URL Regular Expression mismatch - python

I am trying to learn Django and I am currently stuck in an issue.
I created an app Contact and run the server, I get the error.
The error page displayed by server:
The urls.py file in the app Contact
urls.py in conatct
When the pattern in urls.py is
urlpatterns =[url(r'^$', views.form, name ='form')]
it works properly, but not with other pattern shown in the picture
Your help would be greatly appreciated.

The Page not found error message tells you what went wrong: For the URL (/contact) you requested, Django was unable to find a suitable view. Because you have debugging enabled, you get some information, including a list of registered views.
First things first: You probably have url(r'^contact/', include('contact.urls')) somewhere in your top level urls.py. This makes the URLs defined in the contact/urls.py available under the prefix /contact.
With
urlpatterns = [
url(r'^form/', views.form, name='form'),
]
in contact/urls.py you are telling Django that you want urls starting with contact/form/ to be handled by views.form.
Consequently, when you access http://localhost:8000/contact/ in your browser, there is no view associated with that URL, hence the 404. Your view is reacting to to http://localhost:8000/contact/form, not http://localhost:8000/contact.
When you change the URL pattern to
urlpatterns = [
url(r'^$', views.form, name='form'),
]
you modify the URL views.form reacts to.

Related

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I have an issue where I try to go to my redirect page and get a NoReverseMatch when though the URL is there? Any idea how to fix this?
I have checked that the "schema" url works and it correctly supplies the openapi schema, but the other page simply can't understand the url.
URLS:
urlpatterns = [
path("schema/", SpectacularAPIView.as_view(), name="schema"),
# Optional UI:
path("docs/", SpectacularSwaggerView.as_view(url_name="schema"), name="swagger-ui"),
]
Errors:
For reverse url pathing, you have to use {% url api:schema %}. It's specified as namespace next to include('api.urls') or inside app urls, just above urlpatterns - like app_name = "api".

Django URL and Template with inbuilt authentication

I am a Django Beginner, I started by reading WS Vincent..The book created a customUser model in a separate App name USERS. Also, AUTH_USER_MODEL = 'users.CustomUser' has been set up. I have below question related to URLS and Templates . Any help will be appreciated
I have been reading that the Default Django login path will go to /accounts/login. However , when I used {% url login %} in template base.html it routed to users/login. That would be coz fo Auth_user_model, but I want to be sure how the above tag would fit in below URL's because there is still no accounts/login URL. If it is getting that from auth.urls package then it only has everything starting with /accounts not /user. I did a packet capture thinking it might be translating to account/login but destination was still users/login. .I hope I was able to explain my query. Please help.
urlpatterns = [
path('admin/', admin.site.urls),
path('users/', include('users.urls')), # new
path('users/', include('django.contrib.auth.urls')),# new
path('', TemplateView.as_view(template_name='home.html'),name='home'), # new
]
(if i understand your question correctly) there is a default value in settings.py which you have to override
https://docs.djangoproject.com/en/3.1/ref/settings/#std:setting-LOGIN_URL

Django backend not returning JSON on production server, getting 404

I have a Django backend that returns json data. I'm able to get data back on my localhost but got a 404 on production server. I'm running nginx in front of gunicorn server. Any ideas why I'm getting a 404? Shouldn't this be able to work to retrieve json data, or do I need to use django rest framework and implement viewsets to make this work?
Not Found
The requested URL /about was not found on this server.
urls.py
urlpatterns = [
url(r'^admin/', admin.site.urls),
url(r'^about', about.get_info),
]
about.py
from django.http import JsonResponse
def get_info(req):
return JsonResponse({"test": "hello"})
The problem is inside url.py. The way the rules are defined currently, it would only allow you to open about/ and admin/, i.e. with the / at the end. To fix this, you can define the URLs as following:
urlpatterns = [
url(r'^admin/$', admin.site.urls),
url(r'^about/$', about.get_info),
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How to ignore or redirect a http request in Django?

I use an Angular 4 frontend and Python Django in the backend.
If I click on the detail button I run the openDetail method in my component
openDetail(id:number){
this.router.navigate(['/motor/detail', {"id": id}])
}
the browser opens the detail component with the URL http://localhost:8000/motor/detail;id=21. Perfect. Important to know is, that I just need the id to work with them in my detail component.
But if I refresh the page I run into a 404 error. --> The current path, motor/detail;id=21, didn't match any of these. Well, this is also clear and jumped into the backend.
main - urls.py
#... some other urls...
url(r'^motor/', include('motorControll.urls')),
motors - urls.py
url(r'^$', views.index, name="index"),
url(r'^overview/$', views.MotorMapping.as_view({'get': 'getAllData'})),
url(r'^detail/$', views.index, name="index"),
url(r'^detail/(?P<id>\d+)/$', views.MotorMapping.as_view({'get': 'getById'})),
url(r'^detail/save/$', views.MotorMapping.as_view({'post': 'save'})),
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I need the id, because the next step, after load the detail page is to load the details by this url http://localhost:8000/motor/detail/21 , it returns JSON with all data.
Your URL mapping in motors.urls is configured properly for the URL /motor/detail/21 -- so it works. But it's not configured for a URL like /motor/detail;id=21.
If you added another route to motors.url so that /motor/detail;id=21 works -- something like url(r'^detail;id=(?P<id>\d+)$', views.MotorMapping.as_view({'get': 'getById'})), then the URL would return raw JSON, so that's NOT what you want.
Instead, the actual solution is more complicated -- you want the URL to be routed to your single page app, and not Django, and have Angular take care of loading the data from Django Rest Framework.

Multiple django apps using same url pattern

I'd like to run two apps with the same url patterns. I would like to avoid having an app-specific slug like domain.com/pages/something-here or domain.com/blog/something-there.
I tried this:
# urls.py
urlpatterns = patterns('',
url(r'^$', 'my.homepage.view'),
url(r'^admin/', include(admin.site.urls)),
url(r'^', include('pages.urls')),
url(r'^', include('blog.urls')),
)
# pages/urls.py
urlpatterns = patterns('',
url(r'^(.+)/$', views.page),
)
# blog/urls.py
urlpatterns = patterns('',
url(r'^(.+)/$', views.post),
)
My code doesn't work, whichever include comes first (here, pages.urls) works ok, other urls (for blog) throw 404.
Thanks in advance
EDIT: I did it like this: created glue.py in the same directory as settings.py. It will handle my homepage and this dispatcher view:
def dispatcher(request, slug):
try:
page = get_object_or_404(Page, slug=slug)
return render(request, 'pages/page.html', {'page': page})
except:
post = get_object_or_404(Post, slug=slug)
return render(request, 'blog/post.html', {'post': post})
I don't know if it's ok. I hope there is a better way.
Thanks for the comments.
I don't know if this is a better answer. But, if these situations are satisfied for you..
if your django app is based on django template rendering.
The url you are talking about, need not be accessed directly by typing the endpoint in the browser itself.
Then, maybe you could consider url namespaces and template redirections.
https://docs.djangoproject.com/en/1.11/topics/http/urls/#url-namespaces
This doesn't work because django urls are resolved in order, meaning that the first url that matches the regexp will be the resolved one. In your case, the the urls included from the blogs application will never be searched, as django already resolved the url on the pages includes line.
Also, the django url module is not supposed to know if a certain page or blog post exists, as i believe in your application this is determined with a database lookup.
The urls module just executes the view that is connected to the first regexp that matches.
You should change your logic, e.g. with perpending "blog/" to blog urls (what's wrong with that?)
url(r'^blog/', include('blog.urls')),
url(r'^', include('pages.urls')),
Notice that the i moved the blog url up, as most generic regxexp should always be the last to be tried by django url resolver.
Alternatively, you could code a proxy view that tries both blog posts and pages. but it doesn't seem the best way to do it to me.
How would you like this to work? They're both using the same URL (which of course is causing problems). How would a user get to a "page" rather than a "blog" or vice versa?
In general, you can't have overlapping URLs in your URL patterns (without including additional data).
EDIT:
So you want the first app to check if it has a view to match the URL and next to take over if the first doesn't? You could do something complicated like writing a "view matcher" to do want you want, but there are much more straigtforward solutions.
The easiest way would be to alter the slug generation function for one of your apps. Have one use some delimeter other than underscores, or always append the name of the app to the slug. This way you could find pages because their url would be "some-slug-page" and blogs would be "some-slug-blog", which you could then write a URL pattern for. If you don't want to add the entire URL, you can append/prepend just the first letter, or whatever you want.
Just think about a way that's acceptable to you to generate URLs for each app which, just by reading the URL, lets you know which app the page belongs to.

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