Hi Alistair,
Thanks - yes, you are right, neither Apache nor mod_wsgi enable chunked
transfer encoding by default. Eventually I found the answer in a change
log on the mod_wsgi scm, which allows you to turn it on :)
Cheers,
Richard
On 12/05/11 11:28, Alistair Miles wrote:
Hi Richard,
I'm far from an expert in either Apache or Abdera, but I'd be surprised if
Apache (at least in the default configuration) allowed posting of content
without a content-length header - I think this would be a potential denial of
service vulnerability.
Cheers,
Alistair
On Sat, Apr 16, 2011 at 01:40:59PM +0100, Richard Jones wrote:
Hi Folks,
I'm a new user with Abdera, and am having some problems getting an
Abdera client to talk to my AtomPub server running behind Apache,
based around chunked Transfer-Encoding, and wonder if anyone can
help.
Basically, I'm executing:
resp = client.execute(
"POST", url.toString(),
new SWORDMultipartRequestEntity(deposit),
options);
Where SWORDMultipartRequestEntity is home-baked but very similar to
MultipartRelatedRequestEntity (it adds a few extra headers at the
Media Part mime boundary and puts a Content-Disposition on the Entry
Part).
When I run this, I get a 411 Content-Length required response, and
the Apache log says:
chunked Transfer-Encoding forbidden: /sss/col-uri/ca0f
I ran a curl command against my AtomPub server:
curl -i -X POST --data-binary "@multipart.dat"
-H 'Content-Type:
multipart/related;boundary="===============0670350989=="'
-H 'MIME-Version: 1.0'
-H 'Packaging: http://purl.org/net/sword/package/default'
http://localhost/sss/col-uri/ca0f
where @multipart.dat is a mock-up of the kind of multipart/related
request I want to make.
The request was successful, and I chased it with wireshark, which
gave me the following output:
POST /sss/col-uri/ca0f HTTP/1.1
User-Agent: curl/7.19.7 (i486-pc-linux-gnu) libcurl/7.19.7
OpenSSL/0.9.8k zlib/1.2.3.3 libidn/1.15
Host: localhost
Accept: */*
Content-Type: multipart/related; boundary="===============0670350989=="
MIME-Version: 1.0
Packaging: http://purl.org/net/sword/package/default
Content-Length: 49557
Expect: 100-continue
HTTP/1.1 100 Continue
So there was a 100 Continue response and then the content deposit
went as planned. When I chase the relevant equivalent bit of code
coming from Abdera I get:
POST /sss/col-uri/ca0f HTTP/1.1
User-Agent: Abdera/v1.0-SNAPSHOT
Host: localhost
Expect: 100-continue
Transfer-Encoding: chunked
Content-Type: Multipart/Related;
boundary="1302955343423";type="application/atom+xml;type=entry"
HTTP/1.1 411 Length Required
The Main differences I can see are:
1/ The Content-Type header from Abdera is slightly differently
constructed (mime boundary accepted) - can't see that this is the
problem.
2/ There is a Transfer-Encoding: chunked header rather than a
Content-Length header in the Abdera call. This seems to be the
culprit.
Perhaps support for Transfer-Encoding: chunked is an option in
Apache, or perhaps I need to set the Content-Length myself? Any
tips gratefully appreciated.
In the mean time, other than that I have to say that Abdera is a joy
to work with - it's giving me lots of space to do the things that I
want.
All the best,
Richard
