If you have little experience in coding or Python and want to learn how to build full-fledged web apps, this Learning Path is for you. No prior experience with RESTful web services, Python, or Django is required, but basic Python programming experience is needed to understand the concepts covered.

Chapter 1, A Gentle Introduction to Python, introduces you to fundamental programming concepts. It guides you through getting Python up and running on your computer and introduces you to some of its constructs.

Chapter 2, Built-in Data Types, introduces you to Python built-in data types. Python has a very rich set of native data types, and this chapter will give you a description and a short example for each of them.

Chapter 3, Iterating and Making Decisions, teaches you how to control the flow of your code by inspecting conditions, applying logic, and performing loops.

Chapter 4, Functions, the Building Blocks of Code, teaches you how to write functions. Functions are the keys to reusing code, to reducing debugging time, and, in general, to writing better code.

Chapter 5, Saving Time and Memory, introduces you to the functional aspects of Python programming. This chapter teaches you how to write comprehensions and generators, which are powerful tools that you can use to speed up your code and save memory.

Chapter 6, OOP, Decorators, and Iterators, teaches you the basics of object-oriented programming with Python. It shows you the key concepts and all the potentials of this paradigm. It also shows you one of the most beloved characteristics of Python: decorators. Finally, it also covers the concept of iterators.

Chapter 7, Files and Data Persistence, teaches you how to deal with files, streams, data interchange formats, and databases, among other things.

Chapter 8, Testing, Profiling, and Dealing with Exceptions, teaches you how to make your code more robust, fast, and stable using techniques such as testing and profiling. It also formally defines the concept of exceptions.

Chapter 9, Concurrent Execution, is a challenging chapter that describes how to do many things at the same time. It provides an introduction to the theoretical aspects of this subject and then presents three nice exercises that are developed with different techniques, thereby enabling the reader to understand the differences between the paradigms presented.

Chapter 10, Debugging and Troubleshooting, shows you the main methods for debugging your code and some examples on how to apply them.

Chapter 11, Installing the Required Software and Tools, shows how to get started in our journey toward creating RESTful Web Services with Python and its most popular web framework—Django. We will install and configure the environments, the software, and the tools required to create RESTful Web Services with Django and Django REST framework. We will learn the necessary steps in Linux, macOS, and Windows. We will create our first app with Django, we will take a first look at the Django folders, files, and configurations, and we will make the necessary changes to activate Django REST framework. In addition, we will introduce and install command-line and GUI tools that we will use to interact with the RESTful Web Services that we will design, code, and test in the forthcoming chapters.

Chapter 12, Working with Models, Migrations, Serialization, and Deserialization, describes how to design a RESTful Web Service to interact with a simple SQLite database and perform CRUD operations with toys. We will define the requirements for our web service, and we will understand the tasks performed by each HTTP method and the different scopes. We will create a model to represent and persist toys and execute migrations in Django to create the required tables in the database. We will analyze the tables and learn how to manage the serialization of toy instances into JSON representations with Django REST framework and the reverse process.

Chapter 13, Creating API Views, is about executing the first version of a simple Django RESTful Web Service that interacts with a SQLite database. We will write API views to process diverse HTTP requests on a collection of toys and on a specific toy. We will work with the following HTTP verbs: GET, POST, and PUT. We will configure the URL patterns list to route URLs to views. We will start the Django development server and use command-line tools (curl and HTTPie) to compose and send diverse HTTP requests to our RESTful Web Service. We will learn how HTTP requests are processed in Django and our code. In addition, we will work with Postman, a GUI tool, to compose and send other HTTP requests to our RESTful Web Service.

Chapter 14, Using Generalized Behavior from the APIView Class, presents different ways to improve our simple Django RESTful Web Service. We will take advantage of many features included in the Django REST framework to remove duplicate code and add many features for the web service. We will use model serializers, understand the different accepted and returned content types, and the importance of providing accurate responses to the HTTP OPTIONS requests. We will make the necessary changes to the existing code to enable diverse parsers and renderers. We will learn how things work under the hoods in Django REST framework. We will work with different content types and note how the RESTful Web Service improves compared to its previous versions.

Chapter 15, Understanding and Customizing the Browsable API Feature, explains how to use one of the additional features that Django REST framework adds to our RESTful Web Service—the browsable API. We will use a web browser to work with our first web service built with Django. We will learn to make HTTP GET, POST, PUT, OPTIONS, and DELETE requests with the browsable API. We will be able to easily test CRUD operations with a web browser. The browsable API will allow us to easily interact with our RESTful Web Service.

Chapter 16, Using Constraints, Filtering, Searching, Ordering, and Pagination, describes the usage of the browsable API feature to navigate through the API with resources and relationships. We will add unique constraints to improve the consistency of the models in our RESTful Web Service. We will understand the importance of paginating results and configure and test a global limit/offset pagination scheme with Django REST framework. Then, we will create our own customized pagination class to ensure that requests won't be able to require a huge number of elements on a single page. We will configure filter backend classes and incorporate code into the models to add filtering, searching, and ordering capabilities to the class-based views. We will create a customized filter and make requests to filter, search, and order results. Finally, we will use the browsable API to test pagination, filtering, and ordering.

Chapter 17, Securing the API with Authentication and Permissions, presents the differences between authentication and permissions in Django, Django REST framework, and RESTful Web Services. We will analyze the authentication classes included in Django REST framework out of the box. We will follow the steps needed to provide security- and permissions-related data to models.

We will work with object-level permissions via customized permission classes and save information about users who make requests. We will configure permission policies and compose and send authenticated requests to understand how the permission policies work. We will use command-line tools and GUI tools to compose and send authenticated requests. We will browse the secure RESTful Web Service with the browsable API feature and work with a simple token-based authentication provided by Django REST framework to understand another way of authenticating requests.

Chapter 18, Applying Throttling Rules and Versioning Management, focuses on the importance of throttling rules and how we can combine them with authentication and permissions in Django, Django REST framework, and RESTful Web Services. We will analyze the throttling classes included in Django REST framework out of the box. We will follow the necessary steps to configure many throttling policies in Django REST framework. We will work with global and scope-related settings. Then, we will use command-line tools to compose and send many requests to test how the throttling rules work. We will understand versioning classes and we will configure a URL path versioning scheme to allow us to work with two versions of our RESTful Web Service. We will use command-line tools and the Browsable API to understand the differences between the two versions.

Chapter 19, Automating Tests, shows how to automate tests for our RESTful Web Services developed with Django and Django REST framework. We will use different packages, tools, and configurations to perform tests. We will write the first round of unit tests for our RESTful Web Service, run them, and measure tests code coverage. Then, we will analyze tests code coverage reports and write new unit tests to improve the test code coverage. We will understand the new tests code coverage reports and learn the benefits of a good test code coverage.

Chapter 20, Solutions, the right answers for the Test Your Knowledge sections of each chapter are included in the appendix.

Chapter 21, Templates, walks us through Django template language constructs, explaining its design choices, suggests how to organize template files, introduces handy template patterns, and points to several ways Bootstrap can be integrated and customized.

Chapter 22, Admin Interface, focuses on how to use Django's brilliant out-of-the box admin interface more effectively and several ways to customize it, from enhancing the models to toggling feature flags.

Chapter 23, Forms, illustrates the often confusing form workflow, different ways of rendering forms, improving a form's appearance using crispy forms, and various applied form patterns.

Chapter 24, Working Asynchronously, tours various asynchronous solutions for the Django developer, from the feature-rich Celery task queues, Python 3's asyncio, to the brand new Channels, and compares them for you.

Chapter 25, Creating APIs, explains RESTful API design concepts with practical advice on topics such as versioning, error handling, and design patterns using the Django REST framework.

Chapter 26, Security, familiarizes you with various web security threats and their counter measures, specifically looking at how Django can protect you. Finally, a handy security checklist reminds you of the commonly overlooked areas.

Chapter 27, Production-Ready, is a crash course in deploying a public-facing application beginning with choosing your webstack, understanding hosting options, and walking through a typical deployment process. We go into the details of monitoring and performance at this stage.

You will just need a computer (PC or Mac) and internet connectivity to start with. Then, ensure that the following are installed:

http
  .formLogin()
    .loginPage("/login")
     .failureUrl("/login?error")
      .and()
    .authorizeRequests()
      .antMatchers("/signup","/about").permitAll()
      .antMatchers("/admin/**").hasRole("ADMIN")
      .anyRequest().authenticated();

sudo apt-get install openjdk-8-jdk -y
java -version

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