[Patches] [ python-Patches-1159139 ] cgi.py invalid REQUEST_METHOD set

[SourceForge.net]

Patches item #1159139, was opened at 2005-03-08 11:04
Message generated for change (Comment added) made by joesalmeri
You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=305470&aid=1159139&group_id=5470

Please note that this message will contain a full copy of the comment thread,
including the initial issue submission, for this request,
not just the latest update.
Category: Library (Lib)
Group: Python 2.4
Status: Closed
Resolution: Rejected
Priority: 5
Private: No
Submitted By: Joe (joesalmeri)
>Assigned to: Martin v. Löwis (loewis)
Summary: cgi.py invalid REQUEST_METHOD set

Initial Comment:
Python Version 2.4
OS Windows XP SP 2 + WindowsUpdates
Patch for lastest CVS Tree

When the environment does not have a correctly set 
REQUEST_METHOD cgi.py prompts
for key=value pairs by reading from sys.stdin.  After the 
values are read from sys.stdin they are never stored in 
the FieldStorage.list attribute like they are
when the FieldStorage.read_urlencoded or 
FieldStorage.read_multi methods are called.

This causes a problem when FieldStorage.keys() is 
called because although the values were read from 
sys.stdin they were never stored in FieldStorage.list.

Although you could argue that REQUEST_METHOD 
should have been set correctly in the first place, it still 
seems like if cgi.py is going to handle that situation by
actually reading the values from sys.stdin it should 
store them too.

This fix stores the values read.


----------------------------------------------------------------------

>Comment By: Joe (joesalmeri)
Date: 2007-04-02 09:54

Message:
Logged In: YES 
user_id=1235002
Originator: YES

It been a long time since I submitted this patch but I meant that
REQUEST_METHOD is not set although I believe it also happens when it is set
incorrectly.

Regarding your question with the prompting I thought I explained that in
the original post but here are more details:

When the REQUEST_METHOD is not set the __init__ method for the
FieldStorage class ends up setting the self.fp to sys.stdin.

When the read_single method is called it calls self.read_lines().  Since
self.fp is equal to sys.stdin at that point and since there is not input
pending on stdin it ends up prompting for input until it reaches EOF.

The bug was that although it prompted for input by reading from sys.stdin,
the values that it read were never stored in FieldStorage like they are
when the values are read from the normal sources.  

Since someone went to the trouble of coding cgi.py to read the values from
stdin when the REQUEST_METHOD was invalid it seems to make sense to store
them.

As jimjjewett point out this addresses the issue of allowing a cgi script
to be called from the command line which is useful for debugging of if no
web server is running.

Since it is counter-intuitive to read the values or not store them the
other option would be not to set self.fp = sys.stdin and instead through an
error that REQUEST_METHOD was not set properly however, it seems more
benefitial to read from sys.stdin and then store the values read in
FieldStorage.

Does that make more sense now?

Thanks.












----------------------------------------------------------------------

Comment By: SourceForge Robot (sf-robot)
Date: 2007-03-20 22:20

Message:
Logged In: YES 
user_id=1312539
Originator: NO

This Tracker item was closed automatically by the system. It was
previously set to a Pending status, and the original submitter
did not respond within 14 days (the time period specified by
the administrator of this Tracker).

----------------------------------------------------------------------

Comment By: Martin v. Löwis (loewis)
Date: 2007-03-06 08:23

Message:
Logged In: YES 
user_id=21627
Originator: NO

I must be completely missing the point of this patch. 

Where in the code does it currently prompt for key=value pairs if
REQUEST_METHOD is not correctly set?

By "not correctly set", do you mean "not set" or "set incorrectly"? If the
latter, to what value?

You seem to be modifying the read_single function. This is meant to read a
single body of the CGI request (as sent by the HTTP client), not the
key-value-pairs.

I've tried to come up with a demo application of this new functionality,
but failed: I couldn't make this new code do anything useful. What Python
script should I use, how should I invoke it, what environment variables
should I give, and what standard input?

Tentatively rejecting the patch.

----------------------------------------------------------------------

Comment By: Jim Jewett (jimjjewett)
Date: 2005-03-14 17:54

Message:
Logged In: YES 
user_id=764593

+1 on supporting use without a REQUEST_METHOD, if only 
to match Perl on "what happens if my .cgi was called straight 
from the command line"?
 

----------------------------------------------------------------------

You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=305470&aid=1159139&group_id=5470