Representational state transfer (REST) and Simple

Question

Can somebody explain what is REST and what is SOAP in plain english? And how Web Services work?

Answer 1

The problem with SOAP is that it is in conflict with the ideals behind the HTTP stack. Any middleware should be able to work with HTTP requests without understanding the content of the request or response, but for example a regular HTTP caching server won't work with SOAP requests without knowing only which parts of the SOAP content matter for caching. SOAP just uses HTTP as a wrapper for its own communications protocol, like a proxy.

Answer 2

REST is an architecture style for designing networked applications. The idea is that, rather than using complex mechanisms such as CORBA, RPC or SOAP to connect between machines, simple HTTP is used to make calls between machines.

Answer 3

SOAP – "Simple Object Access Protocol"

SOAP is a slight of transferring messages, or little amounts of information over the Internet. SOAP messages are formatted in XML and are typically sent controlling HTTP.

REST – "REpresentational State Transfer"

REST is a rudimentary proceed of eventuality and receiving information between fan and server and it doesn't have unequivocally many standards defined. You can send and accept information as JSON, XML or even plain text. It's light weighted compared to SOAP.

Answer 4

SOAP - Simple Object Access Protocol is a protocol!

REST - REpresentational State Transfer is an architectural style!

SOAP is an XML protocol used to transfer messages, typically over HTTP

REST and SOAP are arguably not mutually exclusive. A RESTful architecture might use HTTP or SOAP or some other communication protocol. REST is optimized for the web and thus HTTP is a perfect choice. HTTP is also the only protocol discussed in Roy Fielding's paper.

Although REST and SOAP are clearly very different, the question does illuminate the fact that REST and HTTP are often used in tandem. This is primarily due to the simplicity of HTTP and its very natural mapping to RESTful principles.

Fundamental REST Principles

Client-Server Communication

Client-server architectures have a very distinct separation of concerns. All applications built in the RESTful style must also be client-server in princple.

Stateless

Each each client request to the server requires that its state be fully represented. The server must be able to completely understand the client request without using any server context or server session state. It follows that all state must be kept on the client. We will discuss stateless representation in more detail later.

Cacheable

Cache constraints may be used, thus enabling response data to to be marked as cacheable or not-cachable. Any data marked as cacheable may be reused as the response to the same subsequent request.

Uniform Interface

All components must interact through a single uniform interface. Because all component interaction occurs via this interface, interaction with different services is very simple. The interface is the same! This also means that implementation changes can be made in isolation. Such changes, will not affect fundamental component interaction because the uniform interface is always unchanged. One disadvantage is that you are stuck with the interface. If an optimization could be provided to a specific service by changing the interface, you are out of luck as REST prohibits this. On the bright side, however, REST is optimized for the web, hence incredible popularity of REST over HTTP!

The above concepts represent defining characteristics of REST and differentiate the REST architecture from other architectures like web services. It is useful to note that a REST service is a web service, but a web service is not necessarily a REST service.

See this blog post on REST Design Principals for more details on REST and the above stated bullets.

Answer 5

SOAP and REST both refer to ways for different systems to talk to each other.

REST does this using techniques that resemble the communication that your browser has with web servers: using GET to request a web page, POSTing in form fields, etc.

SOAP provides for something similar but does everything through sending blocks of XML back and forth. Another key component of SOAP is WSDL which is an XML document that describes what functions and data elements are supported. WSDLs can be used to programmatically "discover" what functions are supported as well as to generate programming code stubs.

Answer 6

I think that this is as easy as I can explain it. Please, anyone is welcome to correct me or add to this.

SOAP is a message format used by disconnected systems (like across the internet) to exchange information / data. It does with XML messages going back and forth.

Web services transmit or receive SOAP messages. They work differently depending on what language they are written in.