Python 2.5 nested auth functions in publisher.

• Key: MODPYTHON-198
• Type: Bug
• Status: Closed
• Resolution: Fixed
• Priority: Major
• Assignee: Graham Dumpleton
• Reporter: Graham Dumpleton
• Component/s: publisher
• Affects Version/s: 3.2.10
• Fix Version/s: 3.3.1

Description

Jim Gallacher wrote:

With python 2.5 I get 2 failures:

    test_publisher_auth_nested
    test_publisher_auth_method_nested

It looks like something has changed in python 2.5 introspection that is
messing up publisher.

Test script testme.py
---------------------

def testfunc():
     print 'stuff'
     def __auth__():
         print '__auth__ called'
     def __access__():
         print '__access__ called'

def main():
     func_obj = testfunc

     func_code = func_obj.func_code
     print func_code.co_names

if __name__ == '__main__':
     main()

Results
-------

$ python2.3 testme.py
('__auth__', '__access__')
$ python2.4 testme.py
('__auth__', '__access__')
$ python2.5 testme.py
()


Dan Eloff points out that information is now in co_varnames.

>>> fc.co_names
()
>>> fc.co_varnames
('__auth__', '__access__')

>>> def foo(a,b):
d = 5
def bar(c):
return c

>>> fc.co_names
()
>>> fc.co_varnames
('a', 'b', 'd', 'bar')

To get just args, try:

>>> fc.co_varnames[:fc.co_argcount]
('a', 'b')

And for just local vars:

>>> fc.co_varnames[fc.co_argcount:]
('d', 'bar')


Still need to work out if actual code objects for the functions are available in co_consts or not. Ie., need to replace:

        if "__auth__" in func_code.co_names:
            i = list(func_code.co_names).index("__auth__")
            __auth__ = func_code.co_consts[i+1]
            if hasattr(__auth__, "co_name"):
                __auth__ = new.function(__auth__, func_globals)
            found_auth = 1

Comments

Dan provides confirmation that something like:

>>> def foo(a,b):
d = 5
def __auth__(req):
return True
e = d + 5

>>> fc = foo.func_code
>>> import new
>>> func_globals = globals()
>>> for i, var_name in enumerate(fc.co_varnames):
if var_name == '__auth__':
__auth__ = fc.co_consts[i-fc.co_argcount+1]
if hasattr(__auth__, 'co_name'):
__auth__ = new.function(__auth__, func_globals)
found_auth = 1
break

>>> __auth__
<function __auth__ at 0x01159830>

would appear to work.

In practice need to support old and new versions of Python, so will need to check both co_names and co_varnames.

[Graham Dumpleton]

Looks like JIRA is not showing subversion commits or has not recorded some from when they were doing their infrastructure update. Is fixed though. Ended up using:

        func_code = func_object.func_code
        func_globals = func_object.func_globals

        def lookup(name):
            i = None
            if name in func_code.co_names:
                i = list(func_code.co_names).index(name)
            elif func_code.co_argcount < len(func_code.co_varnames):
                names = func_code.co_varnames[func_code.co_argcount:]
                if name in names:
                    i = list(names).index(name)
            if i is not None:
                return (1, func_code.co_consts[i+1])
            return (0, None)

        (found_auth, __auth__) = lookup('__auth__')
        if found_auth and type(__auth__) == types.CodeType:
            __auth__ = new.function(__auth__, func_globals)

        (found_access, __access__) = lookup('__access__')
        if found_access and type(__access__) == types.CodeType:
            __access__ = new.function(__access__, func_globals)

        (found_realm, __auth_realm__) = lookup('__auth_realm__')
        if found_realm:
            realm = __auth_realm__

Ie., look in co_names first as co_varnames wasn't ordered correctly for older versions of Python.