Re: [web2py] cluster: distributed locks
yes... very similar... I guess that just deleting the JS part and creating
a new DB object within the plugin (so that it has it own ttransaction)
will make the work...
thanks
On Thu, Jan 26, 2012 at 9:20 AM, Bruno Rocha wrote:
> I dont know if it is related, but there is a Locking plugin
>
> http://web2py.com/plugins/default/locking
>
>
> On Thu, Jan 26, 2012 at 7:05 AM, Sebastian E. Ovide <
> sebastianov...@gmail.com> wrote:
>
>> 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 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
>>
>>
>>
>>
>
>
> --
>
> Bruno Rocha
> [http://rochacbruno.com.br]
>
>
--
Sebastian E. Ovide
Re: [web2py] cluster: distributed locks
I dont know if it is related, but there is a Locking plugin
http://web2py.com/plugins/default/locking
On Thu, Jan 26, 2012 at 7:05 AM, Sebastian E. Ovide <
sebastianov...@gmail.com> wrote:
> 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 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
>
>
>
>
--
Bruno Rocha
[http://rochacbruno.com.br]
Re: [web2py] cluster: distributed locks
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 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
[web2py] cluster: distributed locks
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
