How to Create a Simple Web API with Flask

Creating a simple Web API with Flask is straightforward. Flask is a lightweight web framework for Python, making it ideal for building APIs quickly. Below are the steps to create a simple Web API with Flask:

Step 1: Install Flask

If you haven't already installed Flask, you can do so using pip:

1pip install Flask
2

Step 2: Create your Flask app

Create a Python script (e.g., flaskapi.py) and import Flask:

1from flask import Flask
2
3app = Flask(__name__)
4

Step 3: Define your API endpoints

You can define routes for different API endpoints using Flask's @app.route decorator. Below is an example of defining a simple endpoint that returns a JSON response:

1@app.route('/api/hello')
2def hello():
3    return {'message': 'Hello, World!'}
4

Step 4: Run the Flask app

At the end of your script, add the following code to run the Flask app:

1if __name__ == '__main__':
2    app.run(debug=True)
3

Step 5: Test your API

Save the changes to flaskapi.py and run it:

1flask --app flaskapi run
2

Your Flask app should now be running locally. You can test your API by sending requests to http://127.0.0.1:5000/api/hello using tools like curl, Postman, or your web browser. You should see a JSON response {"message": "Hello, World!"}.

That's it! You've created a simple Web API with Flask. From here, you can expand your API by adding more endpoints, handling request parameters, integrating with databases, implementing authentication, etc., based on your requirements.