What is the meaning of client in SOA?

Question

In service oriented architecture, multiple components are connected through the standard interface define in system, and they hides impelemention details. and client consumes the service so i confused about clients, are they directly request from web browser or called from presentation layer in web ?

ex:- what i think about SOA

Database --- > Service ---->(interface like REST, SOAP or Thrift) Consumer

so here consumer can be direct web client ?

1. Database (mysql) --> Service (Java Restful) ---> Webserver(.php)-----> Browser

2. Database (mysql) --> Service (JavaRestful) --> Browser(api call though ajax)

so which is answer ?

if first is the answer then will not it be slow, mean we are adding 1 layer more that mean more remote calls mean slow, right ?

Answer 1

SOA is not about specifying how things should be done, SOA is just a core set of principles The four tenets of SOA which when followed should in theory help the integration of multiple services in middleware architecture.

One thing to note that, you should never expose your services directly, you should hide them behind a web interface (gateway), but in fairness, your example isn't really a SOA architecture, it seems to me that is is just some Web Interface which exposes some web endpoints.

That said, both your approaches are valid.