Deploy a Simple Web Application on PaaS
Using Google App Engine (Hello World App)
Introduction
Platform as a Service (PaaS) provides a cloud environment where developers can build, deploy, and manage applications without managing servers. In this experiment, we deploy a simple “Hello World” web application using Google App Engine.
What is Google App Engine?
Google App Engine (GAE) is a fully managed PaaS platform that allows developers to deploy web applications without worrying about infrastructure, scaling, or server management.
Step 1: Prerequisites
- Google Account
- Install Google Cloud SDK
- Python installed (for this example)
- Basic knowledge of command prompt
Step 2: Create a Simple Web Application
1️⃣ Create Project Folder
Create a new folder named:
hello-app
2️⃣ Create Python File (main.py)
Create a file named main.py and add the following code:
from flask import Flask
app = Flask(__name__)
@app.route("/")
def hello():
return "Hello, World!"
if __name__ == "__main__":
app.run(host="127.0.0.1", port=8080, debug=True)
3️⃣ Create requirements.txt
Create a file named requirements.txt:
Flask==2.2.2
4️⃣ Create app.yaml
Create a file named app.yaml:
runtime: python39
entrypoint: gunicorn -b :$PORT main:app
Step 3: Initialize Google Cloud
Open command prompt and run:
gcloud init
- Login with Google account
- Select or create a project
Step 4: Deploy the Application
Inside project folder, run:
gcloud app deploy
- Confirm region
- Wait for deployment
Step 5: View the Application
After deployment, run:
gcloud app browse
The browser will open and display:
Hello, World!
How PaaS Helped
- No server configuration required
- Automatic scaling
- Built-in security
- Easy deployment
- Managed infrastructure
Advantages of Using Google App Engine
- Fully managed service
- Auto scaling
- Pay-as-you-go pricing
- Easy integration with other Google Cloud services
Conclusion
Deploying a simple “Hello World” application on Google App Engine demonstrates how PaaS simplifies application deployment. Developers can focus on writing code while the platform handles infrastructure, scaling, and maintenance.
Viva Questions with Answers
1. What is PaaS?
Platform as a Service – a cloud model that provides a platform for developing and deploying applications.
2. Which PaaS platform was used in this example?
Google App Engine.
3. Do we need to manage servers in PaaS?
No.
4. What command is used to deploy the app?
gcloud app deploy
5. What does the sample application display?
Hello, World!