discourse/spec/components/scheduler/defer_spec.rb

# encoding: utf-8
# frozen_string_literal: true

require 'rails_helper'

describe Scheduler::Defer do
  class DeferInstance
    include Scheduler::Deferrable
  end

  def wait_for(timeout, &blk)
    till = Time.now + (timeout.to_f / 1000)
    while Time.now < till && !blk.call
      sleep 0.001
    end
  end

  class TrackingLogger < ::Logger
    attr_reader :messages
    def initialize
      super(nil)
      @messages = []
    end
    def add(*args, &block)
      @messages << args
    end
  end

  def track_log_messages
    old_logger = Rails.logger
    logger = Rails.logger = TrackingLogger.new
    yield logger.messages
    logger.messages
  ensure
    Rails.logger = old_logger
  end

  before do
    @defer = DeferInstance.new
    @defer.async = true
  end

  after do
    @defer.stop!
  end

  it "supports timeout reporting" do
    @defer.timeout = 0.05

    m = track_log_messages do |messages|
      10.times do
        @defer.later("fast job") {}
      end
      @defer.later "weird slow job" do
        sleep
      end

      wait_for(200) do
        messages.length == 1
      end
    end

    expect(m.length).to eq(1)
    expect(m[0][2]).to include("weird slow job")
  end

  it "can pause and resume" do
    x = 1
    @defer.pause

    @defer.later do
      x = 2
    end

    expect(@defer.length).to eq(1)

    @defer.do_all_work

    expect(x).to eq(2)

    @defer.resume

    @defer.later do
      x = 3
    end

    wait_for(1000) do
      x == 3
    end

    expect(x).to eq(3)
  end

  it "recovers from a crash / fork" do
    s = nil
    @defer.stop!
    wait_for(10) do
      @defer.stopped?
    end
    # hack allow thread to die
    sleep 0.005

    @defer.later do
      s = "good"
    end

    wait_for(10) do
      s == "good"
    end

    expect(s).to eq("good")
  end

  it "can queue jobs properly" do
    s = nil

    @defer.later do
      s = "good"
    end

    wait_for(10) do
      s == "good"
    end

    expect(s).to eq("good")
  end

end