Django messages framework

Introduction:

The Django framework already provides all the necessary implementations to enable the messages framework. The default settings created by using django-admin startproject already contain all the settings needed to enable message functionality.

You can find django.contrib.messages in INSTALLED_APPS in your settings.py configuration file.

The necessary middleware will also be added: django.contrib.sessions.middleware.SessionMiddleware and django.contrib.messages.middleware.MessageMiddleware. The default storage backend relies on sessions, so the SessionMiddleware must be enabled.

And at last the context_processors option of the DjangoTemplates backend defined in your settings.py configuration file contains django.contrib.messages.context_processors.messages.

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In order to customise the message tags and to use the message alerts of Bootstrap 5.3, the variable MESSAGE_TAGS is overwritten in the following way:

# settings.py

from django.contrib.messages import constants as messages


# for django messages framework:
MESSAGE_TAGS = {
    messages.DEBUG: "alert-secondary",
    messages.INFO: "alert-info",
    messages.SUCCESS: "alert-success",
    messages.WARNING: "alert-warning",
    messages.ERROR: "alert-danger",
}

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Create a template that iterates over the messages and displays them as needed to display them on your website.

# messages.html

<div class="mt-4" style="width: 95%; padding-top: 40px;">
  {% if messages %}
    <ul class="messages">
      {% for message in messages %}
        <div class="container-fluid p-0">
          <div class="alert {{ message.tags }} alert-dismissible" role="alert" >
            <button type="button" class="btn-close" data-bs-dismiss="alert" aria-label="Close"></button>
            {{ message }}
          </div>
        </div>
      {% endfor %}
    </ul>
  {% endif %}
</div>

Due to the Bootstrap implementation, this template is customised.

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You will need to add the messages.html ({% include 'messages.html' %}) template to the base layout because I have created a separate messages template.

# base.html

 <!-- End of Navbar -->

 <!-- Alert/Messages -->
 {% include 'messages.html' %}
 <!-- End of Alert/Messages -->

 {% block content %}
 {% endblock %}

I have chosen to display the messages under the navbar and before the block content of the website.

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The last important part is to create messages in your view. If you don't create any messages (error, info, success, etc) in your view, you won't see any messages.

# views.py

from django.contrib import messages

def login_page_view(request):
    form = LoginForm()
    if request.method == 'POST':
        form = LoginForm(request.POST)
        if form.is_valid():
            user = authenticate(
                username=form.cleaned_data['username'],
                password=form.cleaned_data['password'],
            )
            if user is not None:
                login(request, user)
                return redirect('review:feeds_page')

            else:
                messages.error(request, "Invalid username or password!")

    return render(request, 'login_page.html', context={'form': form})

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• official Django documentation about the messages framework
• official Bootstrap documentation for the messages alerts