Anders Blomdell wrote:
> Hi,
>
> When a FieldStorage has two (or more) Filed instances with the same value but
> different names, the behaviour of programs like this is (more or less)
> undefined:
>
> fs = util.FieldStorage(req)
> fs['id1'] = 'New value'
> del fs['id2']
>
> The reason for the undefinedness, is this code in __delitem__ (and the similar
> in __setitem__):
>
> table = self.list.table()
> values = table[key]
> for value in values:
> self.list.remove(value)
>
> What happens is that the self.list.remove(value) will remove the first field
> with a matching value, regardless of that fields name. Here is an example from
> real life:
>
> form.clear()
> form['id1'] = 'x'
> form['id2'] = 'x'
> form['id3'] = 'x'
> # Form now contains {'id2': [Field('id2', 'x')],
> # 'id3': [Field('id3', 'x')],
> # 'id1': [Field('id1', 'x')]}
> form['id2'] = 'y'
> # Form now contains {'id2': [Field('id2', 'x'), Field('id2', 'y')],
> # 'id3': [Field('id3', 'x')]}
> # which is not what I would have expected
>
>
> In my simple example, one solution, is to add the following method to
> StringField:
>
> def __eq__(self, other):
> return self.value == other.value and self.name == other.name
>
> but this does not properly handle mixing Field and StringField. Anybody has a
> better solution?
Some more thinking made me come up with the patch below.
Regards
Anders
--- /usr/lib/python2.6/site-packages/mod_python/util.py.orig 2006-11-22
12:15:54.000000000 +0100
+++ /usr/lib/python2.6/site-packages/mod_python/util.py 2010-03-01
16:00:30.000000000 +0100
@@ -145,6 +145,12 @@
self.__table[item.name] = [item]
return self.__table
+ def delete_name(self, name):
+ self.__table = None
+ for i in range(len(self) - 1, -1, -1):
+ if self[i].name == name:
+ self.pop(i)
+
def __delitem__(self, *args):
self.__table = None
return list.__delitem__(self, *args)
@@ -348,11 +354,8 @@
self.list.append(item)
def __setitem__(self, key, value):
- table = self.list.table()
- if table.has_key(key):
- items = table[key]
- for item in items:
- self.list.remove(item)
+ if self.list.table().has_key(key):
+ self.list.delete_name(key)
item = StringField(value)
item.name = key
self.list.append(item)
@@ -460,10 +463,8 @@
return [(item.name, item) for item in self.list]
def __delitem__(self, key):
- table = self.list.table()
- values = table[key]
- for value in values:
- self.list.remove(value)
+ if self.list.table().has_key(key):
+ self.list.delete_name(key)
def clear(self):
self.list = FieldList()
--
Anders Blomdell Email: [email protected]
Department of Automatic Control
Lund University Phone: +46 46 222 4625
P.O. Box 118 Fax: +46 46 138118
SE-221 00 Lund, Sweden
