Hi everybody,
first of all thank you all guys for helping and sorry for the
delay. I've
been testing the behavior with asynchronous Web Services and got this
results.
1.) The first solution I tried with copying the endpoint references
to the
partnerlink didn't work (as mentioned in the first email), but
according to
the WS-Addressing recommodation, it's not even supposed to, as
there is no
such element like wsa:ReplyTo in the EPR definition.
2.) Then I tried to somehow implement the solution from Mark
(thanks again
for that idea). However, I haven't found anything about that in
docs. So
this is what I've tried:
- the web service should have two operations: one for invoke and
another one for callback
- However, I haven't managed to implement a service like that for
axis2. According to this
http://www.ibm.com/developerworks/webservices/library/ws-axis2/ you
just
have to change the message receiver in service.xml in order for that
service to act asynchronously (in that article, they say it's
supposed to
be
org.apache.axis2.async.AsyncMessageReceiver, but that cannot be
instantiated, you have to use this one
org.apache.axis2.rpc.receivers.RPCInOutAsyncMessageReceiver).
- so I implemented a service with one operation, with asynchronous
message receiver, tested that web service with soapUI and wsa:ReplyTo
header
set up to some address and the asynchronous call worked
- I set up a new portType 'serviceCallbackPT' with an operation
'processServiceCallback' in my BPEL process
- I changed the partnerLinkType to have two roles
<plnk:partnerLinkType name="MyServicePLT">
<plnk:role name="serviceProvider"
portType="remoteServicePortType"/>
<plnk:role name="serviceConsumer" portType="serviceCallbackPT"/>
</plnk:partnerLinkType>
- I changed the partnerLink to have following roles
<bpel:partnerLink name="RemoteServicePartner"
partnerLinkType="MyServicePLT" partnerRole="serviceProvider"
myRole="serviceConsumer" />
- I changed the invoke operation to invoke the webservice without
specifying output variable
- invoke was then followed by receive from the portType defined
for
myRole 'serviceConsumer' from the partnerLink
I runned the process, but wsa:ReplyTo header was still set to
http://www.w3.org/2005/08/addressing/none. So I looked in the ode
source
code (ode 1.3.2) and found out following. In the class
org.apache.ode.axis2.SoapExternalService in the method****
writeHeader()
the
wsa:ReplyTo header is being set up. The url from the EPR for myRole
is set
to wsa:ReplyTo only when jms.reply.destination property for that
EPR is
user
defined (and in that case it looks like
'jms:/user-defined-destination-address') or the url contains (or
starts
with) 'jms:/'. I have no idea why (and actually I don't know what
jms is
:)). So I've changed the code to set up the url from EPR also in
the other
case and it worked. The service was invoked with the wsa:ReplyTo
header
being set up to the address of the 'serviceCallbackPT' (portType for
myRole).
However, ode wasn't able to process the response message, because he
couldn't find the operation for the response message (that actually
happens
in axis message processing, so ode didn't even get the message),
but I
think
it is ws-addressing issue, as the wsa:Action in the message was
indeed set
to false name.
So my result is, that in ode 1.3.2 (release version) it is not
possible to
invoke an asynchronous service, beacuse the wsa:ReplyTo header is
not set
correctly. If anyone knows something more about this issue, please
let me
know.
Bye and thank you again,
Filip
2009/10/9 Håkon Sagehaug <[email protected]>
Hi Mark,
I wanted to try your approach, but I'm not getting the hole
picture I
think
. My test setup is very easy. I've got a echo service, echos the
users
output back, this is of course not a long running task but I
sleep it
for
lets say 1 minute. Here is my wsdl
<message name="SayHiRequestMsg">
<part name="parameters" element="tns:SayHi">
</part>
</message>
<message name="SayHiResponseMsg">
<part name="parameters" element="tns:SayHiResponse">
</part>
</message>
<portType name="EchoServicePortType">
<operation name="SayHi">
<documentation>Just a simple echo operation that returns
the
same
string that is given to it.</documentation>
<input message="tns:SayHiRequestMsg">
</input>
</operation>
</portType>
<portType name="EchoServiceCallbackPortType">
<operation name="onResult">
<input message="tns:SayHiResponseMsg">
</input>
</operation>
</portType>
<binding name="EchoServiceBinding" type="tns:EchoServicePortType">
<soap:binding style="document"
transport="http://schemas.xmlsoap.org/soap/http"; />
<operation name="SayHi">
<soap:operation
soapAction="http://www.bccs.uib.no/EchoService.wsdl/SayHi
"
/>
<input>
<soap:body use="literal" />
</input>
<output>
<soap:body use="literal" />
</output>
</operation>
</binding>
<binding name="EchoServiceCallBackBinding"
type="tns:EchoServiceCallbackPortType">
<soap:binding style="document"
transport="http://schemas.xmlsoap.org/soap/http"; />
<operation name="onResult">
<soap:operation
soapAction="
http://www.bccs.uib.no/EchoService.wsdl/onResult";
/>
<input>
<soap:body use="literal" />
</input>
</operation>
</binding>
<service name="EchoService">
<documentation>This WSDL file describes a simple Echo
Service that
echoes a string sendt to it. This service is intended
primarily
for
testing purposes.</documentation>
<port name="EchoServiceLocal"
binding="tns:EchoServiceBinding">
<soap:address location="
http://129.177.20.77:8080/axis2/services/EchoService"; />
</port>
</service>
I've got a schema that defines the messages. As you see I've got two
ports,
one starting the ws and the other for the callback. So now I'm not
sure
what
to do now. Should the service only bind to the binding for the sayhi
operation, not the call back? I now want to model this in BPEL I
guess
it
would look something like this
<invoke operation="ech:SayHi" portType="ech:EchoServicePortType"
variable="ech:SayHiRequest" />
and receive like this
<receice operation="ech:onResult"
portType="ech:EchoServiceCallbackPortType"
variable="ech:SayHiResonse" />
My questions is then, does ode send ws-addressing header so that
the ws
knows where to respond(1)? What would the service then respond
with(2)?
Since the sayHi operation does not return the actual result, just
empty
or
a
message id. How should the service be implemented, should it
implement
onResult?
Hope you can help with this? I also wanted to first model this with
"normal"
java client.
cheers, Håkon
Then my question is
2009/10/8 Ford, Mark <[email protected]>
With respect to your comment:
“the invoke will be called and waits and times out”
It sounds like you’re trying to model a long running operation as a
request/response operation within WSDL. If you do this, then you’ll
most
likely experience timeouts at the transport layer. A better
implementation
is to split this long running operation into two port types. One to
make
the
request to start the work for the service and the other to
provide an
operation for the service to call you back with the response. The
start
operation would be a one-way operation or a request-response with a
simple
ACK as the response (perhaps with some values to use for
correlation).
This
would be modeled in BPEL by an invoke followed by a receive
activity.
You can create a partnerLinkType to model this by having a
partner role
for
the service you’re invoking and a myRole for your callback point.
In
this
way, the relationship between the two port types is made explicit.
As for ODE, I have not tested this but I would think that there
might
be
a
facility whereby you could have the endpoint reference for the
partnerlink’s
myRole automatically populate as the reply-to header when
invoking a
service. It seems reasonable that the service invocation layer
would
support
this but you’d have to check the docs or the source code to be
sure.
On 10/8/09 4:18 AM, "Michael Dondrup" <[email protected]>
wrote:
Dear Filip,
we are currently working on exactly the same problem, because it
would
be simple and neat solution.
However we didn't get there so far, so maybe it could be
interesting
to have closer look at what it is exactly that doesn't work.
Do you have a process defined, that fails? Then maybe you could
send
the process files so we could have a look it?
We found that the WS-addressing did not seem to work with axis2
1.4.1
and you should try axis2 1.5 on the service side.
To enable wsa support and asynchronous invocation add the
following to
your services.xml within the service tags:
<module ref="addressing" />
<parameter name="messageReceiver.invokeOnSeparateThread">true</
parameter>
There will be other problems however:
- providing the correct port, role and partnerlink type, in the
bpel
process for the service to reply to
- If I try to use a <invoke> and <receive> secence for invoking
the
service, the invoke waits for the service to reply even though the
wsa:replyto works and the invoke will be called and waits and
times
out.
The documentation on this topic is unfortunately totally
incomplete.
Maybe we can try to resolve this together.
Best
Michael
Am 07.10.2009 um 20:40 schrieb Filip Majernik:
Hi,
I want to invoke an asynchronous Web Service from ode, but I
cannot
figure
out how to change wsa:ReplyTo header. I've read about the EPR
configuration
on the ode website and tried something like this:
<bpel:assign>
<bpel:copy>
<bpel:from>
<bpel:literal>
<wsa:EndpointReference xmlns:wsa="
http://www.w3.org/2005/08/addressing";<
http://www.w3.org/2005/08/addressing%22>
<wsa:Address>
http://localhost:8080/axis2/services/MyService</wsa:Address><
http://localhost:8080/axis2/services/MyService%3C/wsa:Address%3E>
<wsa:ReplyTo><wsa:Address>
http://localhost:8080/axis2/services/ReplyToService
</wsa:Address></wsa:ReplyTo>
</wsa:EndpointReference>
</bpel:literal>
</bpel:from>
<bpel:to partnerLink="testPartnerLink"/>
</bpel:copy>
</bpel:assign>
but it isn't working. Does anyone maybe have a working example of
changing
the wsa:ReplyTo header (and invoking and asynchronous service)
when
invoking
a service??? Or is it possible at all?
Btw. my configuration is:
apache ode 1.3.2
the webservice I am invoking is running on apache axis 1.4
Thank you guys in advance.
Filip
--
Mark Ford
MIT Lincoln Laboratory
244 Wood Street
Lexington MA 02420
(781) 981-1843
--
Håkon Sagehaug, Scientific Programmer
Parallab, Bergen Center for Computational Science (BCCS)
UNIFOB AS (University of Bergen Research Company)
