I'm making a school records webapp. I want staff users to be able to view the user data pages for any pupil by going to the correct url, but without allowing pupils access to each others' pages. However I'm using the same view function for both urls.
I have a working #user_is_staff decorator based on the existence of a user.staff object. Pupil users have a user.pupil object instead. These are discrete, naturally, as no user can have both a .staff and a .pupil entry.
urls.py
(r'^home/(?P<subject>[^/]+)/$', 'myproject.myapp.views.display_pupil')
(r'^admin/user/(?P<user>\d+)/(+P<subject>[^/]+)/$', 'myproject.myapp.views.display_pupil')
views.py
#login_required
def display_pupil(request, subject, pupil=None):
if pupil:
try:
thepupil = get_object_or_404(Pupil, id = pupil, cohort__school = request.user.staff.school)
except Staff.DoesNotExist:
return HttpResponseForbidden()
else:
thepupil = request.user.pupil
thesubject = get_object_or_404(Subject, shortname = subject)
# do lots more stuff here
return render_to_response('pupilpage.html', locals(), context_instance=RequestContext(request))
Doing it this way works, but feels very hacky, particularly as my '#user_is_staff' decorator has a more elegant redirect to a login page than the 403 error here.
What I don't know is how to apply the #user_is_staff decorator to the function only when it has been accessed with the pupil kwarg. There's a lot more code in the real view function, so I don't want to write a second one as that would be severely non-DRY.
Sounds like you want two separate views - one for a specific pupil and one for the current user - and a utility function containing the shared logic.
#login_required:
def display_current_pupil(request, subject):
thepupil = request.user.pupil
return display_pupil_info(request, subject, thepupil)
#user_is_staff
def display_pupil(request, subject, pupil):
thepupil = get_object_or_404(Pupil, id=pupil, cohort__school=request.user.staff.school)
return display_pupil_info(request, subject, thepupil)
def display_pupil_info(request, subject, thepupil):
thesubject = get_object_or_404(Subject, shortname=subject)
# do lots more stuff here
return render_to_response('pupilpage.html', locals(), context_instance=RequestContext(request))
Related
Currently, I have a view that essentially closes a lead, meaning that it simply copies the information from one table (leads) to another (deals), now what I really would like to do is that after clicking close, the user is redirected to another page where the user can update some entries (sales forecast), I have a view that updates the lead, so I thought that I can do something like below:
#login_required
def close_lead(request):
id = request.GET.get('project_id', '')
keys = Leads.objects.select_related().get(project_id=id)
form_dict = {'project_id': keys.project_id,
'agent': keys.agent,
'client': keys.point_of_contact,
'company': keys.company,
'service': keys.services,
'licenses': keys.expected_licenses,
'country_d': keys.country
}
deal_form = NewDealForm(request.POST or None,initial=form_dict)
if request.method == 'POST':
if deal_form.is_valid():
deal_form.save()
obj = Leads.objects.get(project_id=id)
obj.status = "Closed"
obj.save(update_fields=['status'])
## Changing the Forecast Table Entry
forecast = LeadEntry.objects.filter(lead_id=id)
for i in forecast:
m = i
m.stage = "Deal"
m.save(update_fields=['stage'])
messages.success(request, 'You have successfully updated the status from open to Close')
update_forecast(request,id)
else:
messages.error(request, 'Error updating your Form')
return render(request,
"account/close_lead.html",
{'form': deal_form})
This view provides the formset that I want to update after closing the lead
#login_required
def update_forecast(request,lead_id):
# Gets the lead queryset
lead = get_object_or_404(Leads,pk=lead_id)
#Create an inline formset using Leads the parent model and LeadEntry the child model
FormSet = inlineformset_factory(Leads,LeadEntry,form=LeadUpdateForm,extra=0)
if request.method == "POST":
formset = FormSet(request.POST,instance=lead)
if formset.is_valid():
formset.save()
return redirect('forecast_lead_update',lead_id=lead.project_id)
else:
formset = FormSet(instance=lead)
context = {
'formset':formset
}
return render(request,"account/leadentry_update.html",context)
As you can see I’m calling this function update_forecast(request,id) after validating the data in the form, and I would have expected to be somehow redirected to the HTML page specified on that function, however, after clicking submit, the form from the first view is validated but then nothing happens, so I'm the function doesn't render the HTML page
My question how can I leverage existing functions in my views?, obviously, I will imagine that following the DRY principles you can do that in Django, so what am I doing wrong ?, how can I call an existing function within another function in views?
A view returns a response object. In your current code, you're calling a second view but not doing anything with its response. If you just wanted to display static content (not a form that might lead to an action that cares about the current URL) you could return the response object from the second view - return update_forecast(request, id).
But since your second view is displaying a form, you care about what the action for the view from the second form is. The typical Django idiom is to have forms submit to the current page's URL - that wouldn't work if you just call it and return its response object. You could customize the action in the second view, say adding an optional parameter to the view, but the usual idiom for form processing is to redirect to the view you want to show on success. Just as you do in the update_forecast view. Something like this:
messages.success(request, 'You have successfully updated the status from open to Close')
return redirect('update_forecast', lead_id=id)
I want to load a default django page. Nothing fancy. However, the error I get, hints at an id that is incorrectly set.
"Field 'id' expected a number but got 'zoekboek'."
The confusing things here (I am a django beginner, so I wouldn't be surprised if this is not confusing at all for you):
the path for this page in the urls.py is not asking for an id.
the view is not querying anything yet (I found some posts that had similar errors,
but related to a filter).
the debug info points to another view that indeed is requesting an id.
when I add a slash at the beginning of the path, the error is gone!
The code
urls.py
urlpatterns = [
path('', views.scholen, name='scholen'),
path('<school_id>', views.school_detail, name='school_detail'),
path('<school_id>/<groep_id>', views.school_groep, name='school_groep'),
path('<school_id>/<groep_id>/<UserProfile_id>', views.leerling_page, name='leerling_page'),
path('zoekboek', views.zoekboek, name='zoekboek'),
]
views.py
from django.shortcuts import render, redirect, reverse, get_object_or_404
from books.models import Book, Rating
from .models import School, Groep
from profiles.models import UserProfile, Hobby, Sport
from django.contrib.auth.models import User
# Create your views here.
def scholen(request):
"""
Homepage for participating
schools.
"""
scholen = School.objects.all()
context = {
'scholen': scholen,
}
return render(request, 'schools/school_landing.html', context)
def school_detail(request, school_id):
"""
Details of individual schools.
"""
school = get_object_or_404(School, pk=school_id)
groep = Groep.objects.filter(school=school)
context = {
'school': school,
'groep': groep,
}
return render(request, 'schools/school_detail.html', context)
def school_groep(request, school_id, groep_id):
"""
Details of groep.
"""
school = get_object_or_404(School, pk=school_id)
groep = get_object_or_404(Groep, pk=groep_id)
a = groep.naam
kinderen = UserProfile.objects.filter(groep=a)
context = {
'school': school,
'groep': groep,
'kinderen': kinderen,
}
return render(request, 'schools/school_groep.html', context)
def leerling_page(request, school_id, groep_id, UserProfile_id):
"""
Personal page of school kids.
"""
profile = get_object_or_404(UserProfile, pk=UserProfile_id)
# If viewer is owner of page, viewer can edit
owner = False
if request.user == profile.user:
owner = True
context = {
'profile': profile,
'owner': owner,
}
return render(request, 'schools/leerling_page.html', context)
def zoekboek(request):
"""
Page for kids to search their favorite book
"""
context = {
}
return render(request, 'schools/zoek_boek.html', context)
Is this enough information?
Simple fix: move path('zoekboek', views.zoekboek, name='zoekboek'), from the last place to the second place in your urls.
Why?
Because Django URLs are resolved using regular expressions; the docs say here in point 3:
Django runs through each URL pattern, in order, and stops at the first one that matches the requested URL, matching against path_info.
Since your URL path path('<school_id>', views.school_detail, name='school_detail'), is very generic, it matches any string including the string zoekboek; so the request to zoekboek falls into the second line in your URL conf and gets routed to the view school_detail() and a school_id is expected for that view.
Suggestion: to make the URL handling easier and so you can order the URL paths however you like, you could change the URL a bit and add a prefix (for example school/) so that not any string matches the URL paths. For example, this schould work:
urlpatterns = [
path('', ...),
path('school/<school_id>', ...),
path('school/<school_id>/<groep_id>', ...),
path('school/<school_id>/<groep_id>/<UserProfile_id>', ...),
path('zoekboek', ...),
]
There's lots of documentation about Django and the reverse() method. I can't seem to locate my exact problem. Suppose I have two urlconfs like this:
url(r'ParentLists/$', main_page, name = "main_page"),
url(r'ParentLists/(?P<grade_level>.+)/$', foo, name = "foo")
and the two corresponding views like this:
def main_page(request):
if request.method == 'POST':
grade_level = request.POST['grade_picked']
return HttpResponseRedirect(reverse('foo', args = (grade_level,)))
else:
return render(request, 'index.html', context = {'grade_list' : grade_list})
def foo(request, grade_level):
grade_level = request.POST['grade_picked']
parent_list = # get stuff from database
emails = # get stuff from database
return render(request, 'list.html', context = {'grade_list' : grade_list, 'parent_list' : parent_list})
Here, list.html just extends my base template index.html, which contains a drop down box with grade levels. When the user goes to /ParentLists, the main_page view renders index.html with the drop down box as it should.
When the user picks a grade level from the drop down box (say 5th Grade), the template does a form submit, and main_page once again executes - but this time the POST branch runs and the HttpResponseRedirect takes the user to /ParentLists/05. This simply results in an HTML table pertaining to grade 5 being displayed below the drop down box.
The problem is, when the user now selects say 10th Grade, the table updates to show the grade 10 content, but the URL displayed is still /ParentLists/05. I want it to be /ParentLists/10.
Clearly, after the first selection, the main_page view never executes again. Only foo does...and so the HttpResponseRedirect never gets called. How should I reorganize this to get what I'm looking for? Thanks in advance!
As you correctly mentioned you will never redirect to foo() from foo().
So the simple way to fix this is just add similar code as in main_page() view:
def foo(request, grade_level):
if request.method == 'POST':
grade_level = request.POST['grade_picked']
return HttpResponseRedirect(reverse('foo', args = (grade_level,)))
else:
parent_list = # get stuff from database
emails = # get stuff from database
return render(request, 'list.html', context = {'grade_list' : grade_list, 'parent_list' : parent_list})
Please note that I remove grade_level = request.POST['grade_picked'] because as Nagkumar Arkalgud correctly said it is excessively.
Also instead of combination of HttpResponseRedirect and reverse you can use shortcut redirect which probably little easy to code:
from django.shortcuts redirect
...
return redirect('foo', grade_level=grade_level)
I would suggest you to use kwargs instead of args.
The right way to use the view is:
your_url = reverse("<view_name>", kwargs={"<key>": "<value>"})
Ex:
return HttpResponseRedirect(reverse('foo', kwargs={"grade_level": grade_level}))
Also, you are sending "grade_level" to your view foo using the URL and not a POST value. I would remove the line:
grade_level = request.POST['grade_picked']
as you will override the grade_level sent to the method from the url.
New to django. I'm doing my best to implement CRUD using Django, mongodb, and mongoengine. I'm able to query the database and render my page with the correct information from the database. I'm also able to change some document fields using javascript and do an Ajax POST back to the original Django View class with the correct csrf token.
The data payload I'm sending back and forth is a list of each Document Model (VirtualPageModel) serialized to json (each element contains ObjectId string along with the other specific fields from the Model.)
This is where it starts getting murky. In order to update the original document in my View Class post function I do an additional query using the object id and loop through the dictionary items, setting the respective fields each time. I then call save and any new data is pushed to the Mongo collection correctly.
I'm not sure if what I'm doing to update existing documents is correct or in the spirit of django's abstracted database operations. The deeper I get the more I feel like I'm not using some fundamental facility earlier on (provided by either django or mongoengine) and because of this I'm having to make things up further downstream.
The way my code is now I would not be able to create a new document (although that's easy enough to fix). However what I'm really curious about is how I would know when to delete a document which existed in the initial query, but was removed by the user/javascript code? Am I overthinking things and the contents of my POST should contain a list of ObjectIds to delete (sounds like a security risk although this would be an internal tool.)
I was assuming that my View Class might maintain either the original document objects (or simply ObjectIds) it queried and I could do my comparisions off of that set, but I can't seem to get that information to persist (as a class variable in VolumeSplitterView) from its inception to when I received the POST at the end.
I would appreciate if anyone could take a look at my code. It really seems like the "ease of use" facilities of Django start to break when paired with Mongo and/or a sufficiently complex Model schema which needs to be directly available to javascript as opposed to simple Forms.
I was going to use this dev work to become django battle-hardened in order to tackle a future app which will be much more complicated and important. I can hack on this thing all day and make it functional, but what I'm really interested in is anyone's experience in using Django + MongoDB + MongoEngine to implement CRUD on a Database Schema which is not vary Form-centric (think more nested metadata).
Thanks.
model.py: uses mongoengine Field types.
class MongoEncoder(JSONEncoder):
def default(self, o):
if isinstance(o, VirtualPageModel):
data_dict = (o.to_mongo()).to_dict()
if isinstance(data_dict.get('_id'), ObjectId):
data_dict.update({'_id': str(data_dict.get('_id'))})
return data_dict
else:
return JSONEncoder.default(self, o)
class SubTypeModel(EmbeddedDocument):
filename = StringField(max_length=200, required=True)
page_num = IntField(required=True)
class VirtualPageModel(Document):
volume = StringField(max_length=200, required=True)
start_physical_page_num = IntField()
physical_pages = ListField(EmbeddedDocumentField(SubTypeModel),
default=list)
error_msg = ListField(StringField(),
default=list)
def save(self, *args, **kwargs):
print('In save: {}'.format(kwargs))
for k, v in kwargs.items():
if k == 'physical_pages':
self.physical_pages = []
for a_page in v:
tmp_pp = SubTypeModel()
for p_k, p_v in a_page.items():
setattr(tmp_pp, p_k, p_v)
self.physical_pages.append(tmp_pp)
else:
setattr(self, k, v)
return super(VirtualPageModel, self).save(*args, **kwargs)
views.py: My attempt at a view
class VolumeSplitterView(View):
#initial = {'key': 'value'}
template_name = 'click_model/index.html'
vol = None
start = 0
end = 20
def get(self, request, *args, **kwargs):
self.vol = self.kwargs.get('vol', None)
records = self.get_records()
records = records[self.start:self.end]
vp_json_list = []
img_filepaths = []
for vp in records:
vp_json = json.dumps(vp, cls=MongoEncoder)
vp_json_list.append(vp_json)
for pp in vp.physical_pages:
filepath = get_file_path(vp, pp.filename)
img_filepaths.append(filepath)
data_dict = {
'img_filepaths': img_filepaths,
'vp_json_list': vp_json_list
}
return render_to_response(self.template_name,
{'data_dict': data_dict},
RequestContext(request))
def get_records(self):
return VirtualPageModel.objects(volume=self.vol)
def post(self, request, *args, **kwargs):
if request.is_ajax:
vp_dict_list = json.loads(request.POST.get('data', []))
for vp_dict in vp_dict_list:
o_id = vp_dict.pop('_id')
original_doc = VirtualPageModel.objects.get(id=o_id)
try:
original_doc.save(**vp_dict)
except Exception:
print(traceback.format_exc())
I am writing an application in Django, which uses [year]/[month]/[title-text] in the url to identitfy news items. To manage the items I have defined a number of urls, each starting with the above prefix.
urlpatterns = patterns('msite.views',
(r'^(?P<year>[\d]{4})/(?P<month>[\d]{1,2})/(?P<slug>[\w]+)/edit/$', 'edit'),
(r'^(?P<year>[\d]{4})/(?P<month>[\d]{1,2})/(?P<slug>[\w]+)/$', 'show'),
(r'^(?P<year>[\d]{4})/(?P<month>[\d]{1,2})/(?P<slug>[\w]+)/save$', 'save'),
)
I was wondering, if there is a mechanism in Django, which allows me to preprocess a given request to the views edit, show and save. It could parse the parameters e.g. year=2010, month=11, slug='this-is-a-title' and extract a model object out of them.
The benefit would be, that I could define my views as
def show(news_item):
'''does some stuff with the news item, doesn't have to care
about how to extract the item from request data'''
...
instead of
def show(year, month, slug):
'''extract the model instance manually inside this method'''
...
What is the Django way of solving this?
Or in a more generic way, is there some mechanism to implement request filters / preprocessors such as in JavaEE and Ruby on Rails?
You need date based generic views and create/update/delete generic views maybe?
One way of doing this is to write a custom decorator. I tested this in one of my projects and it worked.
First, a custom decorator. This one will have to accept other arguments beside the function, so we declare another decorator to make it so.
decorator_with_arguments = lambda decorator: lambda * args, **kwargs: lambda func: decorator(func, *args, **kwargs)
Now the actual decorator:
#decorator_with_arguments
def parse_args_and_create_instance(function, klass, attr_names):
def _function(request, *args, **kwargs):
model_attributes_and_values = dict()
for name in attr_names:
value = kwargs.get(name, None)
if value: model_attributes_and_values[name] = value
model_instance = klass.objects.get(**model_attributes_and_values)
return function(model_instance)
return _function
This decorator expects two additional arguments besides the function it is decorating. These are respectively the model class for which the instance is to be prepared and injected and the names of the attributes to be used to prepare the instance. In this case the decorator uses the attributes to get the instance from the database.
And now, a "generic" view making use of a show function.
def show(model_instance):
return HttpResponse(model_instance.some_attribute)
show_order = parse_args_and_create_instance(Order, ['order_id'])(show)
And another:
show_customer = parse_args_and_create_instance(Customer, ['id'])(show)
In order for this to work the URL configuration parameters must contain the same key words as the attributes. Of course you can customize this by tweaking the decorator.
# urls.py
...
url(r'^order/(?P<order_id>\d+)/$', 'show_order', {}, name = 'show_order'),
url(r'^customer/(?P<id>\d+)/$', 'show_customer', {}, name = 'show_customer'),
...
Update
As #rebus correctly pointed out you also need to investigate Django's generic views.
Django is python after all, so you can easily do this:
def get_item(*args, **kwargs):
year = kwargs['year']
month = kwargs['month']
slug = kwargs['slug']
# return item based on year, month, slug...
def show(request, *args, **kwargs):
item = get_item(request, *args, **kwargs)
# rest of your logic using item
# return HttpResponse...