Book Image

Hands-On RESTful Python Web Services - Second Edition

By : Gaston C. Hillar
1 (1)
Book Image

Hands-On RESTful Python Web Services - Second Edition

1 (1)
By: Gaston C. Hillar

Overview of this book

Python is the language of choice for millions of developers worldwide that builds great web services in RESTful architecture. This second edition of Hands-On RESTful Python Web Services will cover the best tools you can use to build engaging web services. This book shows you how to develop RESTful APIs using the most popular Python frameworks and all the necessary stacks with Python, combined with related libraries and tools. You’ll learn to incorporate all new features of Python 3.7, Flask 1.0.2, Django 2.1, Tornado 5.1, and also a new framework, Pyramid. As you advance through the chapters, you will get to grips with each of these frameworks to build various web services, and be shown use cases and best practices covering when to use a particular framework. You’ll then successfully develop RESTful APIs with all frameworks and understand how each framework processes HTTP requests and routes URLs. You’ll also discover best practices for validation, serialization, and deserialization. In the concluding chapters, you will take advantage of specific features available in certain frameworks such as integrated ORMs, built-in authorization and authentication, and work with asynchronous code. At the end of each framework, you will write tests for RESTful APIs and improve code coverage. By the end of the book, you will have gained a deep understanding of the stacks needed to build RESTful web services.
Table of Contents (19 chapters)
Title Page
Dedication
About Packt
Contributors
Preface
Index

Creating schemas to validate, serialize, and deserialize users


Now we will create the Flask-Marshmallow schema that we will use to validate, serialize, and deserialize the previously declared User model. Open the models.py file within the service folder and add the following code after the existing lines. The code file for the sample is included in the restful_python_2_03_02 folder, in the Flask01/service/models.py file:

class UserSchema(ma.Schema): 
    id = fields.Integer(dump_only=True) 
    name = fields.String(required=True,  
        validate=validate.Length(3)) 
    url = ma.URLFor('service.userresource',  
        id='<id>',  
        _external=True) 

The code declares the UserSchema schema, specifically a subclass of the ma.Schema class. Remember that the previous code we wrote for the service/models.py file created a flask_marshmallow.Mashmallow instance named ma.

We declare the attributes that represent fields as instances of the appropriate class declared in the marshmallow...