Class: LogStash::Inputs::Exec

Inherits:
Base
  • Object
show all
Includes:
PluginMixins::Scheduler
Defined in:
lib/logstash/inputs/exec.rb

Overview

Periodically run a shell command and capture the whole output as an event.

Notes:

  • The ‘command` field of this event will be the command run.

  • The ‘message` field of this event will be the entire stdout of the command.

Instance Method Summary collapse

Instance Method Details

#execute(queue) ⇒ Object

Execute a given command

Parameters:

  • queue —

    the LS queue to append events to



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# File 'lib/logstash/inputs/exec.rb', line 73

def execute(queue)
  start = Time.now
  output = exit_status = nil
  begin
    @logger.debug? && @logger.debug("Running exec", :command => @command)
    output, exit_status = run_command()
  rescue StandardError => e
    @logger.error("Error while running command",
      :command => @command, :exception => e, :backtrace => e.backtrace)
  rescue Exception => e
    @logger.error("Exception while running command",
      :command => @command, :exception => e, :backtrace => e.backtrace)
  end
  duration = Time.now.to_r - start.to_r
  @logger.debug? && @logger.debug("Command completed", :command => @command, :duration => duration.to_f)
  if output
    @codec.decode(output) do |event|
      decorate(event)
      event.set(@host_name_field, @hostname) unless event.include?(@host_name_field)
      event.set(@process_command_line_field, @command) unless event.include?(@process_command_line_field)
      event.set(@process_exit_code_field, exit_status) unless event.include?(@process_exit_code_field)
      event.set(@process_elapsed_time_field, to_nanos(duration)) if @process_elapsed_time_field
      event.set(@legacy_duration_field, duration.to_f) if @legacy_duration_field
      queue << event
    end
  end
  duration
end

#register ⇒ Object 



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# File 'lib/logstash/inputs/exec.rb', line 39

def register
  @hostname = Socket.gethostname.freeze

  if (@interval.nil? && @schedule.nil?) || (@interval && @schedule)
    raise LogStash::ConfigurationError, "exec input: either 'interval' or 'schedule' option must be defined."
  end

  @host_name_field =            ecs_select[disabled: 'host',                     v1: '[host][name]']
  @process_command_line_field = ecs_select[disabled: 'command',                  v1: '[process][command_line]']
  @process_exit_code_field =    ecs_select[disabled: '[@metadata][exit_status]', v1: '[process][exit_code]']
  
  # migrate elapsed time tracking to whole nanos, from legacy floating-point fractional seconds
  @process_elapsed_time_field = ecs_select[disabled: nil,                        v1: '[@metadata][input][exec][process][elapsed_time]'] # in nanos
  @legacy_duration_field =      ecs_select[disabled: '[@metadata][duration]',    v1: nil] # in seconds
end

#run(queue) ⇒ Object

def register



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# File 'lib/logstash/inputs/exec.rb', line 55

def run(queue)
  if @schedule
    scheduler.cron(@schedule) { execute(queue) }
    scheduler.join
  else
    while !stop?
      duration = execute(queue)
      wait_until_end_of_interval(duration)
    end # loop
  end
end

#stop ⇒ Object

def run



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# File 'lib/logstash/inputs/exec.rb', line 67

def stop
  close_out_and_in
end