Manually calling a class based generic view in Django - python

I'm currently trying to call a class based Generic view from within another class based generic view and cant seem to do it correctly.
Ways I've tried:
result = CategoryTypes.as_view() # The same way you put it in the urlconf
print result
Prints: <function CategoryTypes at 0x92bd924>
CategoryTypes.as_view()(self.request)
# &
CategoryTypes().dispatch(self.request)
Tracebacks:
ContentNotRenderedError at /crm/categories/company/ The response content must be rendered before it can be accessed.
result = CategoryTypes().__init__()
print result
Prints: None
How do I call this from another view? I've seriously tried every method in the class and way of calling it I can think of.

The first way -- CategoryTypes.as_view()(self.request) -- is right. The problem is that if your view returns a TemplateResponse, its render method isn't called automatically.
So if you need to access the content of the response, call render() on it first.

Or you can directly access just content via result.rendered_content. Before making this be sure you will set session into your request before passing into a view:
self.request.session = {}
CategoryTypes.as_view()(self.request)

Related

Get all parameters and their values in a request in Django [duplicate]

I am currently defining regular expressions in order to capture parameters in a URL, as described in the tutorial. How do I access parameters from the URL as part the HttpRequest object?
My HttpRequest.GET currently returns an empty QueryDict object.
I'd like to learn how to do this without a library, so I can get to know Django better.
When a URL is like domain/search/?q=haha, you would use request.GET.get('q', '').
q is the parameter you want, and '' is the default value if q isn't found.
However, if you are instead just configuring your URLconf**, then your captures from the regex are passed to the function as arguments (or named arguments).
Such as:
(r'^user/(?P<username>\w{0,50})/$', views.profile_page,),
Then in your views.py you would have
def profile_page(request, username):
# Rest of the method
To clarify camflan's explanation, let's suppose you have
the rule url(regex=r'^user/(?P<username>\w{1,50})/$', view='views.profile_page')
an incoming request for http://domain/user/thaiyoshi/?message=Hi
The URL dispatcher rule will catch parts of the URL path (here "user/thaiyoshi/") and pass them to the view function along with the request object.
The query string (here message=Hi) is parsed and parameters are stored as a QueryDict in request.GET. No further matching or processing for HTTP GET parameters is done.
This view function would use both parts extracted from the URL path and a query parameter:
def profile_page(request, username=None):
user = User.objects.get(username=username)
message = request.GET.get('message')
As a side note, you'll find the request method (in this case "GET", and for submitted forms usually "POST") in request.method. In some cases, it's useful to check that it matches what you're expecting.
Update: When deciding whether to use the URL path or the query parameters for passing information, the following may help:
use the URL path for uniquely identifying resources, e.g. /blog/post/15/ (not /blog/posts/?id=15)
use query parameters for changing the way the resource is displayed, e.g. /blog/post/15/?show_comments=1 or /blog/posts/2008/?sort_by=date&direction=desc
to make human-friendly URLs, avoid using ID numbers and use e.g. dates, categories, and/or slugs: /blog/post/2008/09/30/django-urls/
Using GET
request.GET["id"]
Using POST
request.POST["id"]
Someone would wonder how to set path in file urls.py, such as
domain/search/?q=CA
so that we could invoke query.
The fact is that it is not necessary to set such a route in file urls.py. You need to set just the route in urls.py:
urlpatterns = [
path('domain/search/', views.CityListView.as_view()),
]
And when you input http://servername:port/domain/search/?q=CA. The query part '?q=CA' will be automatically reserved in the hash table which you can reference though
request.GET.get('q', None).
Here is an example (file views.py)
class CityListView(generics.ListAPIView):
serializer_class = CityNameSerializer
def get_queryset(self):
if self.request.method == 'GET':
queryset = City.objects.all()
state_name = self.request.GET.get('q', None)
if state_name is not None:
queryset = queryset.filter(state__name=state_name)
return queryset
In addition, when you write query string in the URL:
http://servername:port/domain/search/?q=CA
Do not wrap query string in quotes. For example,
http://servername:port/domain/search/?q="CA"
def some_view(request, *args, **kwargs):
if kwargs.get('q', None):
# Do something here ..
For situations where you only have the request object you can use request.parser_context['kwargs']['your_param']
You have two common ways to do that in case your URL looks like that:
https://domain/method/?a=x&b=y
Version 1:
If a specific key is mandatory you can use:
key_a = request.GET['a']
This will return a value of a if the key exists and an exception if not.
Version 2:
If your keys are optional:
request.GET.get('a')
You can try that without any argument and this will not crash.
So you can wrap it with try: except: and return HttpResponseBadRequest() in example.
This is a simple way to make your code less complex, without using special exceptions handling.
I would like to share a tip that may save you some time.
If you plan to use something like this in your urls.py file:
url(r'^(?P<username>\w+)/$', views.profile_page,),
Which basically means www.example.com/<username>. Be sure to place it at the end of your URL entries, because otherwise, it is prone to cause conflicts with the URL entries that follow below, i.e. accessing one of them will give you the nice error: User matching query does not exist.
I've just experienced it myself; hope it helps!
These queries are currently done in two ways. If you want to access the query parameters (GET) you can query the following:
http://myserver:port/resource/?status=1
request.query_params.get('status', None) => 1
If you want to access the parameters passed by POST, you need to access this way:
request.data.get('role', None)
Accessing the dictionary (QueryDict) with 'get()', you can set a default value. In the cases above, if 'status' or 'role' are not informed, the values ​​are None.
If you don't know the name of params and want to work with them all, you can use request.GET.keys() or dict(request.GET) functions
This is not exactly what you asked for, but this snippet is helpful for managing query_strings in templates.
If you only have access to the view object, then you can get the parameters defined in the URL path this way:
view.kwargs.get('url_param')
If you only have access to the request object, use the following:
request.resolver_match.kwargs.get('url_param')
Tested on Django 3.
views.py
from rest_framework.response import Response
def update_product(request, pk):
return Response({"pk":pk})
pk means primary_key.
urls.py
from products.views import update_product
from django.urls import path
urlpatterns = [
...,
path('update/products/<int:pk>', update_product)
]
You might as well check request.META dictionary to access many useful things like
PATH_INFO, QUERY_STRING
# for example
request.META['QUERY_STRING']
# or to avoid any exceptions provide a fallback
request.META.get('QUERY_STRING', False)
you said that it returns empty query dict
I think you need to tune your url to accept required or optional args or kwargs
Django got you all the power you need with regrex like:
url(r'^project_config/(?P<product>\w+)/$', views.foo),
more about this at django-optional-url-parameters
This is another alternate solution that can be implemented:
In the URL configuration:
urlpatterns = [path('runreport/<str:queryparams>', views.get)]
In the views:
list2 = queryparams.split("&")
url parameters may be captured by request.query_params
It seems more recommended to use request.query_params. For example,
When a URL is like domain/search/?q=haha, you would use request.query_params.get('q', None)
https://www.django-rest-framework.org/api-guide/requests/
"request.query_params is a more correctly named synonym for request.GET.
For clarity inside your code, we recommend using request.query_params instead of the Django's standard request.GET. Doing so will help keep your codebase more correct and obvious - any HTTP method type may include query parameters, not just GET requests."

Unittest sensitive_post_parameters decorator in django view

I have a view to create new users in my django project.
I am applying the #sensitive_post_parameters decorator to that view to make sure the password isn't logged if there is an unhandled exception or something like that (as indicated in the comments in the source code https://docs.djangoproject.com/en/2.0/_modules/django/views/decorators/debug/).
When I proceed to test the view, I would like to make sure that this protection of the sensitive information is still in place (that I didn't delete the decorator to the function by mistake or something).
I am aware, since the decorator is applied to my function, I can't test it directly from the view tests.
But, for example, with the #login_required decorator, I can test its effects with assertRedirects (as explained here How to test if a view is decorated with "login_required" (Django)).
I have been searching for a way to do that, but I can't find one that works.
I thought of something like this:
def test_senstive_post_parameters(self):
request = RequestFactory().post('create_user', data={})
my_sensitive_parameters = ['password']
self.assertEqual(
request.sensitive_post_parameters,
my_senstive_parameters
)
but that gives me an
AttributeError: 'WSGIRequest' object has no attribute 'sensitive_post_parameters'
Any help would be appreciated.
Even it is telling me I shouldn't be attempting to test this, though I would really like to, as it is seems like an important behaviour that I should make sure remains in my code as it is later modified.
You have created a request using RequestFactory, but you have not actually used it. To test the effect of your view you need to import the view and call it.
from myapp.views import create_user
def test_senstive_post_parameters(self):
request = RequestFactory().post('create_user', data={})
response = create_user(request)
my_sensitive_parameters = ['password']
self.assertEqual(
request.sensitive_post_parameters,
my_senstive_parameters
)

Exposing global data and functions in Pyramid and Jinja 2 templating

I have a base template for when a user is logged in, and on that base template, I need to add user specific options in a drop down menu. This drop down menu with options must be constant across all handlers, i.e., any time the base template is invoked (extended) with a child template.
Other than performing the necessary DB query, assigning the query results to a variable, and passing that variable to every handler (there are many), how can I consolidate this into one query and one variable, which gets passed directly to the base template? I am using jinja2 templates as well.
I would hate to do something so cumbersome in exchange for something far more simple and maintainable.
Any ideas? Thanks.
EDIT
So I still haven't found anything that's exactly what I'm looking for; however, I decided to at least make some headway in the interim. So, I made a custom decorator that takes a view's returned dict() and appends the appropriate data to it. For example:
def get_base_data(func):
def wrapper(request):
d = func(request)
user_id = request.user.id # used in query
contact_group_data = ContactGroups.query.filter(...criteria...).all()
d['contact_group_data'] = contact_group_data
return d
return wrapper
Now, I can at least decorate each method very concisely and simply by putting:
#view_config(...)
#get_base_data
def my_handler(request):
pass # rest of code...
This is one of most inobvious things in Pyramid and took a while to find for me, too.
You can modify the global template context in BeforeRender event.
http://docs.pylonsproject.org/projects/pyramid/en/latest/narr/hooks.html#using-the-before-render-event
Alternatively, you could use class based views, inherit all your views from one base view class which has get_base_data(), then the class instance is passed to the template context to all your views and then you could extract the data with {{ view.get_base_data }}.
http://ruslanspivak.com/2012/03/02/class-based-views-in-pyramid/
I vouch for the latter approach as it is more beautiful, predictable and easier to maintain engineering wise.

Python, Django, how to use getattr (or other method) to call object that has multiple attributes?

After trying to get this to work for a while and searching around I am truly stumped so am posting here... I want to make some functions in classes that I am writing for django as generic as possible so I want to use getattr to call functions such as the one below in a generic manner:
the way I do it that works (non-generic manner):
from django.db.models import get_model
mymodel = get_model('appname', 'modelname')
dbobject = mymodel.objects.all()
one of my attempts create this in a generic manner, still not working, it does return something back but its not the proper object type so that i can get the data from it (its a database call for django)
ret = getattr(mymodel,'objects')
dbobject = getattr(ret,'all')
You forgot to call the result.
dbobject = mymodel.objects.all()
Accesses the method mymodel.objects.all and then calls it.
ret = getattr(mymodel,'objects')
self.dbobject = getattr(ret,'all')
accesses the method mymodel.objects.all but does not call it.
All you need is to change the last line to:
self.dbobject = getattr(ret,'all')()
You will need to call the attribute if it's a function, e.g.
ret = getattr(mymodel,'objects')
all = getattr(ret,'all')
self.dbobject = all()

Django: how to retrieve an object selected by the ``object_detail`` generic view?

Hi (sorry for my ugly english)
I wonder if this is possible to retrieve an object which was selected with the object_detail generic view. For example :
from django.views.generic.list_detail import object_detail
def my_view(request, slug)
response = object_detail(request, MyModel.objects.all(),
slug=slug,
slug_field='slug',
template_object_name='object')
# Here I need my object in ``response`` to do something after.
I don't know where is the object
You can't get the object this way, since object_detail simply returns a rendered response. If you need it, you'll just have to get it manually:
object = MyModel.objects.get(slug=slug)

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