MongoDB integration with Motor in FastAPI - Mini Project: Build & Apply

MongoDB Integration with Motor in FastAPI

📖 Scenario: You are building a simple FastAPI application that stores and retrieves user information from a MongoDB database. You will use Motor, an asynchronous MongoDB driver, to connect and interact with the database.

🎯 Goal: Create a FastAPI app that connects to MongoDB using Motor, inserts a user document, and retrieves it asynchronously.

📋 What You'll Learn

Create a Motor client connected to MongoDB

Define a database and collection for users

Insert a user document asynchronously

Retrieve the inserted user document asynchronously

💡 Why This Matters

🌍 Real World

Many modern web applications use FastAPI with MongoDB for scalable, asynchronous data storage and retrieval.

💼 Career

Understanding how to integrate FastAPI with MongoDB using Motor is valuable for backend developers working on asynchronous Python web services.

1

Setup Motor Client and FastAPI App

Import FastAPI and AsyncIOMotorClient from motor.motor_asyncio. Create a FastAPI app called app. Create a Motor client called client connected to mongodb://localhost:27017. Define a database called testdb from the client.

FastAPI

from fastapi import FastAPI
from motor.motor_asyncio import AsyncIOMotorClient

# Create FastAPI app
# Your code here

Need a hint?

Use AsyncIOMotorClient to connect to MongoDB asynchronously. Create the FastAPI app instance first.

2

Define User Collection

Create a variable called user_collection that refers to the users collection inside the testdb database.

FastAPI

from fastapi import FastAPI
from motor.motor_asyncio import AsyncIOMotorClient

app = FastAPI()
client = AsyncIOMotorClient("mongodb://localhost:27017")
db = client.testdb

# Define the users collection
# Your code here

Need a hint?

Access the collection by using db.users.

3

Create Async Endpoint to Insert User

Define an async function called create_user with a POST route at /users/. Inside the function, insert a document with {"name": "Alice", "age": 30} into user_collection using insert_one asynchronously.

FastAPI

from fastapi import FastAPI
from motor.motor_asyncio import AsyncIOMotorClient

app = FastAPI()
client = AsyncIOMotorClient("mongodb://localhost:27017")
db = client.testdb
user_collection = db.users

# Create async POST endpoint to insert user
# Your code here

Need a hint?

Use @app.post("/users/") decorator and define an async function. Use await with insert_one.

4

Create Async Endpoint to Retrieve User

Define an async function called get_user with a GET route at /users/{name}. Inside the function, find one document in user_collection where name matches the path parameter. Return the found document as a dictionary, converting _id to string.

FastAPI

from fastapi import FastAPI
from motor.motor_asyncio import AsyncIOMotorClient

app = FastAPI()
client = AsyncIOMotorClient("mongodb://localhost:27017")
db = client.testdb
user_collection = db.users

@app.post("/users/")
async def create_user():
    user = {"name": "Alice", "age": 30}
    result = await user_collection.insert_one(user)
    return {"inserted_id": str(result.inserted_id)}

# Create async GET endpoint to retrieve user by name
# Your code here

Need a hint?

Use @app.get("/users/{name}") and an async function with a name parameter. Use await with find_one. Convert _id to string before returning.