Class: Karafka::Swarm::LivenessListener

Inherits:
Object
  • Object
show all
Includes:
Core::Helpers::Time
Defined in:
lib/karafka/swarm/liveness_listener.rb

Overview

Simple listener for swarm nodes that:

- reports once in a while to make sure that supervisor is aware we do not hang
- makes sure we did not become an orphan and if so, exits

Direct Known Subclasses

Pro::Swarm::LivenessListener

Instance Method Summary collapse

Constructor Details

#initialize ⇒ LivenessListener

Initializes the liveness listener



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# File 'lib/karafka/swarm/liveness_listener.rb', line 17

def initialize
  @last_checked_at = 0
  @mutex = Mutex.new
end

Instance Method Details

#on_client_events_poll(_event) ⇒ Object

Report from events poll so liveness works during long processing. This event fires periodically during wait even when the listener is blocked on consumer jobs, preventing the supervisor from killing the node.

Parameters:

  • _event (Karafka::Core::Monitoring::Event) 


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# File 'lib/karafka/swarm/liveness_listener.rb', line 39

def on_client_events_poll(_event)
  report_liveness
end

#on_connection_listener_before_fetch_loop(_event) ⇒ Object

Report liveness before the first fetch loop iteration so the supervisor gets an initial healthy report even if the first consumption takes longer than the report timeout.

Parameters:

  • _event (Karafka::Core::Monitoring::Event) 


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# File 'lib/karafka/swarm/liveness_listener.rb', line 25

def on_connection_listener_before_fetch_loop(_event)
  report_liveness
end

#on_connection_listener_fetch_loop(_event) ⇒ Object

Report from the fetch loop at the top of each iteration

Parameters:

  • _event (Karafka::Core::Monitoring::Event) 


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# File 'lib/karafka/swarm/liveness_listener.rb', line 31

def on_connection_listener_fetch_loop(_event)
  report_liveness
end