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REST Anti-Patterns. When people start trying out REST, they usually start looking around for examples – and not only find a lot of examples that claim to be “RESTful”, or are labeled as a “REST API”, but also dig up a lot of discussions about why a specific service that claims to do REST actually fails to do so. Why does this happen? HTTP is nothing new, but it has been applied in a wide variety of ways. Some of them were in line with the ideas the Web’s designers had in mind, but many were not. Applying REST principles to your HTTP applications, whether you build them for human consumption, for use by another program, or both, means that you do the exact opposite: You try to use the Web “correctly”, or if you object to the idea that one is “right” and one is “wrong”: in a RESTful way. For many, this is indeed a very new approach.

As with any new approach, it helps to be aware of some common patterns. Let’s start with a quick list of anti-patterns I’ve managed to come up with: Sammy. What Sammy is a tiny javascript framework built on top of jQuery. It’s RESTful Evented JavaScript. Why jQuery is probably the fastest, most robust way to abstract basic low-level Javascript functionality that every Javascript developer needs. Working heavily with Sinatra, I realized that the simple route definitions and structure it provided could be a great fit with jQuery/JavaScript.

It is that, I disagree substantially with the assumptions on which these arguments are made. And yet, as I recollect my own thoughts a year ago - a few months post my journey into REST, I realised that there was a time that I did actually believe some of these assumptions. I also realised that it is likely that many others who are dealing with a transition from SOA to REST are also likely to be perhaps sharing similar assumptions.

Without much ado let me quickly get to the central assertion of this blog post. Service orientation is neither essential for, nor is it the intention of REST. There. And it further goes on to state But I digress, let's go back to "services". Service Wikipedia describes a service as follows : Resources You cheated! Welcome | REST-* Calculus -- web-calculus. Calculus This specification defines an application interface model, the web-calculus, that is independent of the application programming model. The model enables reasoning about the functionality and security of an application interface. Abstract The web-calculus is defined over a directed graph. Overview Design goals Access control is expressed through the capability-based security model.

Capability-based security The web-calculus operates on a directed graph. Meta-model Many different application programming models exist, each with its own unique constructs. Partial understanding Many useful applications can operate on a graph using only partial understanding of the nodes in the graph. Interface refactoring Many existing security models operate in terms of statically defined authority bundles. Adapting an application with static authority divisions to a new usage requires the creation of protection proxies. Description The interface model defined by the web-calculus need not be reified.

The Definitive Guide to GET vs POST. I will first provide a brief introduction to REST and then describe how to build Web services in the REST style. What is REST? REST is a term coined by Roy Fielding in his Ph.D. dissertation [1] to describe an architecture style of networked systems. REST is an acronym standing for Representational State Transfer. Why is it called Representational State Transfer? The Web is comprised of resources. Your Web Service Might Not Be RESTful If… REST – a quick summary. I’d read a lot of blogs talking about REST and it’s benefits but I hadn’t fully got it. Whilst on holiday I read RESTful Web Services, which I had seen recommended, in an effort to try and finally grok REST.

I thoroughly recommend this book, it helped me connect a lot of previously separate ideas into a coherent whole. What I hope to do here is give an overview of what I’ve learnt from the book to act as a reference to myself and maybe help other people in the process. Definition REST is short for Representational State Transfer. Distilled down, it’s basically about using the HTTP verbs, GET, POST, PUT, DELETE and HEAD, in order to act on resources, represented by individual URIs.

Resources are similar to what most of you will think of as domain entities. Underlying principle The main idea behind REST is that you are working with the HTTP protocol. The requests and responses of the HTTP protocol consist of a head and a body. HTTP verbs and their meanings POST and PUT REST and HTML forms. Slow REST. We’re working on a fairly substantial revision of the Sun Cloud API, motivated by this problem: In a RESTful context, how do you handle state-changing operations (POST, PUT, DELETE) which have substantial and unpredictable latency?

What we’ve learned, from work with our own back-end based on the Q-layer technology and with some other back-ends, is that Cloud operations are by and large not very fast; and that the latencies show up in weird places. Here’s an example: in our own implementation, creating a Virtual Machine from a template or by copying another VM instance is very snappy. But weirdly, connecting a network (public or private) to a VM can sometimes be extremely slow. Go check out other implementations like EC2 and you see a similar unpredictable-latency narrative. The idiom we’d been using so far was along these lines: There are a few points that are still troubling me, listed here in no particular order: RESTFul Design Patterns. Summarize a set of RESTful design practices that I have used quite successfully. Object PatternsIf there are many objects of the same type, the object URL should contains the id of the object. If this object is a singleton object of that type, the id is not needed.

Get the object representationHTTP GET is used to obtain a representation of the object. HTTP header "Accept" is also used to indicate the expected format. GET /library/books/668102 HTTP/1.1Host: www.xyz.comAccept: application/json Modify an existing ObjectHTTP PUT is used to modify the object, the request body contains the representation of the Object after successful modification. Create a new Object HTTP PUT is also used to create the object if the caller has complete control of assigning the object id, the request body contains the representation of the Object after successful creation. HTTP/1.1 201 Created. Why REST ?

Introduction It is becoming apparent that even as it becomes popular, REST (Representational State Transfer) is not yet as well understood. This might seem a surprising statement, but a lot of us use REST thanks to many frameworks supporting REST like interfaces, have a sense of what REST like interfaces are like (even if such an understanding is not sufficiently accurate), and exercise our common sense in using such interfaces. Having said that, let me clarify that while the internet is full of documentation about the semantics of REST, its actually quite light on the rationale for REST (including Roy Fielding's dissertation which is the reference document for REST). Thus I have had to intersperse REST semantics and historical narrative with some personal opinions. So treat this as a part opinion and feel free to question my thought where you think it does not make sense. Audience If you are a REST expert, you are likely to have figured out much of this any ways by now.

Flow Ho Hum. Email. PUT or POST: The REST of the Story. Web service designers have tried for some time now to correlate CRUD (Create, Retrieve, Update and Delete) semantics with the Representational State Transfer (REST) verbs defined by the HTTP specification–GET, PUT, POST, DELETE, HEAD, etc. So often, developers will try to correlate these two concepts–CRUD and REST–using a one-to-one mapping of verbs from the two spaces, like this: Create = PUTRetrieve = GETUpdate = POSTDelete = DELETE “How to Create a REST Protocol” is an example of a very well-written article about REST, but which makes this faulty assumption. (In fairness to the author, he may well have merely “simplified REST for the masses”, as his article doesn’t specifically state that this mapping is the ONLY valid mapping. And indeed, he makes the statement that the reader should not assume the mapping indicates a direct mapping to SQL operations.) But such a trivial mapping is inaccurate at best. The crux of the issue comes down to a concept known as idempotency.

Analysis. Sammy. What Sammy is a tiny javascript framework built on top of jQuery. It’s RESTful Evented JavaScript. Why jQuery is probably the fastest, most robust way to abstract basic low-level Javascript functionality that every Javascript developer needs. However, it really remains low-level and does not imply any structure or organization for larger scale Javascript applications. Working heavily with Sinatra, I realized that the simple route definitions and structure it provided could be a great fit with jQuery/JavaScript. Not only does it allow you to respond to specific URLs, but utilizing the URL hash (#) you can create single page applications that still respond to the back button in your browser (ala Gmail).

I started off on this project thinking “It would be cool to implement Sinatra in JavaScript”. I see Sammy as a great way to build simple to complex applications built upon RESTful data stores like CouchDB or Cloudkit. Basics A Sammy application revolves around ‘routes’. Var app = $.sammy(...) REST Programming Toolbox Requirements. REST is all the rage, and everybody claims they're doing REST. REST is a style of designing web services, and the question is how this style can be best supported by a programming environment. there are two possible perspectives of this problem. one is the more high-level view of how to best structure code that is built around the assumption of a uniform interface. a popular example for this is JAX-RS, released as JSR-311 last year, and implemented by the Restlet framework. this is not what i want to discuss here. a different perspective is that of basic tools that might be useful for implementing RESTful services (in that case interpreting REST in its narrower sense of web architecture and its use of HTTP and URIs). in a recent blog post, marc hadley reports on Integrating Jersey and Abdera. the interesting thing is how his approach combines a high-level framework (JAX-RS), with more low-level tools for handling HTTP and content (in that case, feeds).

REST worst practices. A few weeks ago, I sent the following in a email to a co-worker asking for input on designing REST APIs in Django. Since then, I’ve quoted myself a few times; I thought these thoughts would be worth a (slightly edited) public home. I think the best way to dive in terms of mistakes to avoid. If you poke around you’ll find a couple-three different stabs at writing a generic REST API module for Django.

So, with no further ado, some REST “worst practices:” Conflating models and resources In the REST world, the resource is key, and it’s really tempting to simply look at a Django model and make a direct link between resources and models – one model, one resource. I’d solve this in a similar manner to the way forms work in Django: there’s a basic Form, and then a ModelForm; I’d have a Resource and a ModelResource. Hardcoded auth (Or depending on cookie-based auth.) Resource-specific output formats The idea is that client code shouldn’t have to know how to parse all sorts of different formats.

Pk11 / pinky / wiki / Home — bitbucket.org. REST for Java developers, Part 4. From an IT manager's perspective, REST might just be another way of moving information, but without all the tools associated with SOAP. In this final article in the REST for Java developers series, Brian Sletten takes on that myth, and several others about REST, by looking at its role in emerging architectures such as the Semantic Web. The move to REST, he says, is not a move away from SOAP, but an embracing of the Web in its entirety, both inside and outside of the enterprise. Level: Intermediate So far in the REST for Java developers series you've learned hands-on about the RESTful way of doing things.

If you're reading this article it's safe to assume you're interested, even excited, about applying REST in your Java-based development. But what about other developers and managers in your shop? If you want to start building RESTful interfaces at work, you need to be able to explain why REST is the basis of future information systems, and why it's worth adopting now. Where are the REST frameworks? I like REST. I’ll admit that I didn’t understand all of Dr. Roy Fielding’s Dissertation (he is, after all writing to experts in the field of API design) but I think that I’ve managed to understand enough of it that Rails’ implementation of REST leaves a lot to be desired.

Rails is not alone, many services are releasing APIs that they are calling REST. Dr. Fielding recently addressed this in a post on his site. Like his thesis, he is talking to API designers, not to Joe and Jane Developer who needs to get the latest web site off the ground. If you read Subbu’s article and compare it to the standard Rails 2.x web application you will quickly see that difference. There is the comparison that most people who think they are writing REST APIs are forgetting; HTTP. No most of us have no need for creating a new REST API. A Note: I’m making a distinction that I don’t think Dr. What about the Frameworks One of the biggest problems is that people are trying to bolt REST onto MVC frameworks.

Zipwire-rest. REST for corporate IT. Jester. HTTP Conversation Codes. The REST Dialogues. RESTful Web Services Development Checklist. Specialization. REST API Design: Invent Media Types, Not Protocols and Understan. Joe Gregorio | BitWorking | An Introduction to REST. REST and Python. RestWiki: Front Page. Fielding Dissertation: CHAPTER 5: Representational State Transfe. Writing a Ruby Client for a RESTful Web Service using Bricklayer. Why REST? REST - The short version. Persevere. oEmbed FAIL! Represent RESTfully. Resourceful Vs Hackable Search URLs. REST Eye for the Relational Guy - The "Uniform Interface&qu. REST: Nouns and Resources. PyMOTW: urllib. MicroBlog " GET, POST, safety, idempotency. Addressing Doubts about REST. How I Explained REST to My Wife.