Class: Async::GRPC::XDS::HealthChecker

Inherits:
Object
  • Object
show all
Defined in:
lib/async/grpc/xds/health_checker.rb

Overview

Performs health checks on endpoints. Called by LoadBalancer’s loop. Runs within the caller’s reactor; does not spawn tasks or reactors. Only HTTP health checks are supported; gRPC health checks return :unknown.

Instance Method Summary collapse

Constructor Details

#initialize(health_checks) ⇒ HealthChecker

Initialize health checker



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# File 'lib/async/grpc/xds/health_checker.rb', line 20

def initialize(health_checks)
	@health_checks = health_checks
	@endpoints = []
	@cache = {}
end

Instance Method Details

#check(endpoint) ⇒ Object

Check health of endpoint. Runs in caller’s reactor.



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# File 'lib/async/grpc/xds/health_checker.rb', line 37

def check(endpoint)
	if cached = @cache[endpoint]
		return cached[:status] if Time.now - cached[:time] < 5
	end
	
	status = perform_check(endpoint)
	@cache[endpoint] = {status: status, time: Time.now}
	status
end

#close ⇒ Object

Close health checker



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# File 'lib/async/grpc/xds/health_checker.rb', line 48

def close
	@cache.clear
end

#update_endpoints(endpoints) ⇒ Object

Update endpoints (cleans cache for removed endpoints)



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# File 'lib/async/grpc/xds/health_checker.rb', line 28

def update_endpoints(endpoints)
	removed = @endpoints - endpoints
	removed.each{|endpoint| @cache.delete(endpoint)}
	@endpoints = endpoints
end