SMTP Appender for log4js

Sends log events as emails. If you use this appender, you should also call log4js.shutdown when your application closes so that any remaining emails can be sent. Many of the configuration options below are passed through to nodemailer, so you should read their docs to get the most out of this appender.

npm install log4js
npm install @log4js-node/smtp

Configuration

• type - @log4js-node/smtp
• SMTP - object (optional, if not present will use transport field)
  • host - string (optional, defaults to localhost)
  • port - integer (optional, defaults to 25)
  • auth - object (optional) - authentication details
    • user - string
    • pass - string
• transport - object (optional, if not present will use SMTP) - see nodemailer docs for transport options
  • plugin - string (optional, defaults to smtp) - the nodemailer transport plugin to use
  • options - object - configuration for the transport plugin
• attachment - object (optional) - send logs as email attachment
  • enable - boolean (optional, defaults to false)
  • message - string (optional, defaults to See logs as attachment) - message to put in body of email
  • filename - string (optional, defaults to default.log) - attachment filename
• sendInterval - integer (optional, defaults to 0) - batch emails and send in one email every sendInterval seconds, if 0 then every log message will send an email.
• shutdownTimeout - integer (optional, defaults to 5) - time in seconds to wait for emails to be sent during shutdown
• recipients - string - email addresses to send the logs to
• subject - string (optional, defaults to message from first log event in batch) - subject for email
• sender - string (optional) - who the logs should be sent as
• html - boolean (optional, defaults to false) - send the email as HTML instead of plain text
• layout - object (optional, defaults to basicLayout) - see layouts
• cc - string (optional) - email addresses to send the carbon-copy logs to
• bcc - string (optional) - email addresses to send the blind-carbon-copy logs to

Example (default config)

log4js.configure({
  appenders: {
    'email': {
      type: '@log4js-node/smtp', recipients: 'dev.team@company.name'
    }
  },
  categories: { default: { appenders: [ 'email' ], level: 'error' } }
});

This configuration will send an email using the smtp server running on localhost:25, for every log event of level ERROR and above. The email will be sent to dev.team@company.name, the subject will be the message part of the log event, the body of the email will be log event formatted by the basic layout function.

Example (logs as attachments, batched)

log4js.configure({
  appenders: {
    'email': {
      type: '@log4js-node/smtp',
      recipients: 'dev.team@company.name',
      subject: 'Latest logs',
      sender: 'my.application@company.name',
      attachment: {
        enable: true,
        filename: 'latest.log',
        message: 'See the attachment for the latest logs'
      },
      sendInterval: 3600
    }
  },
  categories: { default: { appenders: ['email'], level: 'ERROR' } }
});

This configuration will send an email once every hour, with all the log events of level 'ERROR' and above as an attached file.

Example (custom SMTP host)

log4js.configure({
  appenders: {
    email: {
      type: '@log4js-node/smtp', SMTP: { host: 'smtp.company.name', port: 8025 }, recipients: 'dev.team@company.name'
    }
  },
  categories: { default: { appenders: ['email'], level: 'info' } }
});

This configuration can also be written as:

log4js.configure({
  appenders: {
    email: {
      type: '@log4js-node/smtp',
      transport: {
        plugin: 'smtp',
        options: {
          host: 'smtp.company.name',
          port: 8025
        }
      },
      recipients: 'dev.team@company.name'
    }
  },
  categories: {
    default: { appenders: ['email'], level: 'info' }
  }
});

A similar config can be used to specify a different transport plugin than smtp. See the nodemailer docs for more details.