log-segment

log-segment

javascript logger with partition

Purpose

Quickly manage logs by two level and segment.

Install

$ npm i log-segment --save

Quick start

log-segment is singleton, so just require and use everywhere.

const log = require('log-segment')

const sql = 'INSERT INTO users (username, name) VALUES ($1, $2)'
log.info('sql', 'create user', log.value('sql', sql), log.chrono('insert-user'))
db.query(sql)
.then(() => {
  log.success('sql', 'user created.', log.value('sql', sql), log.chrono('insert-user'))
})
.catch((err) => {
  log.error('sql', 'user not created', log.value('sql', sql), log.value('error', err), log.chrono('insert-user'))
})

const log = require('log-segment')

require('express')().all('/*', (request, response) => {
  log.info('http', 'request', request.method, request.baseUrl)
  
  doSomething(request)
  .then((output) => {
    response.send(output)
    log.success('http', 'response on request', request.method, request.baseUrl)
  })
  .catch((err) => {
    response.sendStatus(500)
    log.error('http', 'response on request', request.method, request.baseUrl, log.value('err', err))
  })
})

Default settings

Default settings provide any levels and segments enabled to console output.
Default levels are: info, success, warning, error, panic.
There is no hierarchy by levels.

{ 
  levels: {
     '*': { color: 'white' },
     info: { color: 'blue', marker: 'ℹ️' },
     success: { color: 'green', marker: '✔' },
     warning: { color: 'yellow', marker: '❗️️' },
     error: { color: 'red', marker: '✗️' },
     panic: { color: 'magenta', marker: '😱' }
  },
  segments: { '*': { color: 'white' } },
  format: '{segment} | {marker} [{timestamp}] {message}',
  enabled: { segments: '*', levels: '*' } 
}

Custom segments

const log = require('log-segment')

log.set({
  segments: {
    http: {
      color: 'cyan'
    },
    html: {
      color: 'magenta'
    },
    sql: {
      mode: log.mode.FILE,
      file: '/tmp/myapp/sql.log'
    },
    sys: {
      mode: log.mode.FILE,
      file: '/tmp/myapp/sys.log',
      format: '{timestamp} {message}'
    },
  }
})

const sql = 'INSERT INTO table ...'

log.info('sql', 'executing query ...', log.value('sql', sql))
log.success('sql', 'query done.', log.value('sql', sql))

const request = {
  method: 'GET',
  baseUrl: '/it/4x/api.html#req'
}

const err = new Error('file not found')

log.info('http', 'request', request.method, request.baseUrl)
log.error('http', 'response on request', request.method, request.baseUrl, log.value('err', err))

let username = null
log.warning('html', 'rendering missing value', log.value('username', username))

Custom levels

const log = require('log-segment')

log.set({
  levels: {
    trace: {
      marker: '[TRACE]'
    },
    warning: {
      marker: '[WARN]'
    },
    error: {
      marker: '[ERR]',
      mode: log.mode.FILE,
      file: '/tmp/myapp/error.log',
      format: '{timestamp} {message}'
    }
  }
})

const sql = 'INSERT INTO table ...'

log.trace('sql', 'executing query ...', log.value('sql', sql))
log.trace('sql', 'query done.', log.value('sql', sql))

const request = {
  method: 'GET',
  baseUrl: '/it/4x/api.html#req'
}

const err = new Error('file not found')

log.trace('http', 'request', request.method, request.baseUrl)
log.error('http', 'response on request', request.method, request.baseUrl, log.value('err', err))

let username = null
log.warning('html', 'rendering missing value', log.value('username', username))

Custom format

Default format is '{segment} | {marker} [{timestamp}] {message}'.
You can optionally add {trace} to format and it will implicitly add trace information

log.set({
  format: '{marker} [{timestamp}] {message} {trace}'
})

Use Cases

log.set({
  segments: {
    http: { color: 'cyan' },
    network: { color: 'blue' },
    db: { color: 'yellow' },
    sql: { }
  }
})

Development

Just enable everything on console

log.set({ enabled: { segments: '*', levels: '*' } })

Debug

Enable only segments to focus on, at any levels, to find that bug

log.set({ enabled: { segments: ['sql', 'network'] } })

Beta

Enable all segments, disable info and success level

log.set({ disabled: { levels: ['info', 'success'] } })

Production

Different behaviour for each level:

• disable not interesting parts: success level
• different file for each type: info, warning, error and remove marks
• separate sql file
• on panic send email

log.set({
  enabled: {
    segments: ['sql'],
    levels: ['info', 'warning', 'error', 'panic']
  },
  segments: {
      sql: {
        mode: log.mode.FILE,
        file: '/var/log/myapp/sql'
      }
  },
  levels: {
    info: {
      marker: '[i]',
      mode: log.mode.FILE,
      file: '/var/log/myapp/info'
    },
    warning: {
      marker: '[warn]',
      mode: log.mode.FILE,
      file: '/var/log/myapp/warn'
    },
    error: {
      marker: '[err]',
      mode: log.mode.FILE,
      file: '/var/log/myapp/error'
    },
    panic: {
      mode: log.mode.EMAIL,
        email: {
          transporter: {
            service: 'gmail',
            auth: {
              user: '***@gmail.com',
              pass: '***'
            }
          }
        }
        options: {
          from: '"log-segment" <[e-mail]>',
          to: '[e-mail]',
          subject: 'myapp PANIC'
        }
      }
    }
  }
})

Documentation

See documentation for further informations.

Changelog

v. 1.7.0

• Add custom format to level, optionally add {segment}
• Default format review as '{segment} | {marker} [{timestamp}] {message}'

v. 1.6.0

• Add chrono function log.chrono('tag')

v. 1.3.0

• Add customizable output default format
• Add message info trace, timestamp

v. 1.2.0

• Add .check() to check settings for
  • console > color
  • files > write permission
  • emails > sending settings

v. 1.1.0

• Add support for email mode

TODO

• bdd test / tollo
• pre-commit
• travis ci
• browser support, only console mode (!colors) console.log('%c message', 'color: red');
• custom format in log.value
• custom mode: stream (sms, telegram and whatever)
• multiple mode for each setting (example: on panic send email + log to file + send sms + call mom)
• (evaluate) support workers (as transport)
  • bunyan
  • pino
  • winston
  • debug
  • log
  • npmlog
  • others?

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License

The MIT License (MIT)

Copyright (c) 2017-2018, braces lab

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.