It has been awhile, but I finally made the patch.
Advice and feedback is welcome.
What it does:
- Simplifies the creation of StringField objects. This was already
marked as a TODO in the 3.2.5b code.
- Does not create a file object (cStringIO) for each and every field.
- FieldStorage.get() will always return the same instance(s) for any
given name.
- FieldStorage.get() is very cheap now (does not create new objects,
which is expensive in Python)
It may break:
- Code that creates an instance of Field or StringField directly. This
can be fixed by extending the __init__() routine, but I don't think it's
needed.
It works:
- Perfect on all of my projects.
Attached:
- Patch created by SVN
--
Mike Looijmans
Philips Natlab / Topic Automation
Index: util.py
===================================================================
--- util.py (revision 348746)
+++ util.py (working copy)
@@ -48,19 +48,8 @@
"""
class Field:
- def __init__(self, name, file, ctype, type_options,
- disp, disp_options, headers = {}):
+ def __init__(self, name):
self.name = name
- self.file = file
- self.type = ctype
- self.type_options = type_options
- self.disposition = disp
- self.disposition_options = disp_options
- if disp_options.has_key("filename"):
- self.filename = disp_options["filename"]
- else:
- self.filename = None
- self.headers = headers
def __repr__(self):
"""Return printable representation."""
@@ -81,13 +70,30 @@
self.file.close()
class StringField(str):
- """ This class is basically a string with
- a value attribute for compatibility with std lib cgi.py
- """
+ """ This class is basically a string with
+ added attributes for compatibility with std lib cgi.py. Basically, this
+ works the opposite of Field, as it stores its data in a string, but creates
+ a file on demand. Field creates a value on demand and stores data in a
file.
+ """
+ filename = None
+ headers = {}
+ ctype = "text/plain"
+ type_options = {}
+ disposition = None
+ disp_options = None
+
+ # I wanted __init__(name, value) but that does not work (apparently, you
+ # cannot subclass str with a constructor that takes >1 argument)
+ def __init__(self, value):
+ '''Create StringField instance. You'll have to set name yourself.'''
+ str.__init__(self, value)
+ self.value = value
- def __init__(self, str=""):
- str.__init__(self, str)
- self.value = self.__str__()
+ def __getattr__(self, name):
+ if name != 'file':
+ raise AttributeError, name
+ self.file = cStringIO.StringIO(self.value)
+ return self.file
class FieldStorage:
@@ -103,8 +109,7 @@
if req.args:
pairs = parse_qsl(req.args, keep_blank_values)
for pair in pairs:
- file = cStringIO.StringIO(pair[1])
- self.list.append(Field(pair[0], file, "text/plain", {}, None,
{}))
+ self.add_field(pair[0], pair[1])
if req.method != "POST":
return
@@ -123,9 +128,7 @@
if ctype.startswith("application/x-www-form-urlencoded"):
pairs = parse_qsl(req.read(clen), keep_blank_values)
for pair in pairs:
- # TODO : isn't this a bit heavyweight just for form fields ?
- file = cStringIO.StringIO(pair[1])
- self.list.append(Field(pair[0], file, "text/plain", {}, None,
{}))
+ self.add_field(pair[0], pair[1])
return
if not ctype.startswith("multipart/"):
@@ -205,33 +208,44 @@
else:
name = None
+ # create a file object
# is this a file?
if disp_options.has_key("filename"):
if file_callback and callable(file_callback):
file = file_callback(disp_options["filename"])
else:
- file = self.make_file()
+ file = tempfile.TemporaryFile("w+b")
else:
if field_callback and callable(field_callback):
file = field_callback()
else:
- file = self.make_field()
+ file = cStringIO.StringIO()
# read it in
- end_of_stream = self.read_to_boundary(req, boundary, file)
+ self.read_to_boundary(req, boundary, file)
file.seek(0)
-
+
# make a Field
- field = Field(name, file, ctype, type_options, disp, disp_options,
headers)
-
+ if disp_options.has_key("filename"):
+ field = Field(name)
+ field.filename = disp_options["filename"]
+ else:
+ field = StringField(file.read())
+ field.name = name
+ field.file = file
+ field.type = ctype
+ field.type_options = type_options
+ field.disposition = disp
+ field.disposition_options = disp_options
+ field.headers = headers
self.list.append(field)
- def make_file(self):
- return tempfile.TemporaryFile("w+b")
+ def add_field(self, key, value):
+ """Insert a field as key/value pair"""
+ item = StringField(value)
+ item.name = key
+ self.list.append(item)
- def make_field(self):
- return cStringIO.StringIO()
-
def read_to_boundary(self, req, boundary, file):
previous_delimiter = None
while True:
@@ -288,11 +302,7 @@
found = []
for item in self.list:
if item.name == key:
- if isinstance(item.file, FileType) or \
- isinstance(getattr(item.file, 'file', None), FileType):
- found.append(item)
- else:
- found.append(StringField(item.value))
+ found.append(item)
if not found:
raise KeyError, key
if len(found) == 1:
@@ -333,11 +343,7 @@
""" return the first value received """
for item in self.list:
if item.name == key:
- if isinstance(item.file, FileType) or \
- isinstance(getattr(item.file, 'file', None), FileType):
- return item
- else:
- return StringField(item.value)
+ return item
return default
def getlist(self, key):
@@ -347,11 +353,7 @@
found = []
for item in self.list:
if item.name == key:
- if isinstance(item.file, FileType) or \
- isinstance(getattr(item.file, 'file', None), FileType):
- found.append(item)
- else:
- found.append(StringField(item.value))
+ found.append(item)
return found
def parse_header(line):
