Why do we need RESTful Web Services?

Question

I\'m going to learn RESTful web services (it\'s better to say that I\'ll have to do this because it\'s a part of CS master degree program).

I\'ve read some info in

Answer 1

I can safely say I have spent a lot of time to understand this as a beginner but this is the best link to start with REST from scratch! http://www.codeproject.com/Articles/21174/Everything-About-REST-Web-Services-What-and-How-Pa

Just to pull you in,

Think of what a "traditional web service" is. It is an interface with exposed "methods." Clients know the methods' name, input and output and hence can call them.

Now imagine an interface that does not expose "methods". Instead, it exposes "objects". So when a client sees this interface, all it sees is one or more "objects". "An object" has no input and output – because "it does not do anything". It is a noun, not a verb. It is "a thing", not "an action".

For example, think of a traditional web service that provides the current weather conditions if you provide it with a city. It probably has a web method like GetWeatherInfo() which takes a city as input and provides weather data as output. It is easy for you so far to understand how a client will consume this web service.

Now imagine, in the place of the above web service, there is a new one that exposes cities as objects. So, when you look at it as a client, instead of GetWeatherInfo(), you see New York, Dallas, Los Angeles, London and so on. And these cities do not have any application specific methods hanging from them - they are apparently like inert gases - they themselves do not react.

You must be thinking – well, how does that help you, as a client, to get to the weather of Dallas? We will get to that in a few moments.

If all you get from a web service is a "set of objects", obviously you need a way to "act on them". The objects themselves have no methods for you to call, so you need a set of actions that you can apply onto these objects. In other words, you need to "apply a verb to the noun". If you see an object, say, an apple, which is "a noun", you can apply "a verb" like eat, to it. But not all verbs can be applied to all nouns. Like, you can drive a car, but cannot drive a television.

Thus, if a web service exposes only objects, and you are asked – well, let us now design a few standard actions or verbs that "all clients can apply to all objects they see", ...