Class: DbMon::Monitor

Inherits:
Object
  • Object
show all
Defined in:
lib/db_mon/monitor.rb

Direct Known Subclasses

MysqlMonitor, PgMonitor

Instance Method Summary collapse

Constructor Details

#initialize(options = {}) ⇒ Monitor

Returns a new instance of Monitor.



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# File 'lib/db_mon/monitor.rb', line 8

def initialize(options = {})
  @interval  = options['interval']     
  @threshold = options['threshold']
  @database  = options['database']
  @username  = options['username']
  @password  = options['password']
  @table     = options['table']
  @notify    = options['notify']
  @time_column = options['time_column'] || 'created_at'


  Mail.defaults do 
    delivery_method options['delivery_method'].to_sym
  end
end

Instance Method Details

#monitor_table ⇒ Object 



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# File 'lib/db_mon/monitor.rb', line 25

def monitor_table
  while true
    sleep @interval.to_i
    result = query_table 
    
    unless result.count >= @threshold
      send_alert_email
    end
  end
end

#query_table ⇒ Object 



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# File 'lib/db_mon/monitor.rb', line 36

def query_table
  raise "Must be implemented on child classes" 
end

#send_alert_email ⇒ Object 



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# File 'lib/db_mon/monitor.rb', line 40

def send_alert_email
  table     = @table
  database  = @database
  threshold = @threshold
  interval  = @interval
  notify    = @notify
  
  mail = Mail.deliver do 
    from '[email protected]'
    to notify
    subject 'Database Monitor Alert'

    html_part do
      content_type 'text/html; charset=UTF-8'
      body "        <h2>Database Alert</h2>\n\n        <p>\n          The \#{table} table on \#{database} has had less than \#{threshold} record(s) \n          added to it in the last \#{interval} seconds. This may be an indication that \n          there is a problem with the service(s) responsible for creating these records.\n        </p>\n        <p>\n         \#{interval} seconds is:\n        </p>\n        \#{interval/60.0} minutes<br />\n        \#{(interval/60.0)/60.0} hours<br />\n        \#{((interval/60.0)/60.0)/24.0} days<br />\n      EOM\n    end\n  end\n\n  p \n\nend\n"