Building a Data-Driven Web Application with Python
Building a data-driven web application with Python involves creating a web app that interacts with data stored in a database, displays it to users, and often lets users manipulate that data (add, update, delete, etc.).
Here’s a step-by-step guide using Flask, one of Python’s most popular web frameworks.
✅ What You’ll Need
🛠️ Tools & Technologies
Python
Flask (Web framework)
SQLite or PostgreSQL/MySQL (Database)
SQLAlchemy (ORM - Object Relational Mapper)
HTML/CSS for frontend
🚀 Step-by-Step Guide
🔹 Step 1: Install Dependencies
bash
Copy
Edit
pip install flask flask_sqlalchemy
🔹 Step 2: Project Structure
pgsql
Copy
Edit
data_app/
├── app.py
├── templates/
│ └── index.html
└── models.py
🔹 Step 3: Create the Flask App (app.py)
python
Copy
Edit
from flask import Flask, render_template, request, redirect
from models import db, User
app = Flask(__name__)
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///users.db'
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False
db.init_app(app)
@app.before_first_request
def create_tables():
db.create_all()
@app.route('/')
def index():
users = User.query.all()
return render_template('index.html', users=users)
@app.route('/add', methods=['POST'])
def add_user():
name = request.form.get('name')
email = request.form.get('email')
if name and email:
new_user = User(name=name, email=email)
db.session.add(new_user)
db.session.commit()
return redirect('/')
if __name__ == '__main__':
app.run(debug=True)
🔹 Step 4: Define the Data Model (models.py)
python
Copy
Edit
from flask_sqlalchemy import SQLAlchemy
db = SQLAlchemy()
class User(db.Model):
id = db.Column(db.Integer, primary_key=True)
name = db.Column(db.String(80), nullable=False)
email = db.Column(db.String(120), unique=True, nullable=False)
def __repr__(self):
return f'<User {self.name}>'
🔹 Step 5: Create HTML Template (templates/index.html)
html
Copy
Edit
<!DOCTYPE html>
<html>
<head>
<title>Data-Driven Web App</title>
</head>
<body>
<h1>Users</h1>
<ul>
{% for user in users %}
<li>{{ user.name }} - {{ user.email }}</li>
{% endfor %}
</ul>
<h2>Add User</h2>
<form method="POST" action="/add">
<input name="name" placeholder="Name" required>
<input name="email" placeholder="Email" required>
<button type="submit">Add</button>
</form>
</body>
</html>
📊 What Makes It “Data-Driven”?
The UI reflects the database: all users are read from the database.
User input updates the database: form submission adds new users.
You can easily extend it to include edit, delete, search, filter, etc.
🧩 Optional Enhancements
Add Bootstrap for styling.
Use WTForms for better form handling.
Switch to PostgreSQL for production environments.
Add authentication (Flask-Login).
Use AJAX for dynamic updates without page reloads.
✅ Summary
Component Description
Flask Handles routing and web server
SQLAlchemy Connects Python to the database
SQLite Stores the user data
HTML Displays the data in the browser
Learn Full Stack Python Course in Hyderabad
Read More
How to Use SQLAlchemy with Flask for Database Management
Introduction to MongoDB for Full Stack Python
Creating and Managing Relationships in Databases with Django ORM
Implementing Authentication with Databases in Python
Visit Our IHUB Talent Training Institute in Hyderabad
Comments
Post a Comment