`class Queue`

Immutable policy for one class of requests.

Nested Classes and Modules

class Builder: Builds a queue policy using the configuration DSL.

Definitions

`def initialize(name, matcher:, eligibility:, admission:, balance_policy:, depth_limit:, wait_limit:, shed_status:, shed_headers:)`

Signature

parameter　name　Symbol | String: The stable queue name.
parameter　matcher　Proc | Nil: The request classifier.
parameter　eligibility　Proc | Nil: The backend eligibility policy.
parameter　admission　#admit? | #call | Nil: The queue admission policy.
parameter　balance_policy　#select: The backend balance policy.
parameter　depth_limit　Integer | Nil: The maximum queue depth.
parameter　wait_limit　Float | Nil: The maximum queue wait.
parameter　shed_status　Integer: The rejection response status.
parameter　shed_headers　Hash: The rejection response headers.

Implementation

def initialize(name, matcher:, eligibility:, admission:, balance_policy:, depth_limit:, wait_limit:, shed_status:, shed_headers:)
	@name = name.to_sym
	@matcher = matcher
	@eligibility = eligibility
	@admission = admission
	@balance_policy = balance_policy
	@depth_limit = depth_limit
	@wait_limit = wait_limit
	@shed_status = shed_status
	@shed_headers = shed_headers
end

`def match?(request)`

Signature

parameter　request　Protocol::HTTP::Request: The request to classify.
returns　Boolean | Nil: Whether the request matches this queue.

Implementation

def match?(request)
	@matcher&.call(request)
end

`def eligible?(backend, request)`

Signature

returns　Boolean: Whether a backend may serve the request.

Implementation

def eligible?(backend, request)
	!@eligibility || @eligibility.call(backend, request)
end

`def admit?(request, pending:)`

Signature

returns　Boolean: Whether a request may enter the pending queue.

Implementation

def admit?(request, pending:)
	return true unless @admission
	
	if @admission.respond_to?(:admit?)
		@admission.admit?(request, queue: self, pending: pending)
	else
		@admission.call(request, queue: self, pending: pending)
	end
end