mysql-pause

= mysql-pause

== Description

mysql-pause is a proxy server to pause a query to MySQL.

== Source Code

https://bitbucket.org/winebarrel/mysql-pause

== Dependency

• EventMachine
• RExec

== Install

gem install mysql-pause

== Example === Start server

shell> mysql-pause start Starting daemon... Waiting for daemon to start... Daemon status: running pid=56921

shell> mysql -h 127.0.0.1 -P 13306 -u scott -ptiger mysql> select 1; +---+ | 1 | +---+ | 1 | +---+ 1 row in set (0.00 sec)

=== Pause

shell> mpctl pause

mysql> select 1; (...no response...)

=== Resume

shell> mpctl resume

(...resume response...) +---+ | 1 | +---+ | 1 | +---+ 1 row in set (18.01 sec)

== Extend MySQL adapter === Install

gem install mysql-pause-adapter-ext

=== Example code

require 'active_record' require 'mysql-pause/adapter-ext'

ActiveRecord::Base.establish_connection( :adapter => 'mysql2', :host => '127.0.0.1', :port => 13306, :username => 'scott', :password => 'tiger', :database => 'employees', :reconnect => true, )

class Employee < ActiveRecord::Base; end

loop do employee = Employee.new employee.first_name = 'Taro' employee.last_name = 'Yamada' employee.save! sleep 3 end

=== Behavior

log> DEBUG -- : (0.6ms) BEGIN log> DEBUG -- : SQL (0.7ms) INSERT INTO employees (first_name, last_name) VALUES ('Taro', 'Yamada') log> DEBUG -- : (0.8ms) COMMIT log> DEBUG -- : (0.6ms) BEGIN

shell> mpctl pause shell> service mysql restart shell> mpctl resume

log> DEBUG -- : (0.6ms) BEGIN (...handle error and reconnect...) log> DEBUG -- : Mysql2::Error: %MYSQL_PAUSE%;;1000;;Aborted backend connection: BEGIN log> WARN -- : ActiveRecord::StatementInvalid: Mysql2::Error: %MYSQL_PAUSE%;;1000;;Aborted backend connection: BEGIN log> DEBUG -- : (0.3ms) BEGIN log> DEBUG -- : SQL (2.1ms) INSERT INTO employees (first_name, last_name) VALUES ('Taro', 'Yamada') log> DEBUG -- : (0.8ms) COMMIT