Service oriented Architecture (SOA)

Hi


http://www.youtube.com/watch?v=0hyXOuvyq2Q&list=TLsaIHJaZiiPY

http://www.youtube.com/user/fourthmonthllc?feature=watch

Basic of SOA

Simple SOA - Mainframe( has data , business logic and UI , graphics )  and dummy terminal .But issue is scalability

Later came the PC where validation can be done by browser , like validating date this is client server .But updation on all the machine became difficult as the 1000 user updation in an office network will be difficult.

then the client/server gave way to 3 tier architecture  A browser a  application server and database server.

Now even will 3 tier architectue it becomes difficult to manage so came teh service oriented architecture

So the db , application service and SAP , oracle

first there were function

then there were object and clasees

issue was .net and java were not able to interact

then people started talking in terms of messages


xml messages.. so messages were standedise

then with it camse services

services are logical encapsulation of self contained
business functionality


services communicates in termsn of messages

-----------------------------
few of points that services should be able to do are

services should be to self define themselves

services should be maintained in repository where we can find them

we should be able to orchestrate services that is
we should be able to design our workflow and plac services in them

consider example of security service and order processing services

we shoud be able to first use security service and then order process
that is check if user is valid and them do order processing

or we shoudl be able to process the order first and then do security check

so the order of service can change

But consider the predominant n-tier development environment in use today -- Java EE:

presentation implemented with JSP/servlets
business logic implemented with POJOs or EJBs
data access logic implemented with JPA/Hibernat

first there were function

then there were object and clasees

issue was .net and java were not able to interact

then people started talking in terms of messages


xml messages.. so messages were standedise

then with it camse services

services are logical encapsulation of self contained
business functionality


services communicates in termsn of messages

-----------------------------
few of points that services should be able to do are

services should be to self define themselves

services should be maintained in repository where we can find them

we should be able to orchestrate services that is
we should be able to design our workflow and plac services in them

consider example of security service and order processing services

we shoud be able to first use security service and then order process
that is check if user is valid and them do order processing

or we shoudl be able to process the order first and then do security check

so the order of service can change

But consider the predominant n-tier development environment in use today -- Java EE:

presentation implemented with JSP/servlets
business logic implemented with POJOs or EJBs
data access logic implemented with JPA/Hibernat

first there were function

then there were object and clasees

issue was .net and java were not able to interact

then people started talking in terms of messages


xml messages.. so messages were standedise

then with it camse services

services are logical encapsulation of self contained
business functionality


services communicates in termsn of messages

-----------------------------
few of points that services should be able to do are

services should be to self define themselves

services should be maintained in repository where we can find them

we should be able to orchestrate services that is
we should be able to design our workflow and plac services in them

consider example of security service and order processing services

we shoud be able to first use security service and then order process
that is check if user is valid and them do order processing

or we shoudl be able to process the order first and then do security check

so the order of service can change

But consider the predominant n-tier development environment in use today -- Java EE:

presentation implemented with JSP/servlets
business logic implemented with POJOs or EJBs
data access logic implemented with JPA/Hibernat

Amazon web sevices alllows for

computer , storage and database services

http://www.youtube.com/watch?v=DERzYnthq1s

what is webservice

we are callign a function which is inside a software from other software
software which gives the call is called client and software which receives the request is called server



both these things can be writen in different languages client can be in .net and server function can be in java

in this the format of input and output messages is important

there is 2 ways a web service can be used either the severs provides WSDL file or there is a UDDI universal description discovery and integration on the internet where all service providers register their service and the whoever want can reach UDDI which will list all similar services with their WSDL file

there are RESTful web services using rest protocol and SOAP web services


RESTful web services are accessed by passing URI from the webserve

server would send teh representation fo that service to client this can be in XML

REST ful webservices uses HTTP. they use 4 main http methods

GET retrieve a resource
POST create a resource
PUT update a resource
DELETE deletes a resource