log-segment

log-segment

Javascript logger with partition

Purpose

Why Another Log Module? Because not all logs are equal.
I'd like to use a pliable tool to quickly manage logs by two factors: level and segment.

Install

$ npm i log-segment

Quick start

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

const log = require('log-segment')

const sql = 'INSERT INTO table ...'
log.info('sql', 'executing query ...', log.value('sql', sql))
db.query(sql)
.then(() => {
  log.success('sql', 'query done.', log.value('sql', sql))
})
.catch((err) => {
  log.error('sql', 'query error', log.value('sql', sql))
})

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' } },
  template: '{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'
    }
  }
})

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({
  segments: {
    http: {
      color: 'yellow'
    },
    sql: {
      color: 'white'
    }
  },
  levels: {
    trace: {
      marker: '[TRACE]'
    },
    warning: {
      marker: '[WARN]'
    },
    error: {
      marker: '[ERR]'
    }
  }
})

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 '{marker} [{timestamp}] {message}'.
You can also add {trace}

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, template rendering
• 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.MAIL,
        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. 1.3.0

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

v. 1.2.0

• Add .check(): check settings for
  • console > color
  • files > write permission
  • emails > send settings

v. 1.1.0

• Add support for email mode

TODO

• add chrono > log.chrono('tag')
• custom format for each level (ex. add trace only in panic)
• browser support, only console mode (!colors) console.log('%c message', 'color: red');
• custom mode: stream, (sms, telegram and whatever)
• custom format in log.value
• multiple mode for each setting (example: on panic send email + log to file + send sms + call mom)
• (evaluate) support workers (as transport)
  • pino
  • npmlog
  • winston
  • log
  • debug
  • bunyan
  • others?

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License

The MIT License (MIT)

Copyright (c) 2017, 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.