Django shortcuts module is a collection of helper functions that are generally used in view function/classes. There are many shortcuts available in module django.shortcuts. In other words, these function /classes introduce controlled coupling for convenience’s sake.
render()
It combines a given template with a dictionary and returns the HttpResponse object with that rendered text. Following is the syntax of the render() function.
Syntax –
render(request, template_name, context=None, content_type=None, status=None, using=None) Parameters –
Below are the parameters of render() function.
- request – It is used to generate the response.
- template_name – It takes the template names and display the template contents.
Optional Parameters –
- context – It represents the dictionary of values to add to the template context.
- content_type – The MIME type to use for the resulting document. Default to ‘text/html’.
- status – It shows the status code for the response. Defaults to 200.
- using – The name of a template engine to use for loading the template.
Example – In the following example, we render the template newapp/index.html.
- from django.shortcuts import render
- def new_view(request):
- # View code here...
- return render(request, 'newapp/index.html', {
- 'foo': 'bar',
- }, content_type='application/xhtml+xml')
It is equivalent to the below code.
def new_view(request):
# View code here...
t = loader.get_template('newapp/index.html')
c = {'foo': 'bar'}
return HttpResponse(t.render(c, request), content_type='application/xhtml+xml')redirect()
The redirect() function is used to redirect to the specific URL. It returns an HttpResponseRedirect to the appropriate URL for the argument passed. Let’s see the following syntax.
Syntax –
redirect(to, *args, permanent=False, **kwargs)Parameters –
- A model: The model’s get_absolute_url() function will be called.
- A view name with arguments: urls.reverse() will be used to reverse-resolve the name.
- A URL will be used as-is for the redirect location.
Example –
def blog_view(request, post_id):
blog = Post.objects.get(pk=post_id)
return redirect(blog)
# equivalent to: return HttpResponseRedirect(blog.get_absolute_url())
def blog_view(request, post_id):
return redirect('blog_details', id=post_id)
# equivalent to: return HttpResponseRedirect(reverse('blog_details', args=(post_id, )))
def relative_url_view(request):
return redirect('/blogs/archive/')
# equivalent to: return HttpResponseRedirect('/blogs/archive/')By default, the redirect() returns a temporary redirect. However, we can returns the permanent redirect if set to True.
def my_view(request):
obj = MyModel.objects.get(...)
return redirect(obj, permanent=True)get_object_or_404()
It returns the DoesNotExist exception if the searched object is not found. On the other hand, get() method raise Http404.
Parameters
- Klass – A Model class, a Manager, or a QuerySet instance from which to get the object.
- from django.shortcuts import get_object_or_404
- def my_view(request):
- obj = get_object_or_404(MyModel, pk=1)
*kwargs - Lookup parameters, which should be in the format accepted by get() and filter().Let’s understand the below example.
Example –
It is equivalent to:
- from django.http import Http404
- def my_view(request):
- try:
- obj = MyModel.objects.get(pk=1)
- except MyModel.DoesNotExist:
- raise Http404("No MyModel matches the given query.")
get_list_or_404()
It returns the results of filter() on a given model manager cast to a list, raising Http404 if the resulting list is empty. The syntax is same as get_object_or_404.
Parameters
- klass – A Model, Manager or QuerySet instance from which to get the list.
- **kwargs – Lookup parameters, which should be in the format accepted by get() and filter().
Let’s understand the following example.
Example –
from django.shortcuts import get_list_or_404
def my_view(request):
my_objects = get_list_or_404(MyModel, published=True)It is equivalent to:
from django.http import Http404
def my_view(request):
my_objects = list(MyModel.objects.filter(published=True))
if not my_objects:
raise Http404("No MyModel matches the given query.")We have discussed a few important shortcuts that provide control over the objects. These shortcuts also allow handling the potential errors effectively.
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