ok, I guess that the answer is no... (or I didn't formulate the question correctly....)
On Thu, Jan 19, 2012 at 11:51 PM, sebastian <[email protected]>wrote: > Hi All, > > just thinking on how to implement a distributed locking system in web2py > using a DB: one row per each lock, lock_name is unique, if the row doesn't > exist, then it is locked, if the row exist already, then it cannot be lock > as it is already locked ! > > I'd like to create a module like this (that can be called from anywhere in > web2py) > > def lock(lock name): > begin transaction > does the row exist ? > no => insert new row > commit transaction > return result > > def unlock(lock_name): > begin transaction > delete row where name = lock_name > commit transaction > > > BUT.... not sure if this is possible (of course it is !) in web2py... > > consider this controller > > def hello1(): > do a lot of things > db.commit() > do more things in the DB > > ### here is my doubt: ####################### > if lock("some resource"): ### I'm calling a method that opens and > close a transaction inside a transaction !!! > do something > unlock("some resource") > else > do something else > > #### another example ####################3 > if lock("resource A"): > if lock("resource B"): > do a lot of things woth both resources > unlock("resource B") > unlock("resource A") > else > so other things > unlock("resource A") > > do more things > > db.commit() > do more staff > > > any better idea ? > > thansk > -- Sebastian E. Ovide
