Assignment

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1️⃣ Flask: Introduction to Web Frameworks (5 Assignments)

Assignment 1: Install Flask and Create a Simple App

🔹 Task: Install Flask and run a basic "Hello, World!" app. 🔹 Example Snippet:

pip install flask

from flask import Flask

app = Flask(__name__)

@app.route("/")
def home():
    return "Hello, World!"

if __name__ == "__main__":
    app.run(debug=True)

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Assignment 2: Handle GET and POST Requests in Flask

🔹 Task: Create an endpoint that handles both GET and POST requests. 🔹 Example Snippet:

from flask import Flask, request

app = Flask(__name__)

@app.route("/greet", methods=["GET", "POST"])
def greet():
    if request.method == "POST":
        name = request.form.get("name", "User")
        return f"Hello, {name}!"
    return "Send a POST request with 'name' data."

if __name__ == "__main__":
    app.run(debug=True)

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Assignment 3: Use URL Parameters in Flask

🔹 Task: Extract a name from the URL and display it. 🔹 Example Snippet:

@app.route("/user/<name>")
def show_user(name):
    return f"Hello, {name}!"

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Assignment 4: Render HTML Templates in Flask

🔹 Task: Render an HTML template. 🔹 Example Snippet:

from flask import Flask, render_template

app = Flask(__name__)

@app.route("/")
def index():
    return render_template("index.html")

if __name__ == "__main__":
    app.run(debug=True)

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Assignment 5: Serve Static Files in Flask

🔹 Task: Serve a CSS file from a static folder. 🔹 Example Snippet:

<link rel="stylesheet" href="{{ url_for('static', filename='styles.css') }}">

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2️⃣ FastAPI: Building APIs (5 Assignments)

Assignment 6: Install FastAPI and Uvicorn

🔹 Task: Install FastAPI and run a basic API. 🔹 Example Command:

pip install fastapi uvicorn

🔹 Example Snippet:

from fastapi import FastAPI

app = FastAPI()

@app.get("/")
def read_root():
    return {"message": "Hello, FastAPI!"}

if __name__ == "__main__":
    import uvicorn
    uvicorn.run(app, host="127.0.0.1", port=8000)

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Assignment 7: Define Query Parameters in FastAPI

🔹 Task: Accept a query parameter in a GET request. 🔹 Example Snippet:

@app.get("/items/")
def read_item(q: str = "default"):
    return {"query": q}

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Assignment 8: Create a POST Endpoint in FastAPI

🔹 Task: Accept JSON data in a POST request. 🔹 Example Snippet:

from pydantic import BaseModel

class Item(BaseModel):
    name: str
    price: float

@app.post("/items/")
def create_item(item: Item):
    return {"message": f"Item {item.name} created!"}

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Assignment 9: Path Parameters in FastAPI

🔹 Task: Extract a parameter from the URL. 🔹 Example Snippet:

@app.get("/users/{user_id}")
def read_user(user_id: int):
    return {"user_id": user_id}

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Assignment 10: Handling Form Data in FastAPI

🔹 Task: Accept form data in a POST request. 🔹 Example Snippet:

from fastapi import Form

@app.post("/login/")
def login(username: str = Form(...), password: str = Form(...)):
    return {"username": username, "status": "logged in"}

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3️⃣ Middleware in FastAPI (5 Assignments)

Assignment 11: Create Custom Middleware for Logging

🔹 Task: Log each request. 🔹 Example Snippet:

from fastapi import Request
from fastapi.middleware import Middleware

@app.middleware("http")
async def log_requests(request: Request, call_next):
    print(f"Request: {request.method} {request.url}")
    response = await call_next(request)
    return response

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Assignment 12: Authentication Middleware

🔹 Task: Check for an API key in requests. 🔹 Example Snippet:

@app.middleware("http")
async def check_auth(request: Request, call_next):
    if "x-api-key" not in request.headers:
        return JSONResponse(status_code=403, content={"message": "Unauthorized"})
    return await call_next(request)

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Assignment 13: Modify Request Headers in Middleware

🔹 Task: Add a custom header to each response. 🔹 Example Snippet:

@app.middleware("http")
async def add_custom_header(request: Request, call_next):
    response = await call_next(request)
    response.headers["X-Custom-Header"] = "MyCustomValue"
    return response

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Assignment 14: Log Response Time in Middleware

🔹 Task: Log how long each request takes. 🔹 Example Snippet:

import time

@app.middleware("http")
async def log_response_time(request: Request, call_next):
    start_time = time.time()
    response = await call_next(request)
    process_time = time.time() - start_time
    print(f"Request took {process_time} seconds")
    return response

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Assignment 15: Validate Request Payload Using Middleware

🔹 Task: Reject invalid JSON requests. 🔹 Example Snippet:

@app.middleware("http")
async def validate_json_request(request: Request, call_next):
    if request.headers.get("Content-Type") != "application/json":
        return JSONResponse(status_code=400, content={"message": "Invalid Content-Type"})
    return await call_next(request)

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4️⃣ Connecting FastAPI with MongoDB & SQLAlchemy (5 Assignments)

Assignment 16: Install and Connect to MongoDB

🔹 Task: Install pymongo and connect FastAPI to MongoDB. 🔹 Example Command:

pip install pymongo

🔹 Example Snippet:

from pymongo import MongoClient

client = MongoClient("mongodb://localhost:27017/")
db = client["mydatabase"]

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Assignment 17: Insert a Document into MongoDB

🔹 Task: Insert data using FastAPI. 🔹 Example Snippet:

@app.post("/add_user/")
def add_user(name: str):
    db.users.insert_one({"name": name})
    return {"message": "User added"}

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Assignment 18: Retrieve Data from MongoDB

🔹 Task: Fetch all users from MongoDB. 🔹 Example Snippet:

@app.get("/users/")
def get_users():
    users = list(db.users.find({}, {"_id": 0}))
    return {"users": users}

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Assignment 19: Connect FastAPI with SQLAlchemy

🔹 Task: Install SQLAlchemy and create a SQLite database. 🔹 Example Command:

pip install sqlalchemy sqlite

🔹 Example Snippet:

from sqlalchemy import create_engine

engine = create_engine("sqlite:///test.db")

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Assignment 20: Perform CRUD Operations Using SQLAlchemy

🔹 Task: Insert and retrieve data using SQLAlchemy. 🔹 Example Snippet:

from sqlalchemy.orm import Session

session = Session(bind=engine)
session.add(User(name="Alice"))
session.commit()

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