Class: SinatraHealthCheck::Checker

Inherits:
Object
  • Object
show all
Defined in:
lib/sinatra-health-check/checker.rb

Overview

The application health check. Create an instance and use .health to repond to your health check requests.

Constant Summary collapse

DEFAULT_OPTS = 
{
  :aggregator => SinatraHealthCheck::Status::StrictAggregator.new,
  :exit       => true,
  :health     => true,
  :logger     => nil,
  :signals    => %w[TERM INT],
  :systems    => {},
  :timeout    => 10,
  :wait       => 0,
}

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(opts = {}) ⇒ Checker

Create a health checker. Params: aggrgator: an aggregator for substatuus, default: StrictAggregator exit: call exit at the end of graceful_stop health: initial health state logger: a logger signals: array of signals to register a graceful stop handler systems: a hash of subsystems responding to .status timeout: timeout for graceful stop in seconds wait: wait before setting health to unhealthy



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# File 'lib/sinatra-health-check/checker.rb', line 31

def initialize(opts = {})
  @opts = DEFAULT_OPTS.merge(opts)
  @aggregator = SinatraHealthCheck::Status::OverwritingAggregator.new(@opts[:aggregator])
  @health = @opts[:health]
  @systems = @opts[:systems]
  trap(@opts[:signals])
end

Instance Attribute Details

#health ⇒ Object

Returns the value of attribute health.



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# File 'lib/sinatra-health-check/checker.rb', line 18

def health
  @health
end

#systems ⇒ Object (readonly)

Returns the value of attribute systems.



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# File 'lib/sinatra-health-check/checker.rb', line 19

def systems
  @systems
end

Instance Method Details

#graceful_stop ⇒ Object

Set application to unhealthy state and stop it after wating for ++@timeout++.



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# File 'lib/sinatra-health-check/checker.rb', line 40

def graceful_stop
  # set to unhealthy state
  unless @stopper
    # spawn a thread to stop application after a given time
    @stopper = Thread.new do
      if @opts[:wait] > 0
        logger.info "asked to stop application, waiting for #{@opts[:wait]}s before doing so" if logger
        sleep @opts[:wait]
      end
      logger.info "stopping application, waiting for #{@opts[:timeout]}s" if logger
      @health = false
      sleep @opts[:timeout]
      logger.info "exit application" if logger
      exit if @opts[:exit]
    end
  end
end

#healthy? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/sinatra-health-check/checker.rb', line 70

def healthy?
  status.level != :error
end

#join ⇒ Object

Waits for the stopping thread to finish



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# File 'lib/sinatra-health-check/checker.rb', line 59

def join
  @stopper.join if @stopper
end

#status ⇒ Object

Returns a Status object



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# File 'lib/sinatra-health-check/checker.rb', line 64

def status
  statuus = {}
  systems.each { |k,v| statuus[k] = v.status if v.respond_to?(:status) }
  @aggregator.aggregate(statuus, health ? nil : SinatraHealthCheck::Status.new(:error, 'app is unhealthy'))
end