Gianugo Rabellino wrote:
On Tue, 27 Jul 2004 14:57:08 +0200, Daniel Fagerstrom
<[EMAIL PROTECTED]> wrote:
I was thinking about using SWT as well, but then I realized that SWT
doesn't offer a way of inserting the resulting XML in the original
stream: all it does is delete the XML inside the <source:write/>
element, providing some status information (see SWT#reportResult()).
Am I missing something?
I have extended SWT so that you can post XML as well: <source:post/>.
Oh, I see. Well, I spent a few brain cycles on it, and I have to admit
that I'm not convinced that the Source/SWT way is the way to go. The
idea of a Source, to me, is that whatever I write to it can be read
back at the same location: this happens with files and with HTTP as
well (if you PUT and GET). POST is a different beast and it belongs to
RPC rather than to streams.
I can agree with that the name Source doesn't describe the a POST very
well, protocol would have been better (at least if you want to post and
put things to it). An HTTP POST require an input and an output stream
and that you have completed your writing to the output stream before you
can read from the input stream, so I don't understand what you mean with
that it doesn't belong to streams.
Same issue goes for SWT. Apart from having quite a few discussions
about it (as it "tees" the pipeline, which - design wise - is not a
good idea for many of us), it wasn't quite conceived to do this job.
As you might remember I spent quite a lot of energy trying to convince
the community about the need for selection based on results earlier in
the pipeline, tee functionality and so on ;) Anyway, my current take is
that transformers with side effects are ok for simple use cases, when I
need more advanced control functionality I use flowscripts instead.
Also, I haven't seen your implementation, but is it compatible with
the "old" SWT output in terms of the resulting XML or will it break
compatibility?
It is backward compatible with SWT as it just extends it functionality.
The source:post tag sets the METOD parameter in the source to POST, and
writes the content of the source:fragment element to the output stream
of the source and report the result from the input stream of the source
to the source:sourceResult/source:content element.
All in all, I'd rather favor the transformer approach ATM: it seems to
me that it fits much better in the overall Cocoon architecture: you
build your request inside the pipeline, pass it through a component
which performs the POST and grab the result (something you can,
besides, do a using a cocoon:// src to the WSProxyGenerator). But I'm
open to change my mind.
I don't see how this differs from my approach.
I have a pipeline e.g. FileGenerator -> SWT -> XMLSerializer
the input to SWT is e.g.:
<page>
<source:post xmlns:source="http://apache.org/cocoon/source/1.0";>
<source:source>http://services.xmethods.net:9090/soap</source:source>
<source:header name="Content-Type">text/xml; charset="utf-8"</source:header>
<source:header name="SOAPAction">""</source:header>
<source:fragment>
<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/";
xmlns:xsi="http://www.w3.org/1999/XMLSchema-instance";
xmlns:xsd="http://www.w3.org/1999/XMLSchema";>
<soap:Body>
<ns1:getRate xmlns:ns1="urn:xmethods-CurrencyExchange"
soap:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/";>
<country1 xsi:type="xsd:string">England</country1>
<country2 xsi:type="xsd:string">Japan</country2>
</ns1:getRate>
</soap:Body>
</soap:Envelope>
</source:fragment>
</source:post>
</page>
and the output from SWT:
<page>
<sourceResult xmlns:source="http://apache.org/cocoon/source/1.0";>
<content>
<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/";
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance";
xmlns:xsd="http://www.w3.org/2001/XMLSchema";
xmlns:soapenc="http://schemas.xmlsoap.org/soap/encoding/";
soap:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/";>
<soap:Body>
<n:getRateResponse xmlns:n="urn:xmethods-CurrencyExchange">
<Result xsi:type="xsd:float">183.9227</Result>
</n:getRateResponse>
</soap:Body>
</soap:Envelope>
</content>
<execution>success</execution>
<message>entire source overwritten</message>
<behaviour>post</behaviour>
<action>posted</action>
<source>http://services.xmethods.net:9090/soap</source>
<serializer>xml</serializer>
</sourceResult>
</page>
How does this differ from what you have in mind?
/Daniel
