On 07 Nov 2013, at 17:46, cowwoc <cowwoc_at_bbs.darktech.org> wrote:
> On 07/11/2013 11:16 AM, Marek Potociar wrote:
>>
>> On 07 Nov 2013, at 16:41, cowwoc <cowwoc_at_bbs.darktech.org> wrote:
>>
>>> Hi Marek,
>>>
>>> Are you proposing adding the necessary API methods but throwing RuntimeExceptions unless some flag is set? I would support this approach, although in practice I don't think you'll need such a flag because we're talking about legal requests. Whether a request is "legal but non-sense" is a subjective matter.
>>
>> What I'm thinking is to make a flag (which could be by default enabled in the Jersey test client and) that would make sure Jersey is not trying to remove any headers. (Even though in this case I think we have a different problem - look at the post(...) method javadoc and the sentece about overwriting Content-* headers; there is also a related bug filed on that already, IIRC).
>
> I see the problem (Content-* headers) but perhaps we can exploit a hole in the specification. If the entity does not provide a Content-Type then there is nothing to set, hence no overwriting takes place.
>
> PS: I couldn't find the relevant bug report. Where is it?
Sorry, it was just a discussion on this mailing list and stackowerflow. I have then started a follow-up discussion on the subject in the JAX-RS Expert Group.
>
>>
>>> To prove my point, I'll provide you with specific examples for the use-cases I was inquiring about:
>>> POST with a Content-Type but no body
>>> When a parent resource may be used to create different kinds of child resources, the Content-Type is used to specify which kind of resource to create.
>> That is not very RESTful. Representation should not drive the resource "type".
>
> Where does it say that?
Resource should represent a concept, not a particular representation of a concept. Resource should be identified by URI (or new content), not by content-type.
>>>
>>> Example
>>> Create a new "terminal" by invoking POST /companies/5 with Content-Type: application/vnd.company.terminal
>>> Create a new "expense report" by invoking POST /companies/5 with Content-Type: application/vnd.company.expense-report
>> Yuck! I certainly would not want to support the above, or make it any easier to support that. If you want to create new resources like this, you should better design a separate "collection" URIs for that - /companies/5/teminals , /companies/5/expense-reports
>
> I think I can make this change, but I don't think it's right for Jersey to be opinionated. The REST community has many different opinions on the "right way" of doing things. If we're going to start eliminating functionality based on individual opinions we're going to anger a lot of users.
We do not eliminate. Our mission, though, is to provide hight-level API that helps you design and implement your services according to the principles of REST (See JSR-311, section 2.1). As such, we are not going to make it simpler for anyone to do ugly stuff. One can use directly lower-level Servlet API if wants to do something non-RESTful with HTTP.
>>> POST without either a Content-Type or body
>>> Used to insert a new element into a collection (there is no confusion about the kind of child resource being created).
>>> Example: Create a new "transaction" by invoking POST /transactions: http://stackoverflow.com/a/147299/14731
>> This is doable, right?
>
> I'm not sure. Are you expecting me to pass null into entity or MediaType in this method? https://jersey.java.net/apidocs/snapshot/jersey/javax/ws/rs/client/Entity.html#entity(T, javax.ws.rs.core.MediaType) If so, the Javadoc should really mention that passing null is an acceptable way to omit the field.
Passing null should work.
Marek
>
> Thanks,
> Gili