http://ofbiz.116.s1.nabble.com/Discussion-REST-support-in-OFBiz-tp3497127p3504287.html
REST semantics are in the HTTP headers as well as in the HTTP method.
a create operation, and PUT is an update operation. But I agree with you
> One bit of documentation I like that shows clearly how the RESTful services are defined and what the messages look like is the Adility API docs, such as this one:
>
>
http://apidoc.adility.com/submission-api>
> The nice thing (and actually many RESTful API docs do this) is that they list each "service" for that service they tell you which HTTP method is used, and what the path to the resource is. The point of this style of mapping is because the HTTP methods (GET, PUT, POST, DELETE) don't really map naturally to, well, to anything. They don't even map well to CrUD operations because PUT and POST are really meant for submitting resources and both could technically result in a create or update, though they have different intended uses and semantics that confuse the matter further.
>
> So, it's generally necessary to define service "locations" (and mappings to the actual service) not just as a URL, but with a HTTP method and URL pair.
>
> On a side note, to handle all HTTP methods we'll need to either modify the ControlServlet, or (maybe preferable, and what I've done on other projects) just use a totally separate servlet that is meant for the RESTful API. In other words, because RESTful stuff relies more on lower level HTTP stuff it is quite different from the more generic approach the ControlServlet uses.
>
> -David
>
>
> On May 6, 2011, at 9:39 AM, Adrian Crum wrote:
>
>> Here is the Amazon REST API - it could be a good source of ideas for implementation:
>>
>>
http://docs.amazonwebservices.com/AmazonS3/latest/dev/index.html?RESTAPI.html>>
>> -Adrian
>>
>> On 5/6/2011 7:33 AM, Jacques Le Roux wrote:
>>> After having read the response hyperlinks article I tend to agree with Adrian. HATEOAS seems to me a really important feature of
>>> REST
>>> I have still to read completly the 1st article Adrian mentionned though. I mean
http://www.infoq.com/articles/rest-introduction>>>
>>> And yes I also prefer response-hyperlink instead of hateoas-attributes
>>>
>>> Jacques
>>>
>>> From: "Adrian Crum"<
[hidden email]>
>>>> I don't like the idea of adding attributes to the existing service element because we still need a way to specify response
>>>> hyperlinks (HATEOAS), plus I imagine other sub-elements and additional attributes will be needed as we build it out more.
>>>>
>>>> I prefer to keep the attribute names similar to the names used in the specification - so they will make sense to developers who
>>>> are familiar with REST. I came up with a better name for the hateoas-attributes element: response-hyperlink.
>>>>
>>>> -Adrian
>>>>
>>>> On 5/6/2011 2:23 AM, Jacopo Cappellato wrote:
>>>>> What about adding the "noun" and "verb" attributes to the "service" element?
>>>>> BTW in order to write a good application I suspect that a lot of services should be refactored to better fit into a REST based
>>>>> application.
>>>>> A good candidate for a prototype could be the Webtools' "Entity Data Maintenance" application: we could rewrite it to work with
>>>>> RESTful URIs like
>>>>>
>>>>> webtools/entities/
>>>>> webtools/entities/orderheaders/
>>>>> webtools/entities/orderheaders?orderTypeId=SALES_ORDER
>>>>> webtools/entities/orderheaders/10010 (CRUD using GET/POST/DELETE)
>>>>> webtools/entityrelations/orderheader (this will return URLs of related entities)
>>>>>
>>>>> We could provide different representations for the responses (and this could also serve to reimplement the "XML data export"
>>>>> part).
>>>>>
>>>>> Kind regards,
>>>>>
>>>>> Jacopo
>>>>>
>>>>> On May 5, 2011, at 5:06 PM, Adrian Crum wrote:
>>>>>
>>>>>> I'm thinking we could have a new element for the service definition:
>>>>>>
>>>>>> <service name="createExample" default-entity-name="Example" engine="entity-auto" invoke="create" auth="true">
>>>>>> ...
>>>>>> <rest-attributes resource="example" method="POST"/>
>>>>>> ...
>>>>>> </service>
>>>>>>
>>>>>> The presence of the rest-attributes element implies the service can be exported via REST.
>>>>>>
>>>>>> So, a new Example can be created by sending an HTTP POST request to
>>>>>>
>>>>>>
https://mydomain.com/rest/example>>>>>>
>>>>>> "HATEOAS" can be implemented with child elements:
>>>>>>
>>>>>> <service name="createExample" default-entity-name="Example" engine="entity-auto" invoke="create" auth="true">
>>>>>> ...
>>>>>> <rest-attributes resource="example" method="POST">
>>>>>> <hateoas-attributes resource="exampleItem" .../>
>>>>>> ...
>>>>>> </rest-attributes>
>>>>>> ...
>>>>>> </service>
>>>>>>
>>>>>> <service name="createExampleItem" default-entity-name="ExampleItem" engine="entity-auto" invoke="create" auth="true">
>>>>>> ...
>>>>>> <rest-attributes resource="exampleItem" method="POST">
>>>>>> <hateoas-attributes resource="example" .../>
>>>>>> ...
>>>>>> </rest-attributes>
>>>>>> ...
>>>>>> </service>
>>>>>>
>>>>>> The REST servlet will use the hateoas-attributes elements to construct URLs for the REST response.
>>>>>>
>>>>>> What do you think?
>>>>>>
>>>>>> -Adrian
>>>>>>
>>>>>> On 5/4/2011 6:24 PM, Adrian Crum wrote:
>>>>>>> Thanks Scott!
>>>>>>>
>>>>>>> I agree - the REST URLs (or URIs) should represent resources and the HTTP commands should represent actions taken on those
>>>>>>> resources. I guess I was trying to take a shortcut by having REST URLs point directly to OFBiz services.
>>>>>>>
>>>>>>> So we need a way to map REST URLs to the appropriate services. Maybe the service definitions could include a REST resource
>>>>>>> identifier. That should be easy to implement.
>>>>>>>
>>>>>>> How could we implement something like the "Link things together" section of this article:
>>>>>>>
>>>>>>>
http://www.infoq.com/articles/rest-introduction>>>>>>>
>>>>>>> (That question is for the community, not Scott specifically).
>>>>>>>
>>>>>>> -Adrian
>>>>>>>
>>>>>>>
>>>>>>> On 5/4/2011 5:54 PM, Scott Gray wrote:
>>>>>>>> Hi Adrian
>>>>>>>>
>>>>>>>> My limited understanding is that RESTful URLs should point to a data resource rather than service logic resources. The verbs
>>>>>>>> (HTTP request method) are used to indicate the type of operation (CRUD) to be performed on the noun (data object). So you'd
>>>>>>>> have something like a URL that points to say the "person" resource and using that URL you can GET a person(s), create or
>>>>>>>> update (POST) a person(s) and DELETE a person.
>>>>>>>>
>>>>>>>> If what I say above is correct then what OFBiz lacks primarily is the ability to map a verb and nouns combination to a
>>>>>>>> specific service. I believe David has taken some steps to resolving that in Moqui which we could achieve by altering the way
>>>>>>>> we define services or alternatively as a stop-gap measure we could introduce an additional mapping layer which defines
>>>>>>>> resource end-points and maps the request type to the appropriate service (perhaps not so easy for POST operations that use a
>>>>>>>> create or update approach but possible by checking for the presence of specific record identifying parameters to indicate an
>>>>>>>> update).
>>>>>>>>
>>>>>>>> What you've described below sounds more like a regular HTTP web service approach that just makes a bit more use of the request
>>>>>>>> headers than we do currently.
>>>>>>>>
>>>>>>>> Regards
>>>>>>>> Scott
>>>>>>>>
>>>>>>>> HotWax Media
>>>>>>>>
http://www.hotwaxmedia.com>>>>>>>>
>>>>>>>> On 5/05/2011, at 12:11 PM, Adrian Crum wrote:
>>>>>>>>
>>>>>>>>> I'm working on a project that might require accessing OFBiz services via REST. I know there have been discussions about using
>>>>>>>>> Axis, and Chris Snow was able to get a REST library to work with OFBiz. Please correct me if I'm wrong, but it seems to me
>>>>>>>>> OFBiz already has most of what is needed to implement REST, so there shouldn't be any need to use any additional libraries.
>>>>>>>>>
>>>>>>>>> From what I understand, REST services are simply HTTP requests sent to a particular URL to invoke a particular service. The
>>>>>>>>> request response contains any requested data in a format the REST client specified in the request. The HTTP commands GET,
>>>>>>>>> POST, PUT, and DELETE are used in the requests. The meaning of the REST HTTP commands are server-specific.
>>>>>>>>>
>>>>>>>>> So here is what I'm thinking: Let's say we want to access OFBiz services via REST. We don't need to support the PUT and
>>>>>>>>> DELETE commands because the services themselves determine what actions will be performed on the data. So, let's say that a
>>>>>>>>> GET command gets information about the service, and the POST command invokes the service.
>>>>>>>>>
>>>>>>>>> From my perspective, this could be implemented in two different ways: a REST servlet or a REST view handler. In either case,
>>>>>>>>> the basic flow would be something like:
>>>>>>>>>
>>>>>>>>> 1. Get service name from request URL, look up service model. If export is false, return 404.
>>>>>>>>> 2. If service model auth is true, get credentials from HTTP header. If no credentials, return 401. If credentials are found,
>>>>>>>>> attempt to log in user. If login fails, return 401.
>>>>>>>>> 3. If command is GET, get Accept content type(s) from HTTP header, use those to find a converter. Convert service model info
>>>>>>>>> to requested type and put it in the response.
>>>>>>>>> 4. If command is POST, get content type from HTTP header, use that to find a converter. Convert POST data to service
>>>>>>>>> parameters and invoke the service. Get Accept content type(s) from HTTP header, use those to find a converter. Convert
>>>>>>>>> service result to requested type and put it in the response.
>>>>>>>>>
>>>>>>>>> So, we could implement REST with existing artifacts - no additional libraries are needed (except maybe for data conversions).
>>>>>>>>>
>>>>>>>>> What do you think? I'm not a REST expert, so comments are welcome!
>>>>>>>>>
>>>>>>>>> -Adrian
>>>>>>>>>
>>>