Why REST APIs exist - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to show why REST APIs are useful for communication between systems.

Rest API

A REST API allows different systems to [1] data over the internet.

Drag options to blanks, or click blank then click option'

Ahide

Bexchange

Cdelete

Dignore

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing words that mean stopping or hiding data.

REST APIs enable systems to exchange data easily and clearly.

2fill in blank

medium

Complete the code to explain how REST APIs use HTTP methods.

Rest API

REST APIs use HTTP methods like GET and POST to [1] actions on resources.

Drag options to blanks, or click blank then click option'

Aignore

Bblock

Cperform

Ddelay

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing words that mean stopping or not doing anything.

HTTP methods tell the API what action to perform on data.

3fill in blank

hard

Fix the error in the sentence explaining REST API benefits.

Rest API

REST APIs help systems to [1] data in a way that is platform dependent.

Drag options to blanks, or click blank then click option'

Aexchange

Bstore

Cignore

Dsend

Attempts:

3 left

💡 Hint

Common Mistakes

Saying REST APIs are platform dependent.

REST APIs allow data exchange that is platform independent, meaning it works across different systems.

4fill in blank

hard

Fill both blanks to complete the dictionary comprehension explaining REST API data filtering.

Rest API

filtered_data = {item: data[item] for item in data if data[item] [1] [2]

Drag options to blanks, or click blank then click option'

A>

B10

C<

D5

Attempts:

3 left

💡 Hint

Common Mistakes

Using the wrong comparison operator or number.

This code filters data items where the value is greater than 10.

5fill in blank

hard

Fill all three blanks to complete the dictionary comprehension that creates a new dictionary with uppercase keys and values greater than 5.

Rest API

result = [1]: [2] for [3], [2] in data.items() if [2] > 5

Drag options to blanks, or click blank then click option'

Akey.upper()

Bvalue

Ckey

Ditem

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong variable names or not converting keys to uppercase.

This comprehension creates a dictionary with keys in uppercase and includes only items with values greater than 5.

Practice

1. Why do REST APIs exist in software development?

easy

A. To allow different programs to communicate over the internet using simple rules

B. To create complex user interfaces for websites

C. To store data only on local machines

D. To replace all programming languages with one standard

Solution

1. Step 1: Understand the purpose of REST APIs

   REST APIs are designed to let different software programs talk to each other over the internet easily.

2. Step 2: Compare options with this purpose

   Only To allow different programs to communicate over the internet using simple rules correctly describes this purpose. Options A, B, and C do not relate to REST APIs' main goal.

3. Final Answer:

   To allow different programs to communicate over the internet using simple rules -> Option A

4. Quick Check:

   REST APIs exist for communication = D [OK]

Hint: REST APIs help programs talk over the internet simply [OK]

Common Mistakes:

• Thinking REST APIs create user interfaces
• Believing REST APIs store data locally only
• Assuming REST APIs replace programming languages

2. Which HTTP method is commonly used in REST APIs to retrieve data from a server?

easy

A. GET

B. POST

C. DELETE

D. PUT

Solution

1. Step 1: Recall HTTP methods in REST APIs

   GET is the method used to request and retrieve data from a server.

2. Step 2: Match the method to the action

   POST sends data, DELETE removes data, PUT updates data. Only GET retrieves data.

3. Final Answer:

   GET -> Option A

4. Quick Check:

   Retrieve data = GET [OK]

Hint: GET means get data from server in REST APIs [OK]

Common Mistakes:

• Confusing POST with GET for data retrieval
• Using DELETE or PUT to get data
• Not knowing HTTP method purposes

3. What will be the output of this REST API call?

GET /users/123

Assuming user 123 exists and the API returns JSON data.

medium

A. 500 Internal Server Error

B. {"id":123,"name":"Alice"}

C. 404 Not Found

D. {"error":"User not found"}

Solution

1. Step 1: Understand the GET request to /users/123

   This request asks the server for data about user with ID 123.

2. Step 2: Check the condition given

   The user 123 exists, so the server returns the user's data in JSON format.

3. Final Answer:

   {"id":123,"name":"Alice"} -> Option B

4. Quick Check:

   Existing user GET returns data = C [OK]

Hint: GET existing user returns JSON data, not error [OK]

Common Mistakes:

• Choosing error responses when user exists
• Confusing 404 with successful data return
• Not recognizing JSON format

4. Identify the error in this REST API usage:

POST /users/123

What is wrong if the goal is to update user 123's data?

medium

A. The URL should not include the user ID

B. GET method should be used to update data

C. POST is used instead of PUT for updating existing data

D. DELETE method is required to update data

Solution

1. Step 1: Understand HTTP methods for REST APIs

   POST is usually for creating new data, PUT is for updating existing data.

2. Step 2: Match method to action

   Since the goal is to update user 123, PUT should be used instead of POST.

3. Final Answer:

   POST is used instead of PUT for updating existing data -> Option C

4. Quick Check:

   Update needs PUT, not POST = B [OK]

Hint: Use PUT to update existing data, not POST [OK]

Common Mistakes:

• Using POST to update instead of PUT
• Thinking GET updates data
• Believing DELETE updates data

5. You want to design a REST API that allows clients to list all products and add new products. Which HTTP methods and URLs should you use?

hard

A. DELETE /products to list, PUT /products to add new

B. POST /products to list, GET /products to add new

C. PUT /products to list, DELETE /products to add new

D. GET /products to list, POST /products to add new

Solution

1. Step 1: Identify methods for listing and adding

   GET is used to retrieve or list data, POST is used to create or add new data.

2. Step 2: Match methods with URLs

   Both actions use the /products URL; GET lists products, POST adds new products.

3. Final Answer:

   GET /products to list, POST /products to add new -> Option D

4. Quick Check:

   List = GET, Add = POST = A [OK]

Hint: GET lists, POST adds new resources in REST APIs [OK]

Common Mistakes:

• Swapping GET and POST roles
• Using DELETE or PUT incorrectly
• Confusing URLs for different actions