Gain insights into using Python to consume and create REST APIs, delving into HTTP methods like GET and PUT. Ideal for enhancing intermediate Python skills.

Flask.tar.gz

Get Products

Get Product

Create Product

Update Product

Delete Product

Product OPTIONS

REST is the most used mechanism to publish APIs for general consumption. Each language has its own set of libraries and methods that help a developer consume these APIs. This course will teach you how to use Python and its libraries for consuming and creating REST APIs in the easiest way possible.

In the first part of this course, you’ll learn how to work with Python in using REST APIs for various scenarios. Then, in the second part, you’ll focus on building your own REST APIs using the HTTP methods, including GET, PUT, etc.

This course is geared toward intermediate users who have a basic understanding of Python and want to improve their skills in using existing REST APIs and building their REST API implementations.

Python REST API Development: A Comprehensive Guide

In REST, when a client needs to query a service about the operations it supports, the client issues an OPTIONS request. The OPTIONS request is always issued against the root of the service. Hence, from a URI perspective, OPTIONS and POST use the same template. We'll see how to implement the OPTIONS endpoint to inform the clients about the operations that the products API supports.

In Flask, to provide a custom OPTIONS response, we need to return the response from a method decorated with the `@after_request` decorator. Let's see how to use `@after_request` to provide our own response to an OPTIONS request.

# Steps

1. Open `server/api/products_api.py`.

2. Add a new method that accepts the `response` object as the parameter. Name the method `after_request`.
```python
def after_request(response):
```

3. Add the following code to the `after_request` method.
```python
if request.method == 'OPTIONS':
     response = make_response()
     response.headers.add('Access-Control-Allow-Methods',
                       	  'GET, POST, PUT, DELETE, OPTIONS')

return response
```

4. Decorate the method with the route decorator `products_blueprint.after_request`.
```python
@products_blueprint.after_request
```

5. Run the application.

6. Using your preferred tool, hit the following URL. When testing on the Educative platform, please replace `http://localhost` with the URL provided in the SPA widget.
```
$ curl -X OPTIONS http://localhost:5000/api/products
```

7. The following output should be obtained.
```
< HTTP/1.1 200 OK
< Access-Control-Allow-Methods: GET, POST, PUT, DELETE, OPTIONS
< Content-Length: 0
```

Learn how to implement our API using Flask to inform clients about supported operations.

Introduction

Client

Server

Project: Tickets API

Conclusion

Implementing OPTIONS to Inform Clients About Supported Operation