Invalid lookup in ormcache()

Hello Thibaut DIRLIK ,

I have checked this issue at my end. in ormcache() in lookup() method , Line 41
r = d[key] if it cause KeyError then it handle by except KeyError:
line 46 " value = d[args] = self.method(self2, cr, *args)".
but I did not face any problem regarding this issue.

So would you please elaborate more regarding this issue.

Thanks and waiting for reply!

In fact, the problem is the following :

1) You check if the data already is in the cache : d[key]
2) If it's the case, you return it.
3) If it's not the case, you get the value, and save it in the dictionnary "d".

The problem is that when you save the value, you set d[args] instead of d[key]. So, imagine :

key = 'a'
args 'b'

d[key] => Not cached
Then
d[args] = Result => THIS IS WRONG ! It should be d[key] = Result !

In our case, args is the same than key if self.skipargs = 2. However, if self.skipargs is defferent than 2, they won't be the same, and the value will never get cached correctly.

Hello Thibaut ,

I have checked this again but as your comment #2 I am not getting any problem
regarding this issue.As per line 46 value = d[args] = self.method(self2, cr, *args).
set result value , d[args] by self.method(self2, cr, *args).
means if a = b = c then it set a =c and b = c , So d[args] does not change return value.
So would you please provide proper test case to reproduce this issue.
Or provide a video related to bug.

Thanks and waiting reply!

I'm sorry, you don't understand what's the problem.

You set a value in the cache using a key (d[key]) and you use an other key (d[args]) to check if it is present in the cache. The "args" variable is based on the "skipargs" arguments, whereas the "key" variable is not.

Pseudo code:

if key not in d:
    d[args] = VALUE

If key != args, the cache won't work.

Hello,

Thibaut is perfectly right, this is apparently a typo that makes the system store cached data with the wrong key whenever skiparg != 2. This basically disables the cache and makes it useless for those cases.
In particular our translation system is affected, because ir.transalation.get_source() uses skiparg=3, so it means the cache does not work for translations at the moment.
This should not cause any bug, but makes the cache system useless in those cases, and might have an impact on performance.

Jignesh, if you want to convince yourself the easiest method is probably to add a print statement after line 46 of tools.cache, and then open any menu in your OpenERP client (e.g Customer list). When you click on the same menu again you should not see any printed lines because all translations should be cached... but in fact you will see them again, and every time you refresh.
Now if you replace d[args] with d[key] on line 46 and try again, you will see that it works as expected.

The fix will be applied soon, however I'd love to have a unit test for this... writing one is quite easy as we have a cache miss counter already.

The fix has landed in 6.1 at revision 4175 rev-id: <email address hidden>.
It will be ported to trunk next time 6.1 is merged.

(It also revealed a cache invalidation bug in the decimal_precision module, fixed in addons at rev.6807 rev-id: <email address hidden>)