Module: Redis::Objects::Locks::ClassMethods
- Defined in:
- lib/redis/objects/locks.rb
Overview
Class methods that appear in your class when you include Redis::Objects.
Instance Method Summary collapse
-
#clear_lock(name, id) ⇒ Object
Clear the lock.
-
#lock(name, options = {}) ⇒ Object
Define a new lock.
-
#obtain_lock(name, id, &block) ⇒ Object
Obtain a lock, and execute the block synchronously.
Instance Method Details
#clear_lock(name, id) ⇒ Object
Clear the lock. Use with care - usually only in an Admin page to clear stale locks (a stale lock should only happen if a server crashes.)
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# File 'lib/redis/objects/locks.rb', line 57 def clear_lock(name, id) verify_lock_defined!(name) redis.del(redis_field_key("#{name}_lock", id)) end |
#lock(name, options = {}) ⇒ Object
Define a new lock. It will function like a model attribute, so it can be used alongside ActiveRecord/DataMapper, etc.
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# File 'lib/redis/objects/locks.rb', line 17 def lock(name, ={}) [:timeout] ||= 5 # seconds lock_name = "#{name}_lock" redis_objects[lock_name.to_sym] = .merge(:type => :lock) mod = Module.new do define_method(lock_name) do |&block| instance_variable_get("@#{lock_name}") or instance_variable_set("@#{lock_name}", Redis::Lock.new( redis_field_key(lock_name), redis_field_redis(lock_name), redis_objects[lock_name.to_sym] ) ) end end if [:global] extend mod # dispatch to class methods define_method(lock_name) do |&block| self.class.public_send(lock_name, &block) end else include mod end end |
#obtain_lock(name, id, &block) ⇒ Object
Obtain a lock, and execute the block synchronously. Any other code (on any server) will spin waiting for the lock up to the :timeout that was specified when the lock was defined.
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# File 'lib/redis/objects/locks.rb', line 48 def obtain_lock(name, id, &block) verify_lock_defined!(name) raise ArgumentError, "Missing block to #{self.name}.obtain_lock" unless block_given? lock_name = "#{name}_lock" Redis::Lock.new(redis_field_key(lock_name, id), redis_field_redis(lock_name), redis_objects[lock_name.to_sym]).lock(&block) end |