Class: RocketJob::Server

Inherits:
Object
  • Object
show all
Includes:
Plugins::Document, Plugins::StateMachine, SemanticLogger::Loggable
Defined in:
lib/rocket_job/server.rb

Overview

Server

On startup a server instance will automatically register itself if not already present

Starting a server in the foreground:

- Using a Rails runner:
  bin/rocketjob

Starting a server in the background:

- Using a Rails runner:
  nohup bin/rocketjob --quiet 2>&1 1>output.log &

Stopping a server:

- Stop the server via the Web UI
- Send a regular kill signal to make it shutdown once all active work is complete
    kill <pid>
- Or, use the following Ruby code:
  server = RocketJob::Server.where(name: 'server name').first
  server.stop!

Sending the kill signal locally will result in starting the shutdown process
immediately. Via the UI or Ruby code the server can take up to 15 seconds
(the heartbeat interval) to start shutting down.

Constant Summary collapse

@@shutdown = 
false

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.counts_by_state ⇒ Object

Returns [Hash<String:Integer>] of the number of servers in each state. Note: If there are no servers in that particular state then the hash will not have a value for it.

Example servers in every state:

RocketJob::Server.counts_by_state
# => {
       :aborted => 1,
       :completed => 37,
       :failed => 1,
       :paused => 3,
       :queued => 4,
       :running => 1,
       :queued_now => 1,
       :scheduled => 3
     }

Example no servers active:

RocketJob::Server.counts_by_state
# => {}



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# File 'lib/rocket_job/server.rb', line 142

def self.counts_by_state
  counts = {}
  collection.aggregate([
    {
      '$group' => {
        _id:   '$state',
        count: {'$sum' => 1}
      }
    }
  ]
  ).each do |result|
    counts[result['_id'].to_sym] = result['count']
  end
  counts
end

.destroy_zombies ⇒ Object

Destroy’s all instances of zombie server and requeue any jobs still “running” on those servers



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# File 'lib/rocket_job/server.rb', line 97

def self.destroy_zombies
  count = 0
  each do |server|
    next unless server.zombie?
    logger.warn "Destroying zombie server #{server.name}, and requeueing its jobs"
    server.destroy
    count += 1
  end
  count
end

.pause_all ⇒ Object

Pause all running servers



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# File 'lib/rocket_job/server.rb', line 114

def self.pause_all
  running.each(&:pause!)
end

.resume_all ⇒ Object

Resume all paused servers



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# File 'lib/rocket_job/server.rb', line 119

def self.resume_all
  paused.each(&:resume!)
end

.run(attrs = {}) ⇒ Object

Run the server process Attributes supplied are passed to #new



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# File 'lib/rocket_job/server.rb', line 187

def self.run(attrs = {})
  Thread.current.name = 'rocketjob main'
  # Create Indexes on server startup
  Mongoid::Tasks::Database.create_indexes
  register_signal_handlers

  server = create!(attrs)
  server.send(:run)
ensure
  server.destroy if server
end

.shutdown! ⇒ Object

Set shutdown indicator for this server process



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# File 'lib/rocket_job/server.rb', line 166

def self.shutdown!
  @@shutdown.make_true
end

.shutdown? ⇒ Boolean

Returns [true|false] whether the shutdown indicator has been set for this server process

Returns:

  • (Boolean) 


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# File 'lib/rocket_job/server.rb', line 161

def self.shutdown?
  @@shutdown.value
end

.stop_all ⇒ Object

Stop all running, paused, or starting servers



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# File 'lib/rocket_job/server.rb', line 109

def self.stop_all
  where(:state.in => [:running, :paused, :starting]).each(&:stop!)
end

.zombies(missed = 4) ⇒ Object

Scope for all zombie servers



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# File 'lib/rocket_job/server.rb', line 205

def self.zombies(missed = 4)
  dead_seconds        = Config.instance.heartbeat_seconds * missed
  last_heartbeat_time = Time.now - dead_seconds
  where(
    :state.in => [:stopping, :running, :paused],
    '$or'     => [
      {"heartbeat.updated_at" => {'$exists' => false}},
      {"heartbeat.updated_at" => {'$lte' => last_heartbeat_time}}
    ]
  )
end

Instance Method Details

#shutdown? ⇒ Boolean

Returns [Boolean] whether the server is shutting down

Returns:

  • (Boolean) 


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# File 'lib/rocket_job/server.rb', line 200

def shutdown?
  self.class.shutdown? || !running?
end

#zombie?(missed = 4) ⇒ Boolean

Returns [true|false] if this server has missed at least the last 4 heartbeats

Possible causes for a server to miss its heartbeats:

  • The server process has died

  • The server process is “hanging”

  • The server is no longer able to communicate with the MongoDB Server

Returns:

  • (Boolean) 


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# File 'lib/rocket_job/server.rb', line 223

def zombie?(missed = 4)
  return false unless running? || stopping? || paused?
  return true if heartbeat.nil? || heartbeat.updated_at.nil?
  dead_seconds = Config.instance.heartbeat_seconds * missed
  (Time.now - heartbeat.updated_at) >= dead_seconds
end