Class: Deadpool::FailoverProtocol::Base

Inherits:
Object
  • Object
show all
Defined in:
lib/deadpool/failover_protocol.rb

Direct Known Subclasses

EtcHosts, ExecRemoteCommand

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(config, failover_config, logger) ⇒ Base

Returns a new instance of Base.



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# File 'lib/deadpool/failover_protocol.rb', line 13

def initialize(config, failover_config, logger)
  @name            = failover_config[:name].nil? ? '' : failover_config[:name]
  @state           = Deadpool::State.new @name, self.class
  @config          = config
  @logger          = logger
  @primary_host    = @config[:primary_host]
  @secondary_host  = @config[:secondary_host]
  @failover_config = failover_config
  setup
end

Instance Attribute Details

#config ⇒ Object (readonly)

Returns the value of attribute config.



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# File 'lib/deadpool/failover_protocol.rb', line 11

def config
  @config
end

#logger ⇒ Object

Returns the value of attribute logger.



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# File 'lib/deadpool/failover_protocol.rb', line 10

def logger
  @logger
end

Instance Method Details

#initiate_failover_protocol! ⇒ Object

Overwrite this if you need to. Update state to reflect that failover has been initiated. State must be updated to no less than WARNING. State must be CRITICAL if any step of the protocol fails. Lock the state at whatever stage the failover reached. return true or false on success or failure.



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# File 'lib/deadpool/failover_protocol.rb', line 35

def initiate_failover_protocol!
  logger.info "Performing Preflight Check"
  @state.set_state WARNING, "Failover Protocol Initiated."

  if preflight_check
    logger.info "Preflight Check Passed."
    @state.add_message "Preflight Check Passed."
  else
    logger.error "Preflight Check Failed!  Aborting Failover Protocol."
    @state.escalate_status_code CRITICAL
    @state.add_error_message "Preflight Check Failed! Failover Protocol Aborted!"
    @state.lock
    return false
  end

  if promote_to_primary(@secondary_host)
    logger.info "#{@secondary_host} successfully promoted to primary"
    @state.add_message "Failover Protocol Successful."
    @state.lock
    return true
  else
    logger.info "#{@secondary_host} promotion failed."
    @state.escalate_status_code CRITICAL
    @state.add_error_message "Failover Protocol Failed!"
    @state.lock
    return false
  end
end

#preflight_check ⇒ Object

Return true or false Don’t update system state. return true or false success or failure



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# File 'lib/deadpool/failover_protocol.rb', line 67

def preflight_check
  return false
end

#promote_to_primary(new_primary) ⇒ Object

Promote the host to primary. This is used by initiate_failover_protocol! and for manual promotion by an administrator. new_primary is an IP address TODO: change new_primary to be a config label. return true or false success or failure



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# File 'lib/deadpool/failover_protocol.rb', line 76

def promote_to_primary(new_primary)
  return false
end

#setup ⇒ Object

Implementation specific initialization should be placed here.



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# File 'lib/deadpool/failover_protocol.rb', line 25

def setup
end

#system_check ⇒ Object

Perform checks against anything that could cause a failover protocol to fail Perform checks on system state. return New Deadpool::StateSnapshot



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# File 'lib/deadpool/failover_protocol.rb', line 83

def system_check
  return Deadpool::StateSnapshot.new @state
end