Ruby mysql gem 'reconnect' object variable - mysql

Question

I am encountering the 'mysql has gone away' error in Ruby after a certain amount of time that the script has been running.
I want to try to tell the mysql gem to auto-reconnect when the connection is lost.
My current code looks like the following:
def self.connect()
begin
if !##dbh.nil?
self.disconnect
end
##dbh = Mysql.real_connect(##server, ##user, ##pass, ##db)
puts "[+] Connected to the " + ##db + " database with user '" + ##user + "'"
rescue Mysql::Error => e
# log error
end
end
The following guide [0] says that the mysql gem has a 'reconnect' object variable, however, I am unsure of how to use it within my code.
How do I implement this option into the code above?
Thanks in advance,
Ryan
[0] http://www.tmtm.org/en/mysql/ruby/
EDIT ---
OK. I think I have figured it out.
I need to add ##dbh.reconnect = true after the ##dbh = Mysql.real_connect(##server, ##user, ##pass, ##db) line.
Note: According to a 'nice' chapy on IRC the mysql gem may not be the best Ruby gem to use.

Answer 1

If you're starting on a new project, the mysql2 gem is the way to go. It's an enormous improvement over the old version.
An attempt to Ruby-ize your example is:
def connect
begin
if (#dbh)
self.disconnect
end
#dbh = Mysql.real_connect(#server, #user, #pass, #db)
puts "[+] Connected to the #{#db} database with user '#{#user}'"
rescue Mysql::Error => e
# log error
end
end
The reason for using traditional # variables is you can use attr_accessor if you design your interface properly.
It's better to use a singleton instance than to wreck around with a singleton class. For instance:
class MyApp
def self.db
#db ||= Database.new
end
class Database
# Instance methods like initialize, connect, disconnect, etc.
end
end
You can use this like:
MyApp.db.connect
The advantage of using an instance of a class instead of a class directly is you can support more than one connection at a time.