import createLogger from '@xen-orchestra/log'

const log = createLogger('my-module')

log.debug('only useful for debugging')
log.info('this information is relevant to the user')
log.warn('something went wrong but did not prevent current action')
log.error('something went wrong')
log.fatal('service/app is going down')

// you can add contextual info
log.debug('new API request', {
  method: 'foo',
  params: [ 'bar', 'baz' ]
  user: 'qux'
})

// by convention, errors go into the `error` field
log.error('could not join server', {
  error,
  server: 'example.org',
})

Then, at application level, configure the logs are handled:

import { configure, catchGlobalErrors } from '@xen-orchestra/log/configure'
import transportConsole from '@xen-orchestra/log/transports/console'
import transportEmail from '@xen-orchestra/log/transports/email'

const transport = transportEmail({
  service: 'gmail',
  auth: {
    user: 'jane.smith@gmail.com',
    pass: 'H&NbECcpXF|pyXe#%ZEb'
  },
  from: 'jane.smith@gmail.com',
  to: [
    'jane.smith@gmail.com',
    'sam.doe@yahoo.com'
  ]
})

configure([
  {
    // if filter is a string, then it is pattern
    // (https://github.com/visionmedia/debug#wildcards) which is
    // matched against the namespace of the logs
    filter: process.env.DEBUG,

    transport: transportConsole()
  },
  {
    // only levels >= warn
    level: 'warn',

    transport
  }
])

// send all global errors (uncaught exceptions, warnings, unhandled rejections)
// to this transport
catchGlobalErrors(transport)

Transports

Console

import transportConsole from '@xen-orchestra/log/transports/console'

configure(transportConsole())

Email

Optional dependency:

> yarn add nodemailer pretty-format

Configuration:

import transportEmail from '@xen-orchestra/log/transports/email'

configure(transportEmail({
  service: 'gmail',
  auth: {
    user: 'jane.smith@gmail.com',
    pass: 'H&NbECcpXF|pyXe#%ZEb'
  },
  from: 'jane.smith@gmail.com',
  to: [
    'jane.smith@gmail.com',
    'sam.doe@yahoo.com'
  ]
}))

Syslog

Optional dependency:

> yarn add split-host syslog-client

Configuration:

import transportSyslog from '@xen-orchestra/log/transports/syslog'

// By default, log to udp://localhost:514
configure(transportSyslog())

// But TCP, a different host, or a different port can be used
configure(transportSyslog('tcp://syslog.company.lan'))

Development

# Install dependencies
> yarn

# Run the tests
> yarn test

# Continuously compile
> yarn dev

# Continuously run the tests
> yarn dev-test

# Build for production (automatically called by npm install)
> yarn build

Contributions

Contributions are very welcomed, either on the documentation or on the code.

You may:

report any issue you've encountered;
fork and create a pull request.

README.md

@xen-orchestra/log

Install

Usage