Developing Applications with SaaS (Software as a Service)

concepcionsockΛογισμικό & κατασκευή λογ/κού

15 Αυγ 2012 (πριν από 5 χρόνια και 3 μέρες)

307 εμφανίσεις

B. RAMAMURTHY



Developing Applications with
SaaS (Software as a Service)

3/16/2013

1

References



http://www.netbeans.org/kb/docs/websvc/zillow.html


Introduction to Web Services
-

NetBeans IDE 6.1
-
6.5

3/16/2013

2

Web services

3/16/2013

3


Web services are components that expose a software
module for use by distributed applications.


The operations offered by a service are usually exposed
using one or more interfaces.


There are two popular programming models available for
interacting with the web services (WS):


REST
-
based.

RE
presentational

S
tate
T
ransfer is a new way to create and
communicate with web services. In REST, resources have URIs and are
manipulated through HTTP header operations. For more details, see
RESTful

Web Services
.


SOAP/WSDL
-
based.

In traditional web service models, web service interfaces
are exposed through WSDL documents (a type of XML), which have URLs.
Subsequent message exchange is in SOAP, another type of XML document. For
more details, see
SOAP
-
based Web Services
.


Software as a Service (SaaS)

3/16/2013

4



SaaS

refers to a software application delivery model where a
software vendor develops a web
-
native software application and
hosts and operates the application for use by its customers over the
Internet.
SaaS

is an increasingly popular model for providing
software functionality as it is economical in terms of both cost and
customer hardware resources.” ref #1 on slide 2


You can be a consumer of
SaaS

or provider/vendor of
SaaS
.


For example, providing a nutritional counseling
SaaS
.


Consuming the
SaaS

provided
Zillow
.


We will work on developing an application that consumes
SaaS

offered by
Zillow
.


“Zillow.com is a Seattle, Washington
-
based online real estate service
company founded in 2005 by Rich Barton and Lloyd
Frink
, former
Microsoft executives and founders of Expedia.”

Steps in SaaS Application Development

3/16/2013

5


Choose the
SaaS

you want to work with.


Register yourself with the vendor: sometimes it is free and other times
you may have to pay for using the
SaaS

(
eg
. Amazon ECS and S3)


Decide on the model for interaction: REST or SOAP. This is not a big
deal if you are using an IDE since IDE like
Netbeans

hides the details of
this model and provides a uniform view.


Create a web application that will consume the
SaaS
.


Create a
servlet

or JSP to insert the web service request.


Drag and drop the web service request, make sure you initialize the
input parameters to the WS.


Build a front
-
end (JSP) so that application can be tested with user
defined parameters.


Build a persistent model for storing any data that may be generated
(this is the database component: we will look at this in a future
presentation.)


Zillow Application

3/16/2013

6


Registering To Receive the
Zillow

API Key


Creating the
Servlet



Adding the
Zillow

GetRegionChart

Operation to the
Servlet



Adding the API Key to the Project


Modifying the
Servlet

to Return the Chart Graphic


Running the
Zillow

Region Chart
Servlet



We will add a JSP as user interface to the above
application so that we can run the application for any
user input.