bunlogger

bunlogger

express logging middlewares built on bunyan and rotatelog-stream

Installation

$ npm install bunlogger --save

Features

1. app.use(logger.connect()) will populate the req.log, which is actually a child of the bunyan logger, simply req.log.info('...') will share the same cor_id in the access log and error log. cor_id is exposed on req.cor_id;

2. logging req.log.fatal(), req.log.error() into error log file. If error is sent to next(err) and req.log['fatal|error'] not got called, middleware app.use(logger.onError()) will log this error by error.status automatically. err.status == 4xx is warn level, err.status == 5xx is error level.

3. elapsed show the time spent in this req.

4. Integrate with rotatelog-stream for rotating logs to files.

5. See logging on the console in developing stage.

Quick Start

express

const express = require('express');
const AppLogger = require('bunlogger');
const logDir = require('path').join(__dirname, 'log');

   
var app = express();
app.log = new AppLogger({dev: true, logDir});

populate req.log and log all accesses

app.use(app.log.connect());

Catch express next(err) for logging, but skip if req.log got called above warn level.

app.use(app.log.onError());

log directory created and bunlogger.log, bunlogger-error.log created.

Finally, render req.cor_id in the final error handler, so the customer can contact you with cor_id for help.

Create logger

logger is using rotatelog-stream for rotating logs.

const Logger = require('..').Logger;
const join = require('path').join;

var log = new Logger({logDir: join(__dirname, 'log')});

log.info('hi info');
log.warn('hi warn');
log.error('hi error');

Print Error

A handy tool to replace console.error(err).

const printErr = require('bunlogger').printErr;

try {
  new NotExist();
} catch (er) {
  printErr(er)
}

cli

$ DEBUG=* node bin/www

Options

• name: {String},
• logDir: 'path/to/log/directory' - directory to save log files
• keep: {Number} - how many log files keep. See rotatelog-stream
• maxsize: {Number} - max filesize allowed. See rotatelog-stream
• dev: {Boolean} - Pipe logs to process.stdout for development, so we can see how logging file looks like in console.
• streams: {Array} - additional streams for Bunyan