models.py

from app import app, db


DrinkIngredients = db.Table('DrinkIngredients',
    db.Column('drink_id', db.Integer, db.ForeignKey('drink.id')),
    db.Column('ingredient_id', db.Integer, db.ForeignKey('ingredient.id'))
)


class Drink(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(64), index=True, unique=True)
    Ingredients = db.relationship('Ingredient',
                                  secondary=DrinkIngredients,
                                  backref=db.backref('drink', lazy='dynamic'),
                                  lazy='dynamic')

    def __init__(self, name):
        self.name = name

    def __repr__(self):
        return '<Drink %r>' % (self.name)


class Ingredient(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(140))

    def __init__(self, name):
        self.name = name

    def __repr__(self):
        return '<Ingredient %r>' % (self.name)