent = options.silent;
    delete options.silent;
    if (_.isNull(options.dirname)) {
      delete transports['parse-server'];
      delete transports['parse-server-error'];
    } else if (!_.isUndefined(options.dirname)) {
      transports['parse-server'] = new DailyRotateFile(
        Object.assign(
          {},
          {
            filename: 'parse-server.info',
            name: 'parse-server',
          },
          options,
          { timestamp: true }
        )
      );
      transports['parse-server-error'] = new DailyRotateFile(
        Object.assign(
          {},
          {
            filename: 'parse-server.err',
            name: 'parse-server-error',
          },
          options,
          { level: 'error', timestamp: true }
        )
      );
    }

    transports.console = new winston.transports.Console(
      Object.assign(
        {
          colorize: true,
          name: 'console',
          silent,
        },
        options
      )
    );
  }
  // Mount the additional transports
  additionalTransports.forEach(transport => {
    transports[transport.name] = transport;
  });
  logger.configure({
    transports: _.values(transports),
  });
}

export function configureLogger({
  logsFolder = defaults.logsFolder,
  jsonLogs = defaults.jsonLogs,
  logLevel = winston.level,
  verbose = defaults.verbose,
  silent = defaults.silent,
} = {}) {
  if (verbose) {
    logLevel = 'verbose';
  }

  winston.level = logLevel;
  const options = {};

  if (logsFolder) {
    if (!path.isAbsolute(logsFolder)) {
      logsFolder = path.resolve(process.cwd(), logsFolder);
    }
    try {
      fs.mkdirSync(logsFolder);
    } catch (e) {
      /* */
    }
  }
  options.dirname = logsFolder;
  options.level = logLevel;
  options.silent = silent;

  if (jsonLogs) {
    options.json = true;
    options.stringify = true;
  }
  updateTransports(options);
}

export function addTransport(transport) {
  additionalTransports.push(transport);
  updateTransports();
}

export function removeTransport(transport) {
  const transportName =
    typeof transport == 'string' ? transport : transport.name;
  const transports = Object.assign({}, logger.transports);
  delete transports[transportName];
  logger.configure({
    transports: _.values(transports),
  });
  _.remove(additionalTransports, transport => {
    return transport.name === transportName;
  });
}

export { logger };
export default logger;