Archives

Archives / 2008 / November
  • My durable WCF RESTful calculator

    A durable service in WCF is by a definition a service that can persist all its internal state across calls in some durable storage. For every operation, the service state is retrieved from the storage, the operation is executed and finally the state is persisted again in the storage. Therefore, there is not need to keep the service instance idle in memory while waiting for client calls. It is equivalent to a long run session, which make this feature something ideal for long-running processes like workflows (In fact, workflow services are mount on top of this feature),

  • Open Source alternatives in .NET for building RESTful services

    Usually all my posts about REST are about WCF or mention this technology in some parts. Today, I decided to take a different approach and discuss some of the projects available today for building REST services,  Resourceful and Dream framework (Both available for mono as well).
    It is worth mentioning however that the WCF team has made an excellent work introducing the new Web Model in .NET 3.5, it has definitively helped a lot to adopt this kind of service in the .NET platform. In my opinion, there are still some aspects in WCF that could be improved,

  • OAuth channel for WCF RESTful services

    While OpenID and WS-Federation focus on delegating user identity (or a collection of identity claims), OAuth was designed to address a different and complementary scenario, the delegation of user authorization. In few words, OAuth allows a client application to obtain user consent (as access tokens) for executing operations over private resources on his behalf.

  • Routing to the right workflow service instance through URI templates (REST workflows part III)

    Continuing from my previous posts "REST and Workflow services play well together I" and "REST and Workflow services play well together II", in which I created a new binding to send the workflow context as an http header, I've applied some modifications to that sample to support also routing through URI templates. This is very helpful for scenarios where client applications are not necessarily aware of the existence of a workflow services on the other end, so the context information is reconstructed from the resource URI using Uri templates.

  • Conditional Puts in REST

    Conditional puts is a technique generally used in a REST architecture to inform clients about possible conflicts when multiple updates are performed simultaneously over the same resource version. It basically works as fist-write / first-win approach, a client can only commit an operation only if the underline resource has not changed in the meanwhile, otherwise it may receive a http conflict error.