Class: Cassandra::Tasks::SeedRegistry

Inherits:
Object
  • Object
show all
Defined in:
lib/cassandra/tasks/seedregistry.rb

Instance Method Summary collapse

Constructor Details

#initialize(cluster_name) ⇒ SeedRegistry

Create a new SeedRegistry task

Parameters:

  • cluster_name (String) —

    unique name (in Consul) for the Cassandra cluster

Raises:

  • (ArgumentError) 


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# File 'lib/cassandra/tasks/seedregistry.rb', line 13

def initialize cluster_name
  @cluster_name = cluster_name.to_s
  raise ArgumentError.new('cluster_name must not be empty') if @cluster_name.empty?
  @semaphore = nil
  @renew_thread = nil
  @nodetool_info_cache = nil
end

Instance Method Details

#can_seed? ⇒ Boolean

Return true if the Cassandra node is a valid seed, false otherwise

Returns:

  • (Boolean) 


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# File 'lib/cassandra/tasks/seedregistry.rb', line 42

def can_seed?
  return false unless state == :normal

  results = (nodetool_info_cached || '').split("\n")
  results.map! { |line| line.strip }

  filter_results = lambda do |key|
    potential = results.select { |line| line.include? key }
    potential.map! { |line| line.split(':')[1] }
    potential.compact!
    potential.size == 1 && potential.first.strip == 'true'
  end

  return false unless filter_results.call('Gossip active')
  return false unless filter_results.call('Thrift active')
  return false unless filter_results.call('Native Transport active')

  true
end

#data_center ⇒ String?

Return the data center the Cassandra node is in

The returned data center is reported by “nodetool info”.

Returns:

  • (String, nil) 


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# File 'lib/cassandra/tasks/seedregistry.rb', line 84

def data_center
  results = (nodetool_info_cached || '').split("\n")
  results.map! { |line| line.strip }
  results.select! { |line| line.include?('Data Center') }
  results.map! { |line| line.split(':')[1] }
  results.compact!
  return nil if results.size != 1
  results.first.strip
end

#rack ⇒ String?

Return the rack the Cassandra node is in

The returned rack is reported by “nodetool info”.

Returns:

  • (String, nil) 


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# File 'lib/cassandra/tasks/seedregistry.rb', line 100

def rack
  results = (nodetool_info_cached || '').split("\n")
  results.map! { |line| line.strip }
  results.select! { |line| line.include?('Rack') }
  results.map! { |line| line.split(':')[1] }
  results.compact!
  return nil if results.size != 1
  results.first.strip
end

#run! ⇒ Object

Get a lock in Consul registering the Cassandra node as a seed



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# File 'lib/cassandra/tasks/seedregistry.rb', line 29

def run!
  @nodetool_info_cache = nil
  if can_seed?
    try_get_seed_lock
  else
    release_seed_lock
  end
end

#schedule ⇒ Object

Schedule the seed registration process to run periodically



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# File 'lib/cassandra/tasks/seedregistry.rb', line 23

def schedule
  [:interval, '10s']
end

#state ⇒ state?

Return the state of the Cassandra node

The returned state is reported by “nodetool netstats”.

Returns:



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# File 'lib/cassandra/tasks/seedregistry.rb', line 68

def state
  results = (nodetool_netstats || '').split("\n")
  results.map! { |line| line.strip }
  results.select! { |line| line.include? 'Mode:' }
  results.map! { |line| line.split(':')[1] }
  results.compact!
  return nil if results.size != 1
  results.first.strip.downcase.to_sym
end