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shravan jain
shravan jain

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Mastering Flask Blueprints: The First Step to Scalable Web Apps

As I started learning Flask, I was building simple apps just to understand the basics and get comfortable with it. Once I felt a bit more confident, I decided to start a project, a site monitoring tool. Since I knew the project would grow and include more functionality, I realized that things should be organized better. That’s when I came across Flask Blueprints. A Blueprint is a modular way to organize code and routes into separate components. Today, I set up my first Blueprint in Flask and here’s how it went.

Project structure

blueprint-example/
├── run.py
└── app/
    └── routes.py
    └── __init__.py
    └── templates/
        └── index.html
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Step 1: Creating a simple Blueprint

from flask import Blueprint,render_template
#creating a flask blueprint called 'main_route'
main_route=Blueprint('main_route',__name__)
#define a route on this blueprint
@main_route.route('/')
def blue_example():
    return render_template('index.html')

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Step 2: Register the blueprint

from flask import Flask

app=Flask(__name__)

def blue_example():
    from .routes import main_route
    app.register_blueprint(main_route)#registering my blueprint to my flask app instance
    return app

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Step 3: Run the app

from app import blue_example

app=blue_example()#Calling a function to get flask app instance

if __name__ == '__main__':
    app.run(debug=True) #run the app in debug mode
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What i found use full?

I basically had an idea of how this works because I had learned about MVC (Model, View, and Controller) in Java. The working process of both is quite similar, so I was able to grasp it a bit quicker.

Here are a few things I found helpful about using Blueprints:

  • It's a clean way to split the code logically. For example, separating routes and the dashboard into components makes the structure much easier to work with.

  • It's much easier to manage as the app grows and more features are added.

  • It makes the project more organized and scalable, which is especially useful when working in teams or revisiting the project later.

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