Django generic login view creates variable automatically?

StackOverflow https://stackoverflow.com/questions/21081645

Question

I am using the django generic login view. This is my urls.py

from django.contrib.auth.views import login
....
url(r'^login/$', login),

This is my login.html page:

<body>
<h1>User Login</h1>

{% if form.errors %}
    <p>Your username and password did not match. 
    Please try again.</p>
{% endif %}
<form method="post" action="">{% csrf_token %}
    <p><label for="id_username">Username:</label>
    {{ form.username }}</p>

    <p><label for="id_password">Password:</label>
    {{ form.password }}</p>

    <input type="hidden" name="next" />
    <input type="submit" value="login" />
</form>
</body>

This is the generic login view:

def login(request, template_name='registration/login.html',
      redirect_field_name=REDIRECT_FIELD_NAME,
      authentication_form=AuthenticationForm,
      current_app=None, extra_context=None):
"""
Displays the login form and handles the login action.
"""
redirect_to = request.REQUEST.get(redirect_field_name, '')
if request.method == "POST":
    form = authentication_form(data=request.POST)
    if form.is_valid():

        # Ensure the user-originating redirection url is safe.
        if not is_safe_url(url=redirect_to, host=request.get_host()):
            redirect_to = resolve_url(settings.LOGIN_REDIRECT_URL)

        # Okay, security check complete. Log the user in.
        auth_login(request, form.get_user())

        if request.session.test_cookie_worked():
            request.session.delete_test_cookie()

        return HttpResponseRedirect(redirect_to)
else:
    form = authentication_form(request)

request.session.set_test_cookie()

current_site = get_current_site(request)

context = {
    'form': form,
    redirect_field_name: redirect_to,
    'site': current_site,
    'site_name': current_site.name,
}
if extra_context is not None:
    context.update(extra_context)
return TemplateResponse(request, template_name, context,
                        current_app=current_app)

Now, Once I successfully log in, it redirects me to the homepage since in my settings.py, 

LOGIN_REDIRECT_URL='/'

This is my homepage view:

def main_page(request):
variables = {
 'head_title': 'Django Bookmarks',
'page_title': 'Welcome to Django Bookmarks',
'page_body': 'Where you can store and share bookmarks!',   
}
return render(request, 'main_page.html', variables)

and this is my homepage template (main_page.html):

<body>
{% if user.username %}
    <p>Welcome {{ user.username }}</p>
{% else %}
<p>Welcome unknown user, please <a href='/login'>Login</a> in order to get full access to the website.</p>
{% endif %}
<h1>{{ page_title }}</h1>
<p>{{ page_body }}</p>
</body>

Now, for some reason, the 

{% if user.username %}

line executes to true after I sign the user in, even though in my homepage view, I didn't even create a 'user' variable / object. I'm wondering, where exactly is the variables 'user' created and how is it being sent as a variables to my main_page.html template?

Was it helpful?

Solution

The user variable is injected by a context processor of the auth module.

See source

OTHER TIPS

That is the AuthenticationMiddleware assigning request.user (guaranteed to be one of User or AnonymousUser), then the auth context processor exposes request.user to the template and it's permissions as user, perms.

Licensed under: CC-BY-SA with attribution
Not affiliated with StackOverflow
scroll top