id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
12329	"""template"" view decorator, allows to completely isolate views from templates"	gurunars	nobody	"Well, the key point of this decorator is to let the developer define a template for the view in the following way:

{{{
@template
def view_name(request):
    ...
}}}

OR

{{{
@template(""template_name"")
def view_name(request):
    ...
}}}

In the first case the decorator automatically composes template's name in the following way: ""app_name/view_name.html"". This is the same name you would use in a ""render_to_response"" shortcut function.

In the second case you define template's name explicitly. Again use the same name you would use for the ""render_to_response"" shortcut function.

In both cases the return type can be either a dictionary, an HttpResponse or an HttpResponseHolder. The last one is just an extension to HttpResponse base class - it has just a single additional parameter called ""context"" (it is a dictionary). The only purpose of HttpResponseHolder is to pass a context dictionary to some other decorators for further processing. What kind of processing? I will give some examples below.

'''First''' example is quite trivial. How to pass the ""MEDIA_PATH"" parameter from ""settings.py"" to all the templates? In this case it is really simple - use a decorator as the one just below 

{{{
from django.conf import settings
from .template import *

class media(object):

    def __init__(self, orig_func):
        self.orig_func = orig_func
        #to compose template's name properly
        self.__name__ = self.orig_func.__name__
        self.__module__ = self.orig_func.__module__

    def __call__(self, *args, **kwargs):
        return_val = self.orig_func(*args, **kwargs)
        if isinstance(return_val, HttpResponseHolder):
            return_val.context[""MEDIA_URL""] = settings.MEDIA_URL
        elif isinstance(return_val, dict):
            return_val[""MEDIA_URL""] = settings.MEDIA_URL
        return return_val
}}}

in chain with the ""template"" decorator

{{{
@template()
@media
def view_name(request):
    ...
}}}

'''Second''' example is little bit more sophisticated but useful. How to pass to the template information about the user that is currently logged in (user object)? Use the following decorator

{{{
from .template import * #HttpResponseHolder

class user(object):

    def __init__(self, orig_func):
        self.orig_func = orig_func
        #to compose template's name properly
        self.__name__ = self.orig_func.__name__
        self.__module__ = self.orig_func.__module__

    def __call__(self, request, *args, **kwargs):
        return_val = self.orig_func(request, *args, **kwargs)
        if request.user:
            if isinstance(return_val, HttpResponseHolder):
                return_val.context[""user""] = request.user
            elif isinstance(return_val, dict):
                return_val[""user""] = request.user
        return return_val
}}}

again in chain with the ""template"" decorator

{{{
@template()
@user
def view_name(request):
    ...
}}}

Definitely, writing your own decorators requires some skills in Python. But once done they simplify your life a lot. 


"		closed	Uncategorized	1.1		wontfix			Unreviewed	0	0	0	0	0	0