Lesson 2 (REST Backend)

Question 1

What does REST stand for?

Answer 1

Representional state transfer

Question 2

What is REST?

Answer 2

A style of software architecture. A collection of architecture principles which outline how resources are defined and addressed.

Question 3

What charactericstics are covered by REST? (3)

Answer 3

URI (uniform resource locator)
HTTP protocol
Make a request and receive a response

Question 4

What are the HTTP protocol methods that are used by REST?

Answer 4

POST, GET, PUT, DELETE

Question 5

is REST A standard?

Answer 5

No, but it used various standars from HTTP and other headers like content/mime types.

Question 6

What formats can a REST representation be and is it constrained?

Answer 6

XML and JSON are most common. Yes this is constrained.

Question 7

What is an example of an URI and is it constrained?

Answer 7

http://example.com/users/1234. Not standard, free to implement. In URL is possible but also as URL parameter.

Question 8

Name the 6 characteristics of REST

Answer 8

1. Uniform interface to send requests to.
2. Decoupled client-server interaction. Same reasons as stateless.
3. Stateless (nothing stored in communication. Each request contains all information that is required.) This is less load and easier to replace the backend.
4. Cacheable
5. Layered (scalability and enforcement of security
6. Extensible through code on demand (code modification through backend)

Question 9

How is a header attribute formatted?

Answer 9

Content-Type: application/json

Question 10

What is the format of an HTTP request?

Answer 10

METHOD /ur/ HTTP/version
Host: domain
Header fields.

Request body

Example:
POST /test/demo_form.asp HTTP/1.1
Host: w3schools.com
name1=value1&name2=value2

Question 11

What options do you have to implement REST in a Java based backend?

Answer 11

Plain servlet (java code)
External libraries like Jersey. A boilerplate for rest based software.

Question 12

Where does SOAP stand for and what is it?

Answer 12

Simple Object Access Protocol A protocol like REST but the based on HTTP requests and using XML message format (only XML)

Question 13

What does WSDL mean and what does it do?

Answer 13

Web Service Description Language. Describes the SOAP functionality on a backend. This is written in XML and can be generated. Can be read by humans but also interpreted by programs.

Question 14

What is BAAS and MBAAS?

Answer 14

(mobile backend as a service) A very popular solution for out of the box and scalable data storage API for mobile apps.

Question 15

What are some features that MBAAS solutions can offer?

Answer 15

Database storage
File storage
User management
Social Network integration
Push notifications
Secure conection
Error &  performance monitoring
Ability to auto generate rest-based interfaces to read and write data

Question 16

What are some MBAAS solutions?

Answer 16

Parse, App42, Senchia IO, Cloudmine & Stackmob

Question 17

What is the difference btween cloud MBAAS and open source MBAAS?

Answer 17

Cloud usually costs money but is easier to use. Other than that is there are alot of enterprise options and there is support. Which is not really for open source.

Question 18

What are samples of open source MBAAS solutions?

Answer 18

Helios, BaasBox, OpenKit.

Question 19

Which REST command can be used to update a resource?

Answer 19

PUT method (as in HTTP)

Question 20

Give two type of representations of resources that are frequently used with REST.

Answer 20

XML and JSON

Question 21

What is meant by the phrase “REST is stateless”?

Answer 21

There is no data saved in the traffic from client-server. Its one request. Everything is a standalone request. Works perfectly since HTTP is also stateless.