I am beginner in web development with Django. I have noticed that the locals() function is used instead of the context dictionary that I am used to see.
From what I see on the internet locals() is pretty useful, so are there any special cases where this is not true and its better to use the context_dictionary?
Using locals() in that tutorial is just for convenience, since all the data he needs to pass to the template is stored in local variables. locals() returns a dictionary holding the local variables names (as keys) and the current values (as values).
You need to use an explicit context_dictionary, instead of passing locals(), if you must build your data and you don't have such data in separate variables.
both locals() and context_dictionary are dictionaries, and that's the only requirement: a dictionary-like object (i.e. an object supporting __getitem__(key) and get(key, default=None) methods). How you get the dictionary, is up to you. There's no practice about that, but alternatives are:
RequestContext(), which is a dict-like object, if you use CONTEXT_PROCESSORS.locals() if you have the data in your local variables.EDIT - Examples:
Example on building the dictionary on your own:
def my_view(request):return render_to_response('hello.html', {'full_name': u"%s %s" % (request.user.first_name, request.user.last_name),'username': request.user.username})
Example on building the dictionary from locals():
def my_view(request):full_name = u"%s %s" % (request.user.first_name, request.user.last_name)username = request.user.usernamereturn render_to_response('hello.html', locals())
Assume hello.html is - in either case:
<html><body>You are {{ full_name }} ({{ username }})</body>
</html>
You'll get the expected result.