In Chapter 19.17 of our e-book course, we'll cover one of the most crucial aspects of systems development with Python and Django: creating forms and deploying a Django application. Django is a high-level framework, written in Python, that promotes fast, clean and pragmatic development.
Forms in Django
Forms are an integral part of any web application. Django provides a powerful and flexible way to manage forms, from simply creating an HTML form to integrating with database templates.
To create a form in Django, we start by defining a form as a class, which is a subclass of django.forms.Form. Each class attribute represents a form field, each field is represented by an instance of a field class - CharField for character fields, DateTimeField for dates and times, etc. Django uses these classes to create the necessary HTML for the form and to validate user-submitted data when the form is submitted.
Form validation
Validation is a critical part of handling forms, and Django provides several tools to make this task easier. Each form field has a specific method for validation, which can be overridden if we need custom validation logic. Additionally, each form has an is_valid() method, which performs all field validations and returns True if all data is valid.
Rendering forms
After defining and validating a form, we need to render it in a template. Django provides several ways to do this, from manually rendering each field to automatically rendering the entire form with the as_p() method.
Deploying a Django application
Once our system is ready and tested, the next step is to put it into production, that is, make it accessible to users on the web. This process is known as deploy.
Choosing a server
The first step in deploying a Django application is choosing where it will be hosted. There are many hosting services available, each with its own pros and cons. Some are specific to Python and Django, like Heroku and PythonAnywhere, while others, like Amazon AWS and Google Cloud, offer a broader range of services.
Configuring the server
After choosing a server, we need to configure it to host our application. This involves installing Python and Django, setting up the web server (such as Apache or Nginx), setting up the database, and configuring Django to use these services.
Downloading the application
Once the server is configured, we can transfer our application to it. This usually involves copying all of our application's files to the server and running any commands needed to start the application (such as python manage.py runserver).
Maintenance and monitoring
Once our application is in production, we will need to monitor it to ensure that it is working properly and to do any necessary maintenance. Django provides several tools to help with this, including a robust logging system and the ability to send email notifications in case of errors.
In summary, Django offers a number of powerful features that make creating complex systems a much more manageable task. With practice and experience, you'll find that you can create robust and efficient web applications with relative ease.
