Example requests and responses in Rest API - Mini Project: Build & Apply

Example requests and responses

📖 Scenario: You are learning how to work with REST APIs by creating example requests and responses in Python.

🎯 Goal: Build a simple Python script that shows an example GET request and its expected JSON response.

📋 What You'll Learn

Create a dictionary representing the JSON response from an API

Create a string variable representing the example GET request URL

Print the example request and the JSON response

💡 Why This Matters

🌍 Real World

Developers often write example requests and responses to document APIs or test them.

💼 Career

Understanding how to format and display API requests and responses is important for backend and frontend developers.

1

Create example JSON response data

Create a dictionary called response_data with these exact entries: 'userId': 1, 'id': 101, 'title': 'Learn REST APIs', 'completed': false

Rest API

# Create the dictionary response_data with the given entries
# Your code here

Hint

Use curly braces {} to create a dictionary with the exact keys and values.

2

Create example GET request URL

Create a string variable called example_request and set it to the exact value 'GET /todos/101 HTTP/1.1'

Rest API

response_data = {'userId': 1, 'id': 101, 'title': 'Learn REST APIs', 'completed': False}
# Create the string example_request with the exact GET request
# Your code here

Hint

Use quotes to create a string exactly as shown.

3

Prepare output strings

Create a string variable called response_json that converts response_data to a JSON string using import json and json.dumps()

Rest API

response_data = {'userId': 1, 'id': 101, 'title': 'Learn REST APIs', 'completed': False}
example_request = 'GET /todos/101 HTTP/1.1'
# Import json and convert response_data to JSON string in response_json
# Your code here

Hint

Use import json at the top and then json.dumps() to convert the dictionary.

4

Print example request and response

Print the example_request string and then print the response_json string on separate lines

Rest API

import json
response_data = {'userId': 1, 'id': 101, 'title': 'Learn REST APIs', 'completed': False}
example_request = 'GET /todos/101 HTTP/1.1'
response_json = json.dumps(response_data)
# Print example_request and response_json on separate lines
# Your code here

Hint

Use two print statements, one for the request and one for the JSON response.

Practice

1.

What is the main purpose of an example request in a REST API?

GET /users/123

easy

A. To list all possible API endpoints

B. To display the server's internal code

C. To describe the server's hardware

D. To show how to ask the server for specific data or action

Solution

1. Step 1: Understand what a request does

   A request is how a client asks a server for data or to perform an action.

2. Step 2: Identify the role of example requests

   Example requests show exactly how to ask the server, like which URL and method to use.

3. Final Answer:

   To show how to ask the server for specific data or action -> Option D

4. Quick Check:

   Example request = How to ask server [OK]

Hint: Example requests show how to ask the server clearly [OK]

Common Mistakes:

• Confusing requests with server code
• Thinking examples list all endpoints
• Mixing requests with server hardware info

2.

Which of the following is the correct syntax for a simple GET request example in REST API?

easy

A. GET /api/items HTTP/1.1\nHost: example.com

B. POST /api/items HTTP/1.1\nHost: example.com

C. FETCH /api/items HTTP/1.1\nHost: example.com

D. SEND /api/items HTTP/1.1\nHost: example.com

Solution

1. Step 1: Identify the HTTP method for retrieving data

   GET is the standard method to request data from a server.

2. Step 2: Check the syntax of the request line

   The correct format is "GET /path HTTP/1.1" followed by headers like Host.

3. Final Answer:

   GET /api/items HTTP/1.1\nHost: example.com -> Option A

4. Quick Check:

   GET method + correct syntax = GET /api/items HTTP/1.1\nHost: example.com [OK]

Hint: GET requests retrieve data; syntax starts with GET /path HTTP/1.1 [OK]

Common Mistakes:

• Using POST instead of GET for data retrieval
• Using non-standard methods like FETCH or SEND
• Incorrect request line format

3.

Given this example response from a REST API:

{
  "id": 101,
  "name": "Alice",
  "active": true
}

What is the value of the active field?

medium

A. false

B. true

C. "true" (string)

D. null

Solution

1. Step 1: Read the JSON response carefully

   The response shows "active": true without quotes, meaning a boolean true value.

2. Step 2: Understand JSON data types

   Boolean true is a logical value, not a string or null.

3. Final Answer:

   true -> Option B

4. Quick Check:

   Boolean true in JSON = true [OK]

Hint: True without quotes means boolean true, not string [OK]

Common Mistakes:

• Confusing boolean true with string "true"
• Choosing false or null by mistake
• Ignoring JSON syntax rules

4.

Look at this example request and response pair:

Request: POST /api/login HTTP/1.1\nHost: example.com\nContent-Type: application/json\n\n{"username": "user", "password": "pass"}

Response: 404 Not Found

What is the most likely error in the example?

medium

A. The URL path is incorrect or missing

B. The HTTP method POST is invalid

C. The Content-Type header is wrong

D. The JSON body is malformed

Solution

1. Step 1: Understand 404 Not Found meaning

   404 means the server did not find the requested URL path.

2. Step 2: Check the request details

   POST and Content-Type look correct; JSON body is valid. So the path is likely wrong or missing.

3. Final Answer:

   The URL path is incorrect or missing -> Option A

4. Quick Check:

   404 error = wrong URL path [OK]

Hint: 404 means URL path not found, check request URL [OK]

Common Mistakes:

• Thinking 404 means bad JSON or headers
• Assuming POST method is invalid
• Ignoring the URL path correctness

5.

You want to create an example response for a REST API that returns a list of products with their id and price. Which JSON response below correctly shows two products?

hard

A. [{"id": 1, "price": "9.99"}, {"id": 2, "price": "19.99"}]

B. {"id": 1, "price": 9.99, "id": 2, "price": 19.99}

C. [{"id": 1, "price": 9.99}, {"id": 2, "price": 19.99}]

D. {"products": {"id": 1, "price": 9.99}, {"id": 2, "price": 19.99}}

Solution

1. Step 1: Identify correct JSON array format

   A list of products should be an array (square brackets) containing objects for each product.

2. Step 2: Check each option's JSON structure

   [{"id": 1, "price": 9.99}, {"id": 2, "price": 19.99}] is a valid JSON array with two objects, each with id and price as numbers. {"id": 1, "price": 9.99, "id": 2, "price": 19.99} is invalid JSON with duplicate keys. [{"id": 1, "price": "9.99"}, {"id": 2, "price": "19.99"}] uses price as strings, which is allowed but less ideal. {"products": {"id": 1, "price": 9.99}, {"id": 2, "price": 19.99}} has invalid JSON syntax.

3. Final Answer:

   [{"id": 1, "price": 9.99}, {"id": 2, "price": 19.99}] -> Option C

4. Quick Check:

   Array of objects with numeric price = [{"id": 1, "price": 9.99}, {"id": 2, "price": 19.99}] [OK]

Hint: Use JSON array with objects for multiple items [OK]

Common Mistakes:

• Using duplicate keys in one object
• Incorrect JSON syntax with braces and commas
• Using strings for numeric values unnecessarily