WEB 1.1 - Module 2: Lesson 2

Learning Outcomes 💫

By the end of this lesson, you should be able to...

• Explain how named parameters can be used in place of a context dictionary to pass key-value pairs to a template.

Exercises 💪

No exercises for this one, but if you want, try refactoring the previous exercise(s) to use named parameters instead of a context dictionary!

Written Guide 🗒

<aside> 🤔 Wouldn't it sometimes be a better practice to pass in an entire key-value pair as a parameter instead of the context object? This could help in situations where the context object gets defined dynamically (i.e. we don't know the context values before run time)!

</aside>

# a Python route that returns a rendered template
def submit_pizza():
    context = {
        'users_email': request.args.get('email'),
        'users_phone': request.args.get('phone'),
        'crust_type': request.args.get('crust'),
        'pizza_size': request.args.get('size')
    }
		
		# this code returns a template of HTML instead of plain text
    return render_template('submission_page.html', **context)

Fig 1 - a previous example from the Templates lesson that passes in a context object

<aside> 💡 Since we pass the context object to render_template() using the **kwargs syntax, we could also pass in a series of key-value pairs defined as parameters as in Fig 2.

</aside>

This example gives exactly the same result as the previous example.

def submit_pizza():
    return render_template('submission_page.html',
        users_email=request.args.get('email'),
        users_phone=request.args.get('phone'),
        crust_type=request.args.get('crust'),
        pizza_size=request.args.get('size'))

Fig 2 - using named parameters to pass in values in place of a context object