-----Original Message-----
From: Sergey Beryozkin [mailto:[email protected]]
Sent: Mittwoch, 30. Januar 2013 23:46
To: Andrei Shakirin
Cc: [email protected]
Subject: Re: [CXF.REST] Exception mapper on the client in case of Response
retun value
Hi Andrei
On 30/01/13 12:58, Andrei Shakirin wrote:
Hi Sergei,
ExceptionMapper is only used on the server side, on the client side
there's no concept of mapping error responses to custom exceptions
when fluent API is used (standard 2.0, CXF WebClient), so in CXF it
is custom ResponseExceptionMapper provider which can be used by the
proxy client runtime to map an error status code to one of declared
exception classes, for example
Book getBook() throws BookNotFoundException;
CXF client can register ResponseExceptionMapper and convert say 404
to BookNotFoundException;
I have discovered a little bit different behaviour in CXF 2.7.0:
if service interface method returns object - client exception mapper is
invoked, independent if exceptions are declared or not.
Yes - there was a request to support RuntimeException mappers even
without the declared exceptions
If service interface method returns Response, client exception mapper isn't
invoked.
Response response = connectorService.create(connectorTO);
if (response.getStatus() !=
org.apache.http.HttpStatus.SC_CREATED) {
throw (RuntimeException)
clientExceptionMapper.fromResponse(response);
}
Where is this code coming from ?
It is our code from Syncope project. Currently we should manually call
exception mapper on client side for all methods returning Response.
The expectation (consistent with 2.0 client API) is that if Response
is returned then the client needs to handle it itself, including
checking the headers and the status.
Sure, client can do it (see code above), but need additional code for
methods returning Response - looks a little bit ugly for me.
I agree to some extent but more regarding throwing the exceptions - note
Response is meant to represent HTTP response as is but not only 'good'
Response, so if it is in the signature then the client is kind of expected to
handle it.
Do you need checking a client side mapper even for Response for
consistency purposes, example, the application code is expected to
have catch statements whether it is Response or MyCustomType which is
returned from a method ?
Yep, it is the case. Client code expects exceptions, they are coming
automatically from mapper for all methods except returning Response ones
(here we need extra code).
We can get the proxy client side to check the the mappers even if Response
is returned, but only if status is>= 300. So if status is 200 then you'd still
get
no exception if it is not 201 or no Location header is available.
Perhaps it is simpler to simply register a client side JAX-RS 2.0
ClientResponseInterceptor and throw if it is not 201 ?
What do you think ?
Cheers, Sergey
Regards,
Andrei.
-----Original Message-----
From: Sergey Beryozkin [mailto:[email protected]]
Sent: Mittwoch, 30. Januar 2013 12:33
To: [email protected]
Subject: Re: [CXF.REST] Exception mapper on the client in case of
Response retun value
Hi Andrei
On 30/01/13 10:21, Andrei Shakirin wrote:
Hi,
I see that registered ExceptionMapper is not invoked on the client
side, if
service interface returns Response.
Not sure is it JAX-RS specified or desired behaviour.
ExceptionMapper is only used on the server side, on the client side
there's no concept of mapping error responses to custom exceptions
when fluent API is used (standard 2.0, CXF WebClient), so in CXF it
is custom ResponseExceptionMapper provider which can be used by the
proxy client runtime to map an error status code to one of declared
exception classes, for example
Book getBook() throws BookNotFoundException;
CXF client can register ResponseExceptionMapper and convert say 404
to BookNotFoundException;
From one side client has enough information in Response to deal
with
errors.
From other side, if service interface has mix of methods
returning
Response and normal objects, it causes code like this for all "Response"
methods:
Response response = connectorService.create(connectorTO);
if (response.getStatus() !=
org.apache.http.HttpStatus.SC_CREATED) {
throw (RuntimeException)
clientExceptionMapper.fromResponse(response);
}
Where is this code coming from ?
I can imagine that even for methods returning Response, client
exception
mapper is invoked for error response codes.
WDYT?
The expectation (consistent with 2.0 client API) is that if Response
is returned then the client needs to handle it itself, including
checking the headers and the status.
Do you need checking a client side mapper even for Response for
consistency purposes, example, the application code is expected to
have catch statements whether it is Response or MyCustomType which is
returned from a method ?
Cheers, Sergey
Regards,
Andrei.
