Webhook payload design in Rest API - Mini Project: Build & Apply

Webhook Payload Design

📖 Scenario: You are building a simple webhook system for an online store. When a new order is placed, the system sends a notification with order details to a partner service. You need to design the webhook payload that contains the order information.

🎯 Goal: Create a webhook payload as a JSON object that includes order details such as order ID, customer name, list of items with quantity and price, and total amount.

📋 What You'll Learn

Create a dictionary called order with exact keys and values for order details

Add a variable called currency with the value "USD"

Use a dictionary comprehension to create a new dictionary items_summary with item names as keys and total price (quantity * price) as values

Print the final webhook payload as a JSON string

💡 Why This Matters

🌍 Real World

Webhook payloads are used to send real-time notifications between web services, such as notifying a shipping partner when a new order is placed.

💼 Career

Understanding how to design and format webhook payloads is important for backend developers and API engineers working with integrations and event-driven systems.

1

Create the order data structure

Create a dictionary called order with these exact entries: "order_id": 12345, "customer": "John Doe", and "items" which is a list of dictionaries with these exact items: {"name": "T-shirt", "quantity": 2, "price": 15.0} and {"name": "Jeans", "quantity": 1, "price": 40.0}.

Rest API

# Create the order dictionary with order_id, customer, and items list
# Your code here

Hint

Use a dictionary with keys order_id, customer, and items. The items key holds a list of dictionaries for each product.

2

Add currency configuration

Create a variable called currency and set it to the string "USD".

Rest API

order = {
    "order_id": 12345,
    "customer": "John Doe",
    "items": [
        {"name": "T-shirt", "quantity": 2, "price": 15.0},
        {"name": "Jeans", "quantity": 1, "price": 40.0}
    ]
}
# Create a variable called currency and set it to "USD"
# Your code here

Hint

Just create a simple variable named currency and assign the string "USD" to it.

3

Create items summary with dictionary comprehension

Use a dictionary comprehension to create a new dictionary called items_summary where each key is the item name from order["items"] and the value is the total price calculated as quantity * price.

Rest API

order = {
    "order_id": 12345,
    "customer": "John Doe",
    "items": [
        {"name": "T-shirt", "quantity": 2, "price": 15.0},
        {"name": "Jeans", "quantity": 1, "price": 40.0}
    ]
}
currency = "USD"
# Create items_summary dictionary with item names as keys and quantity * price as values
# Your code here

Hint

Use a dictionary comprehension with for item in order["items"]. The key is item["name"] and the value is item["quantity"] * item["price"].

4

Print the final webhook payload

Print the final webhook payload as a JSON string. Create a dictionary called webhook_payload with keys: order_id, customer, currency, and items_summary. Then print it using print() and json.dumps() with indentation of 2 spaces.

Rest API

order = {
    "order_id": 12345,
    "customer": "John Doe",
    "items": [
        {"name": "T-shirt", "quantity": 2, "price": 15.0},
        {"name": "Jeans", "quantity": 1, "price": 40.0}
    ]
}
currency = "USD"
items_summary = {item["name"]: item["quantity"] * item["price"] for item in order["items"]}

# Import json module
import json

# Create webhook_payload dictionary and print it as JSON string with indent=2
# Your code here

Hint

Import the json module. Create webhook_payload dictionary with the required keys and values. Use print(json.dumps(webhook_payload, indent=2)) to display the JSON string nicely.

Practice

1. What is the main purpose of a webhook payload in a REST API?

easy

A. To store user login credentials securely

B. To create a user interface for the API

C. To send event details from one app to another automatically

D. To encrypt data between client and server

Solution

1. Step 1: Understand webhook payload role

   A webhook payload is a message sent automatically when an event happens, sharing event details.

2. Step 2: Compare options with webhook purpose

   Only To send event details from one app to another automatically describes sending event details automatically, which matches webhook payload use.

3. Final Answer:

   To send event details from one app to another automatically -> Option C

4. Quick Check:

   Webhook payload = event details sent automatically [OK]

Hint: Webhook payloads always send event info automatically [OK]

Common Mistakes:

• Confusing payload with user authentication
• Thinking payload creates UI
• Assuming payload encrypts data

2. Which of the following is the correct JSON structure for a webhook payload that includes event name and timestamp?

easy

A. [ "event": "user_signup", "timestamp": "2024-06-01T12:00:00Z" ]

B. { "event": "user_signup", "timestamp": "2024-06-01T12:00:00Z" }

C. { event = "user_signup", timestamp = "2024-06-01T12:00:00Z" }

D. "event": "user_signup", "timestamp": "2024-06-01T12:00:00Z"

Solution

1. Step 1: Identify valid JSON syntax

   JSON objects use curly braces {}, keys and values separated by colon :, keys in double quotes, and comma between pairs.

2. Step 2: Check each option's syntax

   { "event": "user_signup", "timestamp": "2024-06-01T12:00:00Z" } uses correct JSON object syntax. [ "event": "user_signup", "timestamp": "2024-06-01T12:00:00Z" ] uses square brackets which denote arrays, not key-value pairs. { event = "user_signup", timestamp = "2024-06-01T12:00:00Z" } uses equals sign instead of colon. "event": "user_signup", "timestamp": "2024-06-01T12:00:00Z" is missing braces.

3. Final Answer:

   { "event": "user_signup", "timestamp": "2024-06-01T12:00:00Z" } -> Option B

4. Quick Check:

   Valid JSON object = { "event": "user_signup", "timestamp": "2024-06-01T12:00:00Z" } [OK]

Hint: JSON objects use braces and colons, not brackets or equals [OK]

Common Mistakes:

• Using square brackets instead of braces for objects
• Using equals sign instead of colon
• Omitting braces around JSON

3. Given this webhook payload JSON:

{"event": "order_created", "timestamp": "2024-06-01T15:30:00Z", "data": {"order_id": 123, "amount": 49.99}}

What value will the receiving app find for data.amount?

medium

A. 49.99

B. order_created

C. "amount"

D. 123

Solution

1. Step 1: Locate the data.amount field in JSON

   Inside the "data" object, the key "amount" has the value 49.99 (a number).

2. Step 2: Match the value to options

   49.99 matches the numeric value 49.99. Other options are either keys or unrelated values.

3. Final Answer:

   49.99 -> Option A

4. Quick Check:

   data.amount = 49.99 [OK]

Hint: Look inside nested 'data' object for 'amount' key [OK]

Common Mistakes:

• Confusing order_id with amount
• Selecting string key instead of value
• Choosing event name instead of data field

4. You receive this webhook payload:

{"event": "payment_failed", "timestamp": "2024-06-01T16:00:00Z", "data": {"payment_id": 789}}

What is wrong with this payload?

medium

A. Payment ID should be a string, not a number

B. Timestamp format is incorrect

C. Event name should be inside data object

D. Missing closing brace for the JSON object

Solution

1. Step 1: Check JSON completeness

   The payload ends without a closing brace '}' for the outermost JSON object, making it invalid JSON.

2. Step 2: Verify other parts

   Timestamp format is ISO 8601 and correct. Event name is correctly outside data. Payment ID can be number or string depending on design.

3. Final Answer:

   Missing closing brace for the JSON object -> Option D

4. Quick Check:

   JSON must have matching braces [OK]

Hint: Always check for matching braces in JSON payloads [OK]

Common Mistakes:

• Ignoring missing braces
• Assuming timestamp format is wrong
• Thinking event must be inside data

5. You want to design a webhook payload for a "user_deleted" event that includes the user ID and deletion reason. Which JSON payload design is best for clarity and easy parsing?

hard

A. { "event": "user_deleted", "timestamp": "2024-06-01T17:00:00Z", "data": { "user_id": 456, "reason": "requested by user" } }

B. { "user_deleted": true, "user": 456, "reason": "requested by user" }

C. { "event": "user_deleted", "user_id": 456, "reason": "requested by user" }

D. { "event": "user_deleted", "timestamp": "2024-06-01T17:00:00Z", "user": { "id": 456, "reason": "requested by user" } }

Solution

1. Step 1: Check for standard webhook fields

   { "event": "user_deleted", "timestamp": "2024-06-01T17:00:00Z", "data": { "user_id": 456, "reason": "requested by user" } } includes event name, timestamp, and a nested data object holding user_id and reason, which is clear and standard.

2. Step 2: Compare other options for clarity and parsing

   { "user_deleted": true, "user": 456, "reason": "requested by user" } lacks event and timestamp keys properly named. { "event": "user_deleted", "user_id": 456, "reason": "requested by user" } mixes data fields at root level, less organized. { "event": "user_deleted", "timestamp": "2024-06-01T17:00:00Z", "user": { "id": 456, "reason": "requested by user" } } nests reason inside user object, which is less intuitive.

3. Final Answer:

   { "event": "user_deleted", "timestamp": "2024-06-01T17:00:00Z", "data": { "user_id": 456, "reason": "requested by user" } } -> Option A

4. Quick Check:

   Standard event + timestamp + data object = { "event": "user_deleted", "timestamp": "2024-06-01T17:00:00Z", "data": { "user_id": 456, "reason": "requested by user" } } [OK]

Hint: Use event, timestamp, and data object for clear payloads [OK]

Common Mistakes:

• Omitting timestamp
• Mixing data fields at root level
• Nesting unrelated fields inside user