[issue23539] Content-length not set for HTTP methods expecting body when body is None

[James Rutherford]

James Rutherford added the comment:

Updated docs look good to me, thanks!

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[R. David Murray]

R. David Murray added the comment:

Thanks James and Demien.  I decided to rewrite the 'request' docs for Python3 
to make them easier to follow (and more accurate).  Hopefully I didn't make any 
mistakes, but you might want to review it just in case.

--
resolution:  -> fixed
stage: commit review -> resolved
status: open -> closed

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[Roundup Robot]

Roundup Robot added the comment:

New changeset 5c3dc817ffd7 by R David Murray in branch '2.7':
#23539: Set Content-Length to 0 for PUT, POST, and PATCH if body is None.
https://hg.python.org/cpython/rev/5c3dc817ffd7

New changeset f6f72422df96 by R David Murray in branch '3.4':
#23539: Set Content-Length to 0 for PUT, POST, and PATCH if body is None.
https://hg.python.org/cpython/rev/f6f72422df96

New changeset 643471ed8415 by R David Murray in branch 'default':
Merge: #23539: Set Content-Length to 0 for PUT, POST, and PATCH if body is None.
https://hg.python.org/cpython/rev/643471ed8415

--
nosy: +python-dev

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[Demian Brecht]

Demian Brecht added the comment:

One super minor comment left in Rietveld (py3 patch). Otherwise LGTM.

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[Berker Peksag]

Changes by Berker Peksag :


--
nosy: +berker.peksag

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[James Rutherford]

James Rutherford added the comment:

Updated 2.7 patch attached.

--
Added file: http://bugs.python.org/file38570/issue23539-py27.patch

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[James Rutherford]

James Rutherford added the comment:

Python 3 patch attached. The documentation has changed structure a little so 
I've adapted (simplified) this from the original. Otherwise, it's pretty much 
the same, except with python3 fixes, and incorporated feedback. I'll upload an 
updated 2.7 patch as well in a few minutes.

--
Added file: http://bugs.python.org/file38569/issue23539-py3.patch

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[James Rutherford]

James Rutherford added the comment:

Ok I'll have a go at a consolidated python3 patch tomorrow.

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[R. David Murray]

R. David Murray added the comment:

It would...I've started twice to do the commit and gotten interrupted both 
times.  Having a patch I can just apply would help.  If you would be willing to 
also generate a patch for python3, that would be a help as well.

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[James Rutherford]

James Rutherford added the comment:

Hi all, apologies for the spam, but I just wanted to confirm that no-one is 
waiting on anything from me... I'm happy to consolidate the final minor points 
& make the patch against python3 if that would simplify things.

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[James Rutherford]

James Rutherford added the comment:

Single patch against default makes sense and I'll do that in future.

As for the review comments, I'm happy to go with all of your suggestions but 
have offered a tweak to the docstring that you can take or leave at your 
discretion :)

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[R. David Murray]

R. David Murray added the comment:

Single patch, yes, but FYI we actually prefer a python3 patch against default 
as the single patch.  (Unless there are major differences, which there aren't 
in this case.)

I've made some minor review comments.  You can either ack my changes (or 
disagree :) and I'll make them when I commit, or update the patch yourself if 
you are so moved.

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[Demian Brecht]

Changes by Demian Brecht :


--
stage: patch review -> commit review

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[Demian Brecht]

Demian Brecht added the comment:

> OK, sounds like we're approaching consensus? And I believe that the patch 
> as-is captures that consensus

Yes, I believe that we’ve reached a consensus and that your patch captures it. 
Thanks for the work!

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[Senthil Kumaran]

Senthil Kumaran added the comment:

One patch should be enough, @James. The committer will take care of
porting. Thanks!  ( I am yet to completely read the discussion/ review the
patch and I will do that shortly.)

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[James Rutherford]

James Rutherford added the comment:

OK, sounds like we're approaching consensus? And I believe that the patch as-is 
captures that consensus, so should I proceed and make another for 3.X for 
review?

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[R. David Murray]

R. David Murray added the comment:

Not to get into an API argument, but rather to convey some Python philosophy as 
I understand it: there *is* often a distinction in Python between the value 
'None' and a boolean-False-value like ''.  It is often the case in Python APIs 
that None means something different from other arguably-semantically-equivalent 
values.  In this case I believe it is entirely logical that 'None' (the default 
value) for a method that does not normally take a body and makes a distinction 
based on Content-Length (or some other header) makes sense, and that explicitly 
saying "I want an empty body, including the standard headers" is actually a 
sensible Python API.  If we were designing it from scratch with these issues in 
mind, we might well come up with exactly what we've got...or we might not, 
because wanting to specify an empty body on such a command is a really low 
probability event :)

Regardless, we're constrained by backward compatibility here, so the question 
is moot.

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[Demian Brecht]

Demian Brecht added the comment:

> Aside from that, however, I see request.('GET', '/') and request.('GET', '/', 
> '') as clearly *different* from an API call standpoint, so I would in any 
> case preserve the existing behavior.

I do understand the case that the the two examples look different from a 
caller’s standpoint. However as a user, I’d expect the library to do the Right 
Thing due to a deeper understanding of the theory behind the API that I’m 
using. Perhaps it would have made more sense to default body to empty string 
rather than None in which case there wouldn’t be a need for this distinction.

That said, I do understand the reasoning behind not breaking backwards 
compatibility and it’s not a problem until reported and am not looking to get 
into an API design argument (especially for something as low impact as what I 
was proposing). So @James, I stand corrected :)

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[R. David Murray]

R. David Murray added the comment:

Don't break backward compatibility.  It's not like this was reported as a bug 
that caused a problem for real world code, it is about theoretical consistency. 
 The risk of breaking someone code is much higher than the benefit of any such 
consistency, when talking about a bug fix.

Aside from that, however, I see request.('GET', '/') and request.('GET', '/', 
'') as clearly *different* from an API call standpoint, so I would in any case 
preserve the existing behavior.

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[Demian Brecht]

Demian Brecht added the comment:

+David, Senthil: Thoughts on this?

--
nosy: +orsenthil, r.david.murray

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[Demian Brecht]

Demian Brecht added the comment:

> but I wonder if that goes beyond the scope of this issue?

I think it’s worthwhile to fix it while you’re already working on the logic 
there. I’d consider Content-Type being set for methods not expecting it as a 
(very) minor bug and it’s better to clear up the inconsistent behaviour. That 
said, it /is/ breaking backwards compatibility (however slightly) and would 
likely need to get sign-off from a couple core devs.

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[James Rutherford]

James Rutherford added the comment:

>> My feeling is that '' implies "present but empty" (so should have a 
>> content-length set to zero), whereas None implies "missing" (so should only 
>> have a content-length header set to zero if the method is expecting a body.
> ...
> In light of that, I think that HTTPConnection(‘example.com’).request(‘GET’, 
> ‘/‘, ‘’) and HTTPConnection(‘example.com’).request(‘GET’, ‘/‘) should result 
> in identical headers with no Content-Length set.

I get your reasoning here, but I wonder if that goes beyond the scope of this 
issue? My initial thinking was the same, but then realised that was 
inconsistent with the current behaviour. For example, a GET with '' in the body 
already sets content-length: 0, but a GET with None for the body doesn't set a 
content length at all. I haven't changed this behaviour in my patch, except for 
PUT, POST, and PATCH where None and '' are now equivalent for those methods.

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[Demian Brecht]

Demian Brecht added the comment:

> I actually consider this a fix for the fix in 14721, rather than a new 
> feature.

+1

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[Demian Brecht]

Demian Brecht added the comment:

> My feeling is that '' implies "present but empty" (so should have a 
> content-length set to zero), whereas None implies "missing" (so should only 
> have a content-length header set to zero if the method is expecting a body.

Although I understand your thinking here, I think that bodies that are either 
None or empty string should be treated identically. Whether or not the 
Content-Length header is set should be dependent on the method used.

>From a client standpoint, there’s no difference between sending a body with a 
>value of None and an empty string (the latter will get further down the call 
>stack, but no data is actually sent over the wire).

Likewise from the server standpoint, there is no functional difference between 
a missing or empty body. However, there’s still the possibility of unexpected 
behaviour due to the inclusion of a Content-Length header for a method not 
expecting it.

In light of that, I think that HTTPConnection(‘example.com’).request(‘GET’, 
‘/‘, ‘’) and HTTPConnection(‘example.com’).request(‘GET’, ‘/‘) should result in 
identical headers with no Content-Length set.

If someone /really/ wants to set the Content-Length header for a method that 
doesn’t expect it, they still have the ability to do so: 
HTTPConnection(‘example.com’).request(‘GET’, ‘/‘, ‘’, {‘Content-Length’: 0}). 
However, if the default behaviour is to include the Content-Length header for 
an empty string, the user then has to change what they’re sending to be None 
instead of empty string even though they should be functionally equivalent.

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[James Rutherford]

James Rutherford added the comment:

I actually consider this a fix for the fix in 14721, rather than a new feature. 
The only new behaviour here is setting content length to be zero if body is 
None on PATCH, POST, or PUT. Happy to change the labeling if that's the 
consensus but IMO it's a bugfix.

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[Martin Panter]

Martin Panter added the comment:

Yes I agree with the behaviour that None means no body (for requests such as 
GET), and an empty string means an empty but present body. Correct me if I’m 
wrong, but I think the fix for Issue 14721 already does that.

Perhaps the new behaviour needs a “Changed in version X” tag? I’m not sure, but 
I tend to think of this as a new feature, rather than a bug fix.

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[James Rutherford]

James Rutherford added the comment:

Happy to remove OPTIONS from the list of methods that gets a content-length 
where body is None, but do we also want to consider behaviour if it's the empty 
string? My feeling is that '' implies "present but empty" (so should have a 
content-length set to zero), whereas None implies "missing" (so should only 
have a content-length header set to zero if the method is expecting a body.

I've updated the patch with this logic, including ensuring proper explicit test 
coverage for the cases described. Docs updated too.

--
Added file: http://bugs.python.org/file38276/issue23539-py27.patch

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[Demian Brecht]

Demian Brecht added the comment:

> Also, I think OPTIONS should be removed from the list of methods that enforce 
> a Content-Length. I wouldn’t normally expect any payload for OPTIONS, since 
> RFC 7231 explicitly says it does not define a use for a payload, but requires 
> a Content-Type if a payload is sent.

I think Martin's right about this and it's consistent with my concern about 
servers treating the existence of a Content-Length header as an indicator of a 
request body.

In any event, with the new logic, a Content-Length header will be added if the 
body is not None.

> I've just put the logic inside _set_content_length

Fair enough. It /does/ encapsulate all logic around setting the content length 
within the method.


I've left a couple minor comments in Rietveld. In addition to what's there, 
docs should also be updated to reflect the new behaviour.

Thanks for the work on this!

--
stage: needs patch -> patch review

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[James Rutherford]

James Rutherford added the comment:

The first patch should actually be modified so the condition reads (update 
attached):

if body is None and method_expects_body:
thelen = 0
elif body is not None:
...

Demian, I believe this is equivalent to your 'expecting_len' proposal, I've 
just put the logic inside _set_content_length. My approach was to leave as much 
existing logic as possible in place to avoid the introduction of new bugs 
(first patch wasn't entirely successful in this!).

As for OPTION, 

   If the OPTIONS request includes a message-body (as indicated by the
   presence of Content-Length or Transfer-Encoding), then the media type
   MUST be indicated by a Content-Type field.  Although this
   specification does not define any use for such a body, future
   extensions to HTTP might use the OPTIONS body to make more detailed
   queries on the server.

>From http://tools.ietf.org/html/draft-ietf-httpbis-p2-semantics-14#section-7.2

--
Added file: http://bugs.python.org/file38270/issue23539-py27.patch

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[Martin Panter]

Martin Panter added the comment:

I like Demian’s “expecting_len” technique slightly better because it would 
avoid calling None.fileno() and len(None), as Demian just said.

Also, I think OPTIONS should be removed from the list of methods that enforce a 
Content-Length. I wouldn’t normally expect any payload for OPTIONS, since RFC 
7231 explicitly says it does not define a use for a payload, but requires a 
Content-Type if a payload is sent.

--
nosy: +vadmium

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[Demian Brecht]

Demian Brecht added the comment:

> The logic now is as it was before, except that we set a content length of 
> zero if the body is None and the method is one of OPTIONS, PATCH, PUT, or 
> POST.

I see we definitely have similar thinking on the modifications required for 
this, but I don’t think I’m in favour of the approach in the patch. Consider 
the case where you have a GET request without a body. Now, instead of simply 
circumventing the _set_content_length method altogether as would have been done 
previously, the code path will now go into _set_content_length, have a 
TypeError exception raised on (str(len([None])) and then an AttributeError 
exception raised on os.fstat([None].fileno()). That seems to be quite a bit of 
additional overhead when it could be avoided altogether by an earlier check as 
I have in my example.

What do you think?

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[Demian Brecht]

Demian Brecht added the comment:

My concern about this is around the combination of the following two passages:

draft-ietf-httpbis-p2-semantics-14, Section 7.3:

>   Bodies on GET requests have no defined semantics.  Note that sending
>   a body on a GET request might cause some existing implementations to
>   reject the request.

RFC 7230, Section 3.3.2:

> The presence of a message body in a request is signaled by a Content-Length 
> or Transfer-Encoding header field.

My concern around the above is the possibility that servers may have 
implementations that reject requests with methods that are not expecting bodies 
solely on the existence of the Content-Length header rather than the value 
(which may be 0). Without a good amount of research around whether or not this 
would be an actual problem in practice, I wouldn’t be comfortable adding 
Content-Length header to every request.

> My feeling is that stripping out Content-Length for GET requests could cause 
> problems for some code that for whatever reason uses this

That’s definitely a valid concern. What if the logic was tweaked a little:

expecting_len = method.upper() in _METHODS_EXPECTING_BODIES or \
body is not None

if expecting_len and 'content-length' not in header_names:
self._set_content_length(body)

That way, if someone is intentionally sending a body in a GET request, the 
value of Content-Length would still be automatically added, but would still be 
set to 0 for all other cases where bodies are expected.

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[James Rutherford]

James Rutherford added the comment:

Patch attached for the 2.7 branch, including updated tests. All tests pass. Let 
me know if this looks like a sensible approach and I'll produce something 
comparable for 3.X. 

The logic now is as it was before, except that we set a content length of zero 
if the body is None and the method is one of OPTIONS, PATCH, PUT, or POST.

--
keywords: +patch
Added file: http://bugs.python.org/file38267/issue23539-py27.patch

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[James Rutherford]

James Rutherford added the comment:

OK, I've got a patch but it's failing on 'test_send_file'[1], which is sending 
a body on a GET request. According to the IETF memo[2]:

   Bodies on GET requests have no defined semantics.  Note that sending
   a body on a GET request might cause some existing implementations to
   reject the request.

So I don't know whether to remove the method constraint so this test passes, or 
to "fix" this test to use a different method. My feeling is that stripping out 
Content-Length for GET requests could cause problems for some code that for 
whatever reason uses this, so we should remove that constraint (it was only 
"SHOULD NOT" after all) and go back to the original proposal of just setting 
the content length for bodies that are None as well as empty strings.

[1] 
https://hg.python.org/cpython/file/325aec842e3e/Lib/test/test_httplib.py#l297
[2] http://tools.ietf.org/html/draft-ietf-httpbis-p2-semantics-14#section-7.3

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[James Rutherford]

James Rutherford added the comment:

OK, thanks.

--
versions:  -Python 3.2, Python 3.3

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[Demian Brecht]

Demian Brecht added the comment:

> I'm assuming this affects all Python 3.X versions but I've specifically 
> encountered it on Python 2.7.

Unless there are any core dev objections, I think it's applicable to 2.7, 3.4 
and 3.5 as other minor 3.x versions are in security mode 
(https://docs.python.org/devguide/devcycle.html#security-branches).

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[James Rutherford]

James Rutherford added the comment:

Thanks for setting up the new issue, I'll cook up a patch. I'm assuming this 
affects all Python 3.X versions but I've specifically encountered it on Python 
2.7.

--
nosy: +jimr
versions: +Python 2.7, Python 3.2, Python 3.3, Python 3.4

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue23539] Content-length not set for HTTP methods expecting body when body is None

[Demian Brecht]

New submission from Demian Brecht:

#14721 solved setting the Content-Length header for 0-length bodies. However, 
it doesn't account for cases where body is None (reported by James Rutherford 
here: http://bugs.python.org/issue14721#msg236600).

One method of solving this might be something like this:

_METHODS_EXPECTING_BODIES = {'OPTIONS', 'POST', 'PUT', 'PATCH'}
if method.upper() in _METHODS_EXPECTING_BODIES and \
'content-length' not in header_names:
self._set_content_length(body)

(_set_content_length would have to be updated in order to allow for None)

This ensures that Content-Length will not be set for methods not expecting a 
body.

RFC 7230, Section 3.3.2:

   A user agent SHOULD NOT send a Content-Length header field when the
   request message does not contain a payload body and the method 
   semantics do not anticipate such a body.

--
components: Library (Lib)
messages: 236803
nosy: demian.brecht
priority: normal
severity: normal
stage: needs patch
status: open
title: Content-length not set for HTTP methods expecting body when body is None
type: behavior
versions: Python 3.5

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com