Scaling for Demand: Deploying Python Applications Using MongoDB Atlas on Azure App Service

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python3 -m venv venv

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source venv/bin/activate

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Flask==2.2.2
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pymongo==4.3.3
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python-dotenv==0.21.1
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black==22.12.0

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pip install -r requirements.txt

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import bson 
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import os
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from dotenv import load_dotenv 
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from flask import Flask, render_template, request
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from pymongo import MongoClient
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from pymongo.collection import Collection
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from pymongo.database import Database

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app: Flask = Flask(__name__)
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# our initial form page 
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@app.route(‘/’) 
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def index():
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	return “Hi!”

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flask run

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flask run -p [port number]

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import bson 
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import os
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from dotenv import load_dotenv 
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from flask import Flask, render_template, request
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from pymongo import MongoClient
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from pymongo.collection import Collection
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from pymongo.database import Database
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# access your MongoDB Atlas cluster
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load_dotenv()
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connection_string: str = os.environ.get(“CONNECTION_STRING”)
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mongo_client: MongoClient = MongoClient(connection_string)
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# add in your database and collection from Atlas 
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database: Database = mongo_client.get_database(“bookshelf”)
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collection: Collection = database.get_collection(“books”)
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# instantiating new object with “name”
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app: Flask = Flask(__name__)
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# our initial form page
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@app.route(‘/’)
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def index():
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	return “Hi!”

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book = {“title”: “The Great Gatsby”, “author”: “F. Scott Fitzgerald”, “year”: 1925}
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collection.insert_one(book)

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# our initial form page
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@app.route(‘/’)
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def index():
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	return render_template(“index.html”)

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# CREATE and READ 
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@app.route('/books', methods=["GET", "POST"])
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def books():
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    if request.method == 'POST':
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        # CREATE
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        book: str = request.json['book']
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        pages: str = request.json['pages']
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        # insert new book into books collection in MongoDB
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        collection.insert_one({"book": book, "pages": pages})
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        return f"CREATE: Your book {book} ({pages} pages) has been added to your bookshelf.\n "
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    elif request.method == 'GET':
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        # READ
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        bookshelf = list(collection.find())
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        novels = []
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        for titles in bookshelf:
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            book = titles['book']
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            pages = titles['pages']
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            shelf = {'book': book, 'pages': pages}
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            novels.insert(0,shelf)
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        return novels

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{
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 	“book”: “The Odyssey”,
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 	“pages”: 384
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}

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# UPDATE
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@app.route("/books/<string:book_id>", methods = ['PUT'])
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def update_book(book_id: str):
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    new_book: str = request.json['book']
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    new_pages: str = request.json['pages']
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    collection.update_one({"_id": bson.ObjectId(book_id)}, {"$set": {"book": new_book, "pages": new_pages}})
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    return f"UPDATE: Your book has been updated to: {new_book} ({new_pages} pages).\n"

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# DELETE
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@app.route("/books/<string:book_id>", methods = ['DELETE'])
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def remove_book(book_id: str):
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    collection.delete_one({"_id": bson.ObjectId(book_id)})
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    return f"DELETE: Your book (id = {book_id}) has been removed from your bookshelf.\n"