discourse/lib/scheduler/defer.rb

147 lines
3.5 KiB
Ruby

# frozen_string_literal: true
require "weakref"
module Scheduler
module Deferrable
DEFAULT_TIMEOUT ||= 90
STATS_CACHE_SIZE ||= 100
def initialize
@async = !Rails.env.test?
@queue =
WorkQueue::ThreadSafeWrapper.new(
WorkQueue::FairQueue.new(:site, 500) do
WorkQueue::FairQueue.new(:user, 100) { WorkQueue::BoundedQueue.new(50) }
end,
)
@mutex = Mutex.new
@stats_mutex = Mutex.new
@paused = false
@thread = nil
@reactor = nil
@timeout = DEFAULT_TIMEOUT
@stats = LruRedux::ThreadSafeCache.new(STATS_CACHE_SIZE)
end
def timeout=(t)
@mutex.synchronize { @timeout = t }
end
def length
@queue.size
end
def stats
@stats_mutex.synchronize { @stats.to_a }
end
def pause
stop!
@paused = true
end
def resume
@paused = false
end
# for test and sidekiq
def async=(val)
@async = val
end
def later(
desc = nil,
db = RailsMultisite::ConnectionManagement.current_db,
force: true,
current_user: nil,
&blk
)
@stats_mutex.synchronize do
stats = (@stats[desc] ||= { queued: 0, finished: 0, duration: 0, errors: 0 })
stats[:queued] += 1
end
if @async
start_thread if !@thread&.alive? && !@paused
@queue.push({ site: db, user: current_user, db: db, job: blk, desc: desc }, force: force)
else
blk.call
end
end
def stop!
@thread.kill if @thread&.alive?
@thread = nil
@reactor&.stop
@reactor = nil
end
# test only
def stopped?
!@thread&.alive?
end
def do_all_work
do_work(non_block = true) while !@queue.empty?
end
private
def start_thread
@mutex.synchronize do
@reactor = MessageBus::TimerThread.new if !@reactor
@thread =
Thread.new do
@thread.abort_on_exception = true if Rails.env.test?
do_work while true
end if !@thread&.alive?
end
end
# using non_block to match Ruby #deq
def do_work(non_block = false)
db, job, desc = @queue.shift(block: !non_block).values_at(:db, :job, :desc)
start = Process.clock_gettime(Process::CLOCK_MONOTONIC)
db ||= RailsMultisite::ConnectionManagement::DEFAULT
RailsMultisite::ConnectionManagement.with_connection(db) do
begin
warning_job =
@reactor.queue(@timeout) do
Rails.logger.error "'#{desc}' is still running after #{@timeout} seconds on db #{db}, this process may need to be restarted!"
end if !non_block
job.call
rescue => ex
@stats_mutex.synchronize do
stats = @stats[desc]
stats[:errors] += 1 if stats
end
Discourse.handle_job_exception(ex, message: "Running deferred code '#{desc}'")
ensure
warning_job&.cancel
end
end
rescue => ex
Discourse.handle_job_exception(ex, message: "Processing deferred code queue")
ensure
ActiveRecord::Base.connection_handler.clear_active_connections!
if start
@stats_mutex.synchronize do
stats = @stats[desc]
if stats
stats[:finished] += 1
stats[:duration] += Process.clock_gettime(Process::CLOCK_MONOTONIC) - start
end
end
end
end
end
class Defer
extend Deferrable
initialize
end
end