Lambda function with DynamoDB - Mini Project: Build & Apply

Lambda function with DynamoDB

📖 Scenario: You are building a simple AWS Lambda function that interacts with a DynamoDB table to store and retrieve user information. This is a common task when creating serverless applications that need to save data in the cloud.

🎯 Goal: Create a Lambda function that inserts a user record into a DynamoDB table and then retrieves it by user ID.

📋 What You'll Learn

Create a DynamoDB table data structure with exact user data

Add a configuration variable for the table name

Write the core logic to insert a user record into the DynamoDB table

Write the final code to retrieve the user record by user ID

💡 Why This Matters

🌍 Real World

Serverless applications often use AWS Lambda functions to interact with DynamoDB tables for storing and retrieving data without managing servers.

💼 Career

Understanding how to write Lambda functions that work with DynamoDB is essential for cloud developers and backend engineers working with AWS services.

1

DATA SETUP: Create a DynamoDB table data structure

Create a dictionary called dynamodb_table that represents a DynamoDB table with one user record. The user record must have these exact key-value pairs: 'UserID': 'user123', 'Name': 'Alice', and 'Age': 30.

DynamoDB

# Create the dynamodb_table dictionary with one user record
# Your code here

Need a hint?

Use a dictionary where the key is the user ID and the value is another dictionary with the user details.

2

CONFIGURATION: Add a table name variable

Create a variable called table_name and set it to the string 'Users' to represent the DynamoDB table name.

DynamoDB

dynamodb_table = {
    'user123': {
        'UserID': 'user123',
        'Name': 'Alice',
        'Age': 30
    }
}
# Create the table_name variable and set it to 'Users'
# Your code here

Need a hint?

This variable holds the name of the DynamoDB table you will use in your Lambda function.

3

CORE LOGIC: Insert a new user record

Write a function called insert_user that takes three parameters: user_id, name, and age. Inside the function, add a new entry to the dynamodb_table dictionary with the key as user_id and the value as a dictionary containing 'UserID', 'Name', and 'Age' with the given values.

DynamoDB

dynamodb_table = {
    'user123': {
        'UserID': 'user123',
        'Name': 'Alice',
        'Age': 30
    }
}
table_name = 'Users'
# Define the insert_user function to add a new user record
# Your code here

Need a hint?

Use the function parameters to create a new dictionary and assign it to the dynamodb_table with the key user_id.

4

COMPLETION: Retrieve a user record by user ID

Write a function called get_user that takes one parameter user_id and returns the user record from dynamodb_table for that user_id. Use the get method of the dictionary to safely retrieve the record.

DynamoDB

dynamodb_table = {
    'user123': {
        'UserID': 'user123',
        'Name': 'Alice',
        'Age': 30
    }
}
table_name = 'Users'

def insert_user(user_id, name, age):
    dynamodb_table[user_id] = {
        'UserID': user_id,
        'Name': name,
        'Age': age
    }

# Define the get_user function to retrieve a user record by user_id
# Your code here

Need a hint?

Use the dictionary get method to return the user record or null if not found.