Volume 2 - Chapter 23: Understanding REST and JSON

Question 1

What are the 6 attributes of a REST-Based (RESTful) API?

Answer 1

1. Client/Server architecture
2. Stateless operation
3. Client statement of cacheable/uncacheable
4. Uniform interface
5. Layered
6. Code-on-demand

Question 2

True or False:

HTTP is required for an API to be considered RESTful.

Answer 2

False; while HTTP/HTTPS is common, it is not a requirement for an API to be considered RESTful.

Question 3

Describe how the client/server model functions with a RESTful API.

Answer 3

1. A REST client makes an API REST call to the REST server
2. The REST server returns a response to the client

Question 4

Describe how a stateless operation works with a RESTful API.

Answer 4

APIs that are considered RESTful are stateless; they do not track or keep information about previous API calls or request.

REST servers do not make decisions based on previous requests.

Question 5

How does the function of “cacheable/uncacheable” content fit in with RESTful APIs?

Answer 5

1. REST APIs must clearly mark content as cacheable or uncacheable
2. If cacheable, a clear timer must be established for when the content needs to be downloaded again

Question 6

In regards to Python and other scripting languages, describe the difference between a list and a dictionary.

Answer 6

A list is a list of multiple values

A dictionary is a list of matching key:value pairs

Question 7

The following diagram is an example of a ____.

Answer 7

Dictionary, that contains multiple key:value pairs.

Question 8

The following diagram is an example of a ____.

Answer 8

List

Question 9

What are the 4 primary functions that can be performed by an application?

Answer 9

CRUD:
* Create: Create new variables and data structures on a server
* Read: Read existing varialbes and data structures on a server
* Update: Update existing variables and data structures on a server
* Delete: Delete existing varialbes and data structures on a server

Question 10

What is the REST HTTP equivilent to a CRUD “Create” function?

Answer 10

POST

Question 11

What is the REST HTTP equivilent to a CRUD “Read” function?

Answer 11

GET

Question 12

What is the REST HTTP equivilent to a CRUD “Update” function?

Answer 12

PATCH, or PUT

Question 13

What is the REST HTTP equivilent to a CRUD “Delete” function?

Answer 13

DELETE

Question 14

What term best describes the following?

A resource that an HTTP request will act on.

Answer 14

A Uniform Resource Indicator (URI).

Question 15

In regards to a REST GET Request, what part of a URI structure indicates the transport protocol used to transfer the requested data?

Answer 15

The Scheme (Protocol)

For example: https:// or http://

Question 16

In regards to a REST GET Request, what part of a URI structure indicates the destination device that is hosting the requested data?

Answer 16

The Authority (Host:Port)

For example: 192.168.50.2:875

Question 17

In regards to a REST GET Request, what part of a URI structure identifies the data, and its location on the device that is hosting it?

Answer 17

The Path (Resource)

For example: /root/etc/myfiles/notes.txt

Question 18

In regards to a REST GET Request, what part of a URI structure identifies optional parameters for the request used for identifying variables?

Answer 18

The Query (Parameter)

For example: ?parm1=192.168.30.2

Question 19

The following image is an example of a?

Answer 19

JSON output from a REST API call.

Question 20

What term best describes the following?

A technique used to represent variables as text, send them over a network, or store them in a file.

Answer 20

Data Serialization Languages

Question 21

JSON Stands for?

Answer 21

JavaScript Object Notation.

Question 22

XML stands for?

Answer 22

eXtensible Markup Language.

Question 23

The following image is an example of a?

Answer 23

XML output from a REST API call.

Question 24

A technician uses a rest API to request information from a wireless controller. The technician expects to get the following key-value pairs for a dictionary called “statistics”:
* Number of Errors: 482
* Controller Uptime in Days: 399
* Device Hostname: CNTRL-WLC

How would the format of the output of this dictionary be if using XML? (Roughly)

Answer 24

        <root>
             <statistics>
                  <errornum>482</errornum>
                  <uptime>399</uptime>
                  <hostname>CNTRL-WLC</hostname>
             </statistics>
        </root>

Question 25

The following image is an example of a?

Answer 25

Output from a YAML REST API call

Question 26

YAML stands for?

Answer 26

YAML Ain't Markup Language.

Question 27

What is the main difference between YAML and XML in regards to data presentation?

Answer 27

YAML does not provide/define markup details, while XML does.

Question 28

A technician uses a rest API to request information from a wireless controller. The technician expects to get the following key-value pairs for a dictionary called "auth": * Host IP: 10.10.20.20 * Username: myuser * Password: mypass How would the format of the output of this dictionary be if using YAML? (Roughly)

Answer 28

``` vars: auth: host: "{{ 10.10.20.20 }}" username: "{{ myuser }}" password: "{{ mypass }}" ```

Question 29

Which data model language best matches the following? A language that is only used for general data modeling?

Answer 29

YAML.

Question 30

Which data model language best matches the following? A language that is used for general data modeling and serialization?

Answer 30

JSON.

Question 31

Which data model language best matches the following? A language that is used for test markup and data modeling

Answer 31

XML

Question 32

What would be the correct JSON formatting for an object that has 3 string key-value pairs? * address1 is 123 4th St * address2 is 456 6th St * addresss is 789 10th St.

Answer 32

``` { "address1": "123 4th St", "address2": "456 6th St", "address3": "789 10th St" } ```

Question 33

Identify the problem with the following JSON dictonary: ``` { "country1": "canada" "country2": "america" "country3": "sweden" } ```

Answer 33

The key:value pairs for country 1 & 2 are missing a comma. The correct formating is: ``` { "country1": "canada", "country2": "america", "country3": "sweden" } ```

Question 34

What would be the correct JSON formatting for an object that has 3 number key-value pairs? * num1 is 295 * num2 is 3 * num3 is 1001

Answer 34

``` { "num1": 295, "num2": 3, "num3": 101 } ```

Question 35

What would be the correct JSON formatting for an array that has 3 string values? * Germany * Britain * Canada

Answer 35

. ``` [ "Germany", "Britain", "Canada" ] ```

Question 36

Identify the problem with the following JSON array: ``` { "do it faster" "makes us stronger" "somebody" } ```

Answer 36

There are 2 problems with this output. The array should use square brackets, not curly brackets, and there is no comma between entries. The correct output would be: ``` [ "do it faster", "makes us stronger", "somebody" ] ```

Question 37

What would be the correct JSON formatting for an object with 2 arrays that match the following? favfoods: chocolate, banana, and redgrapes favnums: 95, 1111, and 1337

Answer 37

. ``` { "favfoods": [ "chocolate", "banana", "redgrapes" ] "favnums": [ 96, 1111, 1337 ] } ```

Question 38

In JSON, the opening and closing curly brackets {} represent a(n) ____ whereas the square brackets [] represent a(n) ____

Answer 38

In JSON, the opening and closing curly brackets {} represent a(n) **object** whereas the square brackets [] represent a(n) **array**

Question 39

What would be the correct JSON formatting for an object with 2 objects that match the following? myscores: * math=79 * science=93 * english=66 teachers: * math=ashley * science=trevor * english=ramone

Answer 39

. ``` { "myscores": { "math": 79, "science": 93, "english": 66 } "teachers": { "math": "ashley", "science": "trevor", "english": "ramone" } } ```

Question 40

Identify the problem with the following JSON object: . ``` [ "myscores": { "math": 79, "science": 93, "english": 66 } "teachers": { "math": ashley, "science": trevor, "english": ramone } ] ```

Answer 40

There are 2 problems with the example: 1. The outter brackets should be curly, as the example is an object 2. The names of the teachers under the "teachers" object should have quotes The correct output is: ``` { "myscores": { "math": 79, "science": 93, "english": 66 } "teachers": { "math": "ashley", "science": "trevor", "english": "ramone" } } ```

Question 41

True or False: JSON does not store whitespace in its code.

Answer 41

True, when JSON code is stored in a file or sent over a network it does not include whitespace.