Flask Blueprint Example

# my_blueprint.py
from flask import Blueprint, render_template

class MyBlueprint(object):
  def __init__(self, app, *args, **kwargs):
    if app is not None:
      self.init_app(app, **kwargs)

  def init_app(self, app, **kwargs):
    url_prefix = kwargs['url_prefix'] if 'url_prefix' in kwargs else '/DEFAULT_URL_PREFIX'
    my_bp = Blueprint('my_bp', __name__, template_folder='mybp_templates')
    my_bp.add_url_rule('/', 'home', self.my_home_route)
    app.register_blueprint(my_bp, url_prefix=url_prefix)

  def my_home_route(self):
    return render_template('home.html')

# mybp_templates/home.html
<h1>My Blueprint Home!</h1>

# app.py
from flask import Flask
from my_blueprint import MyBlueprint

app = Flask(__name__)
MyBlueprint(app, url_prefix='/my-blueprint')
app.run()

# run `python app.py`
# visit url: http://127.0.0.1:5000/my-blueprint