Web Services

Question 1

website

Answer 1

• a set of globally accessible, interconnected web pages that has a single domain name
• one-way informational feeds, which means their main goal is to present information to the visitors
• e.g. blogs and news

Question 2

web applications

Answer 2

• they allow user to interact with them and connect to a database to make the content dynamic
• they are capable of performing a wide range of functions
• e.g. Twitter and Amazon

Question 3

web service

Answer 3

• a software system communicates between two different sets of devices or application
• it’s not for general users and very unlikely to have any user interfaces
• a service offered by an electronic device to another electronic device, communicating with each other via the internet (World Wide Web)
• a server running on a computer device, listening for requests at a particular port over the network, serving web documents (HTML, JSON, XML, images)
• it can be categorized into two types: REST and SOAP

Question 4

REST

Answer 4

• Representational State Transfer

- an architecture for creating web services

Question 5

REST API

Answer 5

• an application programming interfaces implemented according to REST architecture

Question 6

REST’s Architectural Constraints

Answer 6

• client-server: REST application is expected to have a server to manage data and a client to handle user interactions
• stateless: servers don’t maintain any client state. Each request sent to the server is independent
• cacheable: possible responses should be cached to avoid unnecessary processing
• uniform interface
• layered system

Question 7

constraints

Answer 7

the rules that enforce data integrity on the RDBMS automatically

Question 8

SOAP

Answer 8

• Simple Object Access Protocol
• it was designed by Microsoft in 1998
• it’s an XML-based messaging protocol for transferring information between applications or computers

Question 9

SOAP message

Answer 9

an XML document containing:

• envelope that identifies the XML document as a SOAP message
• header that stores header information (optional)
• body that stores call and response informatioin
• fault that stores information about errors if any errors occurred during the process (optional)

Question 10

SOAP vs REST

Answer 10

• SOAP is a protocol while REST is an architectural style
• SOAP has an official standard while REST has not.
• REST APIs are lightweight and requires less bandwidth
• SOAP uses XML while REST can use several data format like HTML, XML, JSON etc.
• SOAP is language, platform, and transport-independent
• SOAP doesn’t require HTTP while REST does