Class: FiberConnectionPool

Inherits:
Sequel::ConnectionPool
  • Object
show all
Defined in:
lib/stack-service-base/fiber_pool.rb

Constant Summary collapse

VALIDATION_TIMEOUT = 
20
POOL_SIZE = 
ENV.fetch('DB_CONNECTION_POOL_SIZE', '10').to_i

Instance Method Summary collapse

Constructor Details

#initialize(db, opts = OPTS) ⇒ FiberConnectionPool

Returns a new instance of FiberConnectionPool.



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# File 'lib/stack-service-base/fiber_pool.rb', line 25

def initialize(db, opts = OPTS)
  otl_span "FiberConnectionPool.initialize" do |span|
    super
    @allocator = ->() {
      make_new(:default).tap { |conn|
        $local_log["new connection (fiber pool) #{conn.__id__}"]
      }
    }
    @stock = []
    @acquired = {}
    @sp = Async::Semaphore.new opts[:max_connections] || POOL_SIZE
  end
end

Instance Method Details

#disconnect(symbol) ⇒ Object

def preconnect(_concurrent = false) = :unimplemented



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# File 'lib/stack-service-base/fiber_pool.rb', line 85

def disconnect(symbol)
  until @stock.empty?
    $local_log['disconnect connection (fiber pool)']
    @stock.shift.close
  end
end

#hold(_server = nil) ⇒ Object 



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# File 'lib/stack-service-base/fiber_pool.rb', line 48

def hold(_server = nil)
  return yield @acquired[Fiber.current] if @acquired[Fiber.current] # protect from recursion
  $local_log["hold in (fiber pool: #{__id__}) #{@stock.map{_1.__id__}}"]
  fiber = Fiber.current
  try_count = 2

  @sp.acquire do
    until @acquired[fiber] &&
      ( @acquired[fiber].instance_eval { @last_use_.nil? || (Time.now - @last_use_).to_i < VALIDATION_TIMEOUT } ||
        is_valid_connection?(@acquired[fiber]) )

      @acquired[fiber] = @stock.shift || @allocator.call
    end

    @acquired[fiber].instance_eval { @last_use_ = Time.now }
    yield @acquired[fiber]

  rescue Sequel::DatabaseDisconnectError => e
    $local_log["remove connection (fiber pool) retry(#{try_count})"]
    @acquired.delete(fiber)
    (try_count -=1) < 0 ? raise : retry

  rescue =>e
    $stdout.puts e.message
    $stdout.puts e.backtrace[0..10].join "\n"
    $local_log['remove connection (fiber pool) give up']
    @acquired.delete(fiber)
    raise
  ensure
    @stock.push @acquired.delete(fiber) if @acquired[fiber]
    $local_log["hold out (fiber pool: #{__id__}) #{@stock.map{_1.__id__}}"]
  end
end

#is_valid_connection?(conn) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/stack-service-base/fiber_pool.rb', line 39

def is_valid_connection?(conn)
  sql = valid_connection_sql
  log_connection_execute(conn, sql)
  true
rescue =>e_
  conn.close rescue nil
  false
end

#max_size ⇒ Object 



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# File 'lib/stack-service-base/fiber_pool.rb', line 83

def max_size = @sp.limit
# def preconnect(_concurrent = false) = :unimplemented

#pool_type ⇒ Object

def servers = []



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# File 'lib/stack-service-base/fiber_pool.rb', line 92

def pool_type = :fiber # :threaded

#size ⇒ Object 



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# File 'lib/stack-service-base/fiber_pool.rb', line 82

def size = @acquired.size

#sync ⇒ Object

:threaded



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# File 'lib/stack-service-base/fiber_pool.rb', line 93

def sync = yield