app.py

from flask import Flask, render_template, request, redirect, url_for
from sqlalchemy import create_engine, Column, Integer, String, DateTime
from sqlalchemy.orm import sessionmaker
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy import create_engine
import pyodbc
import os
from azure.identity import DefaultAzureCredential
from azure.keyvault.secrets import SecretClient
from azure.core.exceptions import ResourceNotFoundError

# Initialise Flask App
app = Flask(__name__)

# Create managed identity credentials
credential = DefaultAzureCredential()

# Create a SecretClient using managed identity credentials
key_vault_url = "https://hamim-key-vault.vault.azure.net/"
secret_client = SecretClient(vault_url=key_vault_url, credential=credential)

# Retrieve database connection details from Azure Key Vault

server = secret_client.get_secret("server-name").value

try:
    server = secret_client.get_secret("server-name").value
    database = secret_client.get_secret("database-name").value
    username = secret_client.get_secret("server-username").value
    password = secret_client.get_secret("server-password").value
    print('Secrete retrieved')
except ResourceNotFoundError:
    raise Exception("Database connection details not found in Azure Key Vault")

driver= '{ODBC Driver 18 for SQL Server}'

# Create the connection string
connection_string=f'Driver={driver};\
    Server=tcp:{server},1433;\
    Database={database};\
    Uid={username};\
    Pwd={password};\
    Encrypt=yes;\
    TrustServerCertificate=no;\
    Connection Timeout=30;'

# Create the engine to connect to the database
engine = create_engine("mssql+pyodbc:///?odbc_connect={}".format(connection_string))
engine.connect()

# Create the Session
Session = sessionmaker(bind=engine)

# Define the Order data model
Base = declarative_base()

class Order(Base):
    __tablename__ = 'orders'
    date_uuid = Column('date_uuid', String, primary_key=True)
    user_id = Column('User ID', String, primary_key=True)
    card_number = Column('Card Number', String)
    store_code = Column('Store Code', String)
    product_code = Column('product_code', String)
    product_quantity = Column('Product Quantity', Integer)
    order_date = Column('Order Date', DateTime)
    shipping_date = Column('Shipping Date', DateTime)

# define routes
# route to display orders
@app.route('/')
def display_orders():

    page = int(request.args.get('page', 1))
    rows_per_page = 25

    # Calculate the start and end indices for the current page
    start_index = (page - 1) * rows_per_page
    end_index = start_index + rows_per_page

    # Create a session to interact with the database
    session = Session()

    # Fetch a subset of data for the current page
    current_page_orders = session.query(Order).order_by(Order.user_id, Order.date_uuid).slice(start_index, end_index).all()

    # Calculate the total number of pages
    total_rows = session.query(Order).count()
    total_pages = (total_rows + rows_per_page - 1) // rows_per_page

    # Close the session
    session.close()

    return render_template('orders.html', orders=current_page_orders, page=page, total_pages=total_pages)

# route to add orders
@app.route('/add_order', methods=['POST'])
def add_order():
    date_uuid = request.form.get('date_uuid')
    user_id = request.form.get('user_id')
    card_number = request.form.get('card_number')
    store_code = request.form.get('store_code')
    product_code = request.form.get('product_code')
    product_quantity = request.form.get('product_quantity')
    order_date = request.form.get('order_date')
    shipping_date = request.form.get('shipping_date')
    
    # Create a session to interact with the database
    session = Session()

    # Create a new order object using the form data
    new_order = Order(
        date_uuid=date_uuid,
        user_id=user_id,
        card_number=card_number,
        store_code=store_code,
        product_code=product_code,
        product_quantity=product_quantity,
        order_date=order_date,
        shipping_date=shipping_date
    )

    # Add the new order to the session and commit to the database
    session.add(new_order)
    session.commit()

    return redirect(url_for('display_orders'))

# run the app
if __name__ == '__main__':
    app.run(host='0.0.0.0', port=5000, debug=True)