Class: ActiveRecord::Base

Inherits:
Object
  • Object
show all
Defined in:
lib/never_block/frameworks/activerecord.rb,
lib/active_record/connection_adapters/neverblock_postgresql_adapter.rb,
lib/active_record/connection_adapters/neverblock_mysql_adapter.rb

Overview

Patch ActiveRecord to store transaction depth information in fibers instead of threads. AR does not support nested transactions which makes the job easy. We also need to override the scoped methods to store the scope in the fiber context

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.decrement_open_transactions ⇒ Object

:nodoc:



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# File 'lib/never_block/frameworks/activerecord.rb', line 32

def self.decrement_open_transactions #:nodoc:
  Fiber.current['open_transactions'] -= 1
end

.increment_open_transactions ⇒ Object

:nodoc:



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# File 'lib/never_block/frameworks/activerecord.rb', line 26

def self.increment_open_transactions #:nodoc:
  open = Fiber.current['open_transactions'] ||= 0
  Fiber.current['start_db_transaction'] = open.zero?
  Fiber.current['open_transactions'] = open + 1
end

.neverblock_mysql_connection(config) ⇒ Object

Establishes a connection to the database that’s used by all Active Record objects



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# File 'lib/active_record/connection_adapters/neverblock_mysql_adapter.rb', line 63

def self.neverblock_mysql_connection(config) # :nodoc:
  config = config.symbolize_keys
  host     = config[:host]
  port     = config[:port]
  socket   = config[:socket]
  username = config[:username] ? config[:username].to_s : 'root'
  password = config[:password].to_s
  size     = config[:connections] || 4

  if config.has_key?(:database)
    database = config[:database]
  else
    raise ArgumentError, "No database specified. Missing argument: database."
  end
  MysqlCompat.define_all_hashes_method!
  ::ActiveRecord::ConnectionAdapters::NeverBlockMysqlAdapter.new(nil, logger, [size.to_i, host, username, password, database, port, socket, nil], config)
end

.neverblock_postgresql_connection(config) ⇒ Object

Establishes a connection to the database that’s used by all Active Record objects



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# File 'lib/active_record/connection_adapters/neverblock_postgresql_adapter.rb', line 75

def self.neverblock_postgresql_connection(config) # :nodoc:
  config = config.symbolize_keys
  host     = config[:host]
  port     = config[:port] || 5432
  username = config[:username].to_s
  password = config[:password].to_s
  size     = config[:connections] || 4

  if config.has_key?(:database)
    database = config[:database]
  else
    raise ArgumentError, "No database specified. Missing argument: database."
  end

  # The postgres drivers don't allow the creation of an unconnected PGconn object,
  # so just pass a nil connection object for the time being.
  ::ActiveRecord::ConnectionAdapters::NeverBlockPostgreSQLAdapter.new(nil, logger, [size, host, port, nil, nil, database, username, password], config)
end

.transaction(&block) ⇒ Object 



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# File 'lib/never_block/frameworks/activerecord.rb', line 15

def self.transaction(&block)
  increment_open_transactions
  begin
    connection.transaction(Fiber.current['start_db_transaction'], &block)
  ensure
    decrement_open_transactions
  end
end

Instance Method Details

#single_threaded_scoped_methods ⇒ Object

:nodoc:



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# File 'lib/never_block/frameworks/activerecord.rb', line 10

def single_threaded_scoped_methods #:nodoc:
  scoped_methods = (Fiber.current[:scoped_methods] ||= {})
  scoped_methods[self] ||= []
end