With the following renderer...
from django.shortcuts import render
...
return render(request, 'template.html', {'context':context,})
Is it possible to override the render classe's methods so that I can in certain circumstances interpret template tags myself for example if I find a tag consisting of a certain format such as...
{% url 'website' page.slug %}
I could point it to...
/theme/theme-1/page.html
or
/theme/theme-2/page.html
depending on extranious settings.
The render method is just a shortcut for:
template = loader.get_template(''template.html')
context = {
...,
}
return HttpResponse(template.render(context, request))
Therefore, it is not the correct place to try to change the behaviour of the url tag.
For the example you have given, it looks like the website should be a variable that holds theme-1 or theme-2. You can then pass the variable to the url tag instead of the string 'website'.
{% url website page.slug %}
If that is not possible, you could create a custom template tag my_url that returns the correct url depending on your settings.
Related
What is the recommended way to write views (as functions) in Django?
I am asking in terms of readability, etc.
For example: define the template first, then do the translations, then define models and lastly define context.
Here is some example code:
def index(request): # Landing page, translated to the browser's language (default is english)
template = loader.get_template("koncerti/index.html")
# Translators: This is the text on the homepage buttons
concerts = gettext("Koncerti")
band = gettext("Band")
# Translators: This is the option in the language-switch box
foreignLanguage = gettext("eng")
koncertiUrl = '/koncerti/international' # The URL slug leading to 'koncerti' page
bandUrl = '/band/international' # The URL slug leading to 'band' page
translationMode = '' # The URL slug that is leading to slovenian translation mode
context = {
'Concerts' : concerts,
'Band' : band,
'foreignLanguage' : foreignLanguage,
'koncertiUrl' : koncertiUrl,
'bandUrl' : bandUrl,
'translationMode' : translationMode
}
return HttpResponse(template.render(context, request))
I think you are doing too much in the view. A view is supposed to make the proper querysets, and make changes to the database. It's main task is thus to decide what to render, and what to update. Not how to update it.
Deciding about translations, url resolution, etc. is normally a task of the template. The template has template tags for that such as {% trans … %} [Django-doc] and {% url … %} [Django-doc].
Using the {% url … %} over raw URLs you construct yourself is strongly advisable. It makes the odds of making a mistake smaller, and furthermore it is clear to what view you are referring.
You furthermore might want to use render(..) [Django-doc]. This function combines looking for a template, rendering that template with the template render engine, and returning a HTTP response.
from django.shortcuts import render
def index(request):
return render(request, 'koncerti/index.html', {})
In the template, you can then render this with:
{% load i18n %}
{% trans 'Koncerti' %}
I have a custom context processor that passes some server side constants to the client (by injecting into javascript object). Some views might want to add additional params, notifications for example, to the dict.
from django.contrib.sites.shortcuts import get_current_site
def client_context(request):
params = {}
domain = get_current_site(request).domain
schema = request.scheme
params['rooturl'] = "%s://%s" % (schema,domain)
return {'params': params}
According to the docs
When context processors are applied
Context processors are applied after the context itself is processed. This means that a context processor may overwrite variables you’ve supplied to your Context or
RequestContext, so take care to avoid variable names that overlap with
those supplied by your context processors.
If I render a template without overriding params it's working fine - i get the baseurl in the template.
If I render the template with a variable named params i get only the overrided value.
def home(request):
return render(request, 'home.html', { 'params' : {'page' : 'home'} })
so i have two questions
Is the django docs incorrect ? from what i understand the second
dict should update the first one. According to these findings my
custom context is applied first.
What is the best way to achieve this ?
EDIT
In my base.html file (extended by all other templates) i pass the params object to a Js objects. e.g
{% block init %}
<script>
Global = new Global( {{ params | json }} );
</script>
{% endblock %}
I was hoping for a solution that wont require adding each possible parameter by name
{% block init %}
<script>
Global = new Global( { baseurl : "{{baseurl}}", page : "{{ page }}" );
</script>
{% endblock %}
Django is working as documented. The params returned by your template context processor is overwriting the params in the view's context. Django doesn't automatically merge dictionaries as you want.
Instead of using the render shortcut, you could make your views return TemplateResponse objects. Then, instead of writing a context processor, write a middleware that updates the params dict in the process_template_response method.
In my Django URLs, I have many URL patterns that end with :
(redirect/(?P<redirect_to>\w+))
Which means that these URLs can be (or not) ending by /redirect/TARGET/. These URL patterns have other named arguments (mostly one : pk)
Now, I'd like, in the templates used by these URL patterns, to be able to alter the current page path, by just adding the redirect_to argument, and keeping the other arguments and URL reverse name untouched.
I was able to get the URL reverse name in the template, by adding resolve(path).url_name to the current context, and then to use that with the {% url %} template tag.
I'd like to know if there is any easy way to dynamically add the arguments (from resolve(path).kwargs) to the URL reverse tag ?
I think you should create a custom tag for this (replacing your {% url %} tag with {% url_redirect "your_new_destination" %}).
in your_app/templatetags/my_custom_tags.py:
from django.core.urlresolvers import reverse, resolve
#register.simple_tag(takes_context=True)
def url_redirect(context, new_destination):
match = resolve(context.request.path)
match.kwargs['redirect_to'] = new_destination
return reverse(match.url_name, args=match.args, kwargs=match.kwargs)
in your template:
{% load my_custom_tags %}
{% url_redirect "your_new_destination" %}
Please note that you need to add 'django.core.context_processors.request' to your TEMPLATE_CONTEXT_PROCESSORS in order for this snippet to work.
I have a url defined as follows:
url(r'^details/(?P<id>\d+)$', DetailView.as_view(), name='detail_view'),
In my templates, I want to be able to get the following url: /details/ from the defined url.
I tried {% url detail_view %}, but I get an error since I am not specifying the id parameter.
I need the url without the ID because I will be appending it using JS.
How can I accomplish this?
Just add this line to your urls.py:
url(r'^details/$', DetailView.as_view(), name='detail_view'),
or:
url(r'^details/(?P<id>\d*)$', DetailView.as_view(), name='detail_view'),
(This is a cleaner solution - thanks to Thomas Orozco)
You'll need to specify that id is optional in your view function:
def view(request, id=None):
I am trying to put a login form in every page in my web that uses django.contrib.auth.views.login. I created a templatetag in templatetags/mytags.py, where I define a function called get_login wich looks like this:
#register.inclusion_tag('registration/login.html', takes_context=True)
def get_login(context):
...
return {'formLogin': mark_safe(AuthenticationForm())}
...and in base.html:
{% load mytags %}{% get_login %}
The problem now is that the template (registration/login.html) doesnt recognize {{ formLogin.username }},{{ formLogin.password }}... and so on.
What am I missing?
mark_safe returns an instance of django.utils.safestring.SafeString, not a form, so those lookups will fail. I don't think there's anything wrong with directly returning the form (that's what all the generic views in django.contrib.auth do when populating templates, for instance). Just change your return statement to
return {'formLogin': AuthenticationForm()}
and it should work.