I have a view method with two additional parameters:
def foo(request, email, token):
...
And I need to use reverse to generate a URL:
...
url = urlresolvers.reverse(
'my_app.views.foo',
kwargs={ 'token': <token>, 'email': <email> })
Is my use of reverse reasonable/acceptable, and
What does the URL pattern for foo look like?
1 - Yes, as far as it goes, but of course it will fail without the urlpattern. You can use either args or kwargs, depending on your case. Here you can use args, as they are both required args from your view function.
2 - Here's a urlpattern to get you going, but the regex is only an example, as I don't know what your regex needs to be.
url(r'^/(?P<email>[-\w]+)/(?P<token>\d{1,2})/$', 'views.foo', name='foo'),
Named urls are a good pattern to get into the habit of doing. You can pass the name to the reverse function too:
url = urlresolvers.reverse(
'foo',
args=['<email>', '<token>']
Yes
It's up to you to write it in your URLconf.
You might want to have a look at Django docs
By your question, though, it's probably better if you run through the tutorial. The third part explains how to write down the URL scheme for your site.
Related
Say you have a url like this:
/cats/?filter=kittens
Is it possible to build a django url pattern that forces the use of the querystring?
Currently I have:
url(r'^/cats/$', views.CatsListView.as_view(), name='cats')
Now I want to add the querystring and get a different view, something like this:
url(r'^/cats/?filter=(?P<filter>.+?)$', views.CatsFilteredListView.as_view(), name='cats-filtered')
Is it possible to do something like this and still keep the querystring in the GET parameter of the request?
Remember that this is just a testcase, I, and you should too, know that filtering like probably this isn't the way to go..
Short answer: no, it's not possible. Django url patterns match only on the "path" componant of the url, period.
No, it's not possible to do this. If you really need two separate views, you can write a view that dispatches the correct view.
def cat_list_view(request, *args, **kwargs):
if 'filter' in request.GET:
return cat_list_filter_view(request, *args, **kwargs)
else:
return cat_list_unfiltered_view(request, *args, **kwargs)
However, for your example of CatsListView and CatsFilteredListView there is probably a better way to combine the views. For example you might be able to do the filtering in the get_queryset method.
While it is true that you cannot manipulate the path component like that, you can pass a dictionary in. It's a 3rd unnamed argument.
This approach can be useful if you want to use the same view for multiple resources, and pass data to configure its behaviour in each case (below we supply a different template in each case).
path('url/', views.my_reused_view, {'my_template_name': 'some_path'}, name='aurl'),
path('anotherurl/', views.my_reused_view, {'my_template_name': 'another_path'}, name='anotherurl'),
Note: Both extra options and named captured patterns are passed to the view as named arguments. If you use the same name for both a captured pattern and an extra option then only the captured pattern value will be sent to the view (the value specified in the additional option will be dropped).
Courtesy of https://developer.mozilla.org/en-US/docs/Learn/Server-side/Django/Generic_views
There is urls.py pattern.
url(r'^notice/(?P<article>[0-9]\d+)/', web.views.notice),
Here is views.py
def notice(request, article):
data = article
return render(request, "notice.html")
However, web brower shows 404 Error.
If I remove add parameter, it is ok.
What I am wrong?
Intended result (Blog style, not get parameter)
/notice/1, /notice/2, ...
I think what is happening is that [0-9]\d+ is expecting at least a 2-digit number, one digit for the [0-9] and then one or more digits following that due to the \d+. I believe what you really want is just
url(r'^notice/(?P<article>\d+)$', 'web.views.notice')
I don't know why you use d???
url(r'^issue/(?P<issue_id>[0-9]+)$', views.issue, name='issue'),
url(r'^project/(?P<pk>.*)$', login_required(views.ProjectView.as_view()), name='project'),
Based on the question you asked, I am getting that you want to display the data on the template based on the parameter passed in the URL.Let me try to explain it step by step:
First lets say you have the following url:
url(r'^notice/(?P<article>\d+)$', views.notice,name="notice")
Now lets define the view for fetching the data from the model, based on the parameter in the URL, i am assuming you are passing the PK in the URL:
def notice(request, article):
data = YourModelName.objects.get(id=article)
//Passing back the result to the template
context={"article":data}
return render(request, "notice.html",context)
Now in your template you can access the data as such:
{{ article.field_name }}
Hope this helps you out!!!!
Without using query strings (like ?case=/2/), nor captured parameters in the url conf (like ?P) (so they dont show up in the url),
is there a way to pass parameters to a view function when using URLs reverse resolution?
Hopefully an example will clarify my question:
With captured parameters I could do:
views.py
...
return HttpResponseRedirect(reverse('videos:show_details', args=[video.id]))
urls.py
...
url(r'^club/(?P\d+)/$',views.details, name='show_details'),
...
But what if the view details needs / accepts more parameters, for example:
def details (request, video_id, director='', show_all=True):
And we dont want them to show up in the url?
Any way of using args or kwargs without them being in the url?
Im sure Im missing something trivial here :S
Hopefully someone can point me in the right direction.
Thanks!
I'm not sure this is what you mean, but you can pass extra arguments to the url pattern. This allows multiple urls that point to the same view to use different arguments:
url(r'^club/(?P<pk>\d+)/$', views.details, kwargs={'show_all': False}, name='show_details')
N.B This question has been significantly edited before the first answer was given.
Hi,
I'm fairly new to django, so apologies if I'm missing something obvious.
I've got a urls.py file that looks like this:
urlpatterns = patterns(
'',
(r'^$', 'faros.lantern.views.home_page'),
(r'^login/$', 'django.contrib.auth.views.login'),
(r'^logout/$', 'django.contrib.auth.views.logout'),
(r'^about/$', 'faros.lantern.views.about_page_index', {}, 'about_page_index'),
(r'^about/(?P<page_id>([a-z0-9]+/)?)$', 'faros.lantern.views.about_page', {}, 'about_page'),
)
Views that looks like this:
def about_page_index(request):
try:
return render_to_response('lantern/about/index.html', context_instance=RequestContext(request))
except TemplateDoesNotExist:
raise Http404
def about_page(request, page_id):
page_id = page_id.strip('/ ')
try:
return render_to_response('lantern/about/' + page_id + '.html', context_instance=RequestContext(request))
except TemplateDoesNotExist:
raise Http404
And a template that includes this:
Contact
Contact
I'm getting this error message:
Caught an exception while rendering: Reverse for '<function about_page at 0x015EE730>' with arguments '()' and keyword arguments '{'page_id': u'contact'}' not found. The first reverse works fine (about_page_index), generating the correct URL without error messages.
I think this is because the request argument to the about_page view (request) is used, so I need to pass it in when I generate the URL in my template. Problem is, I don't know how to get to it, and searching around isn't getting me anywhere. Any ideas?
Thanks,
Dom
p.s. As an aside, does that method of handling static "about" type pages in an app look horrific or reasonable? I'm essentially taking URLs and assuming the path to the template is whatever comes after the about/ bit. This means I can make the static pages look like part of the app, so the user can jump into the about section and then right back to where they came from. Comments/Feedback on whether this is djangoic or stupid appreciated!
If I guess correctly from the signature of your view function (def about_page(request, page_id = None):), you likely have another URL configuration that points to the same view but that does not take a page_id parameter. If so, the django reverse function will see only one of these, and it's probably seeing the one without the named page_id regex pattern. This is a pretty common gotcha with reverse! :-)
To get around this, assign a name to each of the url patterns (see Syntax of the urlpatterns variable). In the case of your example, you'd do:
(r'^about/(?P<page_id>([a-z]+/)?)$', 'faros.lantern.views.about_page',
{}, 'about_with_page_id')
and then in the template:
Contact
Edit
Thanks for posting the updated urls.py. In the url template tag, using the unqualified pattern name should do the trick (note that I'm deleting the lantern.views part:
Contact
Contact
Edit2
I'm sorry I didn't twig to this earlier. Your pattern is expressed in a way that django can't reverse, and this is what causes the mismatch. Instead of:
r'^about/(?P<page_id>([a-z]+/)?)$'
use:
r'^about/(?P<page_id>[a-z0-9]+)/$'
I created a dummy project on my system that matched yours, reproduced the error, and inserted this correction to success. If this doesn't solve your problem, I'm going to eat my hat! :-)
I am currently defining regular expressions in order to capture parameters in a URL, as described in the tutorial. How do I access parameters from the URL as part the HttpRequest object?
My HttpRequest.GET currently returns an empty QueryDict object.
I'd like to learn how to do this without a library, so I can get to know Django better.
When a URL is like domain/search/?q=haha, you would use request.GET.get('q', '').
q is the parameter you want, and '' is the default value if q isn't found.
However, if you are instead just configuring your URLconf**, then your captures from the regex are passed to the function as arguments (or named arguments).
Such as:
(r'^user/(?P<username>\w{0,50})/$', 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."