I have written what I hope to be a re-usable Django app, but I have a bit of a conundrum on how to make the post form handling flexible. The simplified version of my view code looks like:
def do_form(request, entity_id, template_name, success_url):
form = MyForm(request.POST or None)
if request.method =='POST':
if form.is_valid():
#do some business logic
return HttpResponseRedirect(finished_url)
return render_to_response(template_name,
{'form': form},
context_instance=RequestContext(request))
I have followed the advice in James Bennets book "Practical Django Projects" and so you can now configure the template and the success url in the url conf, so for example my url conf could look like this:
urlpatterns = patterns('myapp.views',
url(r'^do/(?P<entity_id>\d+)/$',
view = 'do_form',
name = 'do_form_view',
kwargs={'template_name':'form.html',
'success_url':'/finish/'},),
url(r'^finish/$',
view = 'finish',
name = 'finish_view')
)
This is all very well and good but when I have come to use this in my real world application I find myself in a situation that this form sits in the middle of some workflow, and I want the success url to be something like /continue/<workflow_id>/ , and the problem is that you can only have a hardcoded url in the url conf, and the workflow_id will vary every time I hit the do_form code.
Can any one suggest a way to get around this?
You can achieve that by changing the following..
in do_form() in views.py
change the return HttpResponseRedirect to
return HttpResponseRedirect('/continue/%s' %(workflowid))
And in urls.py, you can have
url(r'^continue/(?P<workflowid>\d+)/$',
view = 'continue',
name = 'continue_view')
and for the continue() view in views.py
def continue(request, workflowid=None):
...
This way.. whenever you access the url /continue/ without a number, workflowid will be equal to None. Every other time when you do have a workflowid attached for e.g. like /continue/23/ , then inside your continue() view you can access that id through the variable workflowid.
When you pass a hypothethical "flexible" success_url to a view, that view MUST supply the desired identifier. So if you mismatch the URL and the view, we can't avoid having a "breach of contract" between the two.
Therefore if we are to have flexible URLs, some kind of contract shall have to be enforced, and there will be no loss of generality if we do this through a special syntax for URLs:
'finished_url': '/finish/<workflow_id>/'
Then, of course, the view shall have to instantiate the variable through a string replacement to honor its side of the contract: instead of
return HttpResponseRedirect(finished_url)
you will have
return HttpResponseRedirect(finished_url.replace('<workflow_id>', WorkflowID))
This should keep things reasonably simple.
When reusing code, you will have to keep in mind that <workflow_id> is whatever that app uses to call workflow id, and that's why I use a complicated string such as workflow_id instead of id or maybe $1.
EDIT: I was going to add the code for the next step (intercepting workflow ID in argument of finish), but I see that keithxm23 beat me to the punch :-)
You can do it the same way people have been "overriding" Django's function-based generic views for years: simply wrap the view in another view:
def custom_do_form(request, entity_id, template_name, success_url):
template_name = some_method_to_get_template()
return do_form(request, entity_id, template_name, success_url)
Related
def resume_edit(request, r_id):
r = Resume.get.object(pk=r_id)
resume = ResumeModelForm(instance=r)
resume.fields['email'].widget.attrs['readonly'] = True
return render(request, 'resumes/resume.html', context)
I tried to do this but its not working, i know how to do it in Forms.py , but i want to know in views its possible or not?
Im using Django 2.0
Yes, since django-1.9, a field has a .disabled attribute that can be set to True:
So we can use:
def resume_edit(request, r_id):
r = Resume.get.object(pk=r_id)
resume = ResumeModelForm(instance=r)
resume.fields['email'].disabled = True
return render(request, 'resumes/resume.html', context)
This will not only ensure that the HTML of the corresponding form parts is disabled, but will also ignore possible changes when you post the Form (note that you of course first need to disable the field).
Since the render(..) call produces the HTML, the field should of course be altered before it is rendered, validated, or .save()'d.
The .disabled attribute is typically better than using readonly, etc. Since some form elements have a special way to disable the element at the HTML level (some use disabled instead). Furthermore like said before it does not only disable the form element at the HTML level. If a user wants to post malicuous values, then the form will simply ignore these.
My views.py code:
from django.template import Context, loader, RequestContext
from django.http import HttpResponse
from skey import find_root_tags, count, sorting_list
from search.models import Keywords
def front_page(request):
if request.method == 'get' :
str1 = request.getvalue['word']
fo = open("xml.txt","r")
for i in range(count.__len__()):
file = fo.readline()
file = file.rstrip('\n')
find_root_tags(file,str1,i)
list.append((file,count[i]))
sorting_list(list)
for name, count in list:
s = Keywords(file_name=name,frequency_count=count)
s.save()
fo.close()
return HttpResponseRedirect('/results/')
else :
str1 = ''
list = []
template = loader.get_template('search/front_page.html')
c = RequestContext(request)
response = template.render(c)
return HttpResponse(response)
def results(request):
list1 = Keywords.objects.all()
t = loader.get_template('search/results.html')
c = Context({'list1':list1,
})
return HttpResponse(t.render(c))
#this for everyone.
the flow is this:
1) I run my app on the server .
2)It shows me the search page due to the else part of the view "def front_page(request)", now I want to execute the if part of the view "def front_page(request)" because I want to execute my python code written there and the redirected to the view "def results(request)", how can I do that ?
3) what should I mention in "action" of the front_page.html and in urls.py so that I can get back to the same view again. because I could'nt get back to the same view that I want it is repetitively showing me the same search page.Please help.
To enlarge upon the answer posted by #Barnaby....by using action='#' your form will be posted to the same url as the url used in the get request for the form.
Then in your view code, you have logic that says - if the request for this url is a GET request then do the work to configure the form, otherwise, you assume it is a POST and then you can handle the response.
Additionally I would advise that the your view explicitly checks that the request is a POST and if not make the assumption that it is a GET, rather than the other way around (as you have it), this is safer, as GET and POST are not the only request types, and you definitely need to know that you are dealing with a POST request if you want to deal with variables submitted in the POST request.
Hope that helps
Short answer: action="#". This is a HTML trick to post back to the current URL.
The general answer to how to reference a view in a template is to use the url tag. You may also want to consider using Django's forms functionality.
I need some guidance on best practice implementation of the following.
I have a scenario where I am building an app, but if it matches a certain "category" or "locale" and want to redirect it to a page in between else just go the normal route.
Here is my simple views.py
if form.is_valid():
...
kwargs = {'project_id':project_id, 'categories':request.POST['categories'], 'locale':request.POST['locale']}
process_se(request, **kwargs)
return HttpResponseRedirect(obj.next_url)
Here is what I have in my models.py file but it seems to be very inconsistent.
Is there a better way to handle this request?
def process_se(self, request, **kwargs):
if "All" or "Sweden" in kwargs['locale']:
if "Technology" or "Internet" in kwargs['categories']:
next_url = request.build_absolute_uri(reverse('project_new_se', kwargs={'project_id': self.id}))
else:
next_url = request.build_absolute_uri(reverse('project_new_step2', kwargs={'project_id': self.id}))
self.next_url = next_url
UPDATES:
I am using forms.ModelForm, categories and locales are ManyToManyField's
I have simulated a for in the shell and still seem to get no result
Here is the cleaned_data output
f.cleaned_data
{'locale': [<Locale: Sweden>, <Locale: All>], 'categories': [<Category: Technology>, <Category: Internet>]}
Although running this for fields in the form seem to render perfectly fine based on your solution
I originally proposed putting this code in the form class, but ApPeL revised the question to point out that locale and categories are many-to-many fields on the model. So now I suggest putting a method like this in your model:
def requires_swedish_setup(self):
"""
Return True if this project requires extra Swedish setup.
"""
return (self.locale.filter(name__in = ('All', 'Sweden')).exists())
and self.categories.filter(name__in = ('Technology', 'Internet')).exists())
and then implementing your view like this:
if form.is_valid():
project = form.save()
next = 'project_new_step2'
if project.requires_swedish_setup():
next = 'project_new_se'
next_url = reverse(next, kwargs={'project_id': project.id})
return HttpResponseRedirect(next_url)
Some notes:
I'm assuming that Locale and Category objects have name fields (if not, use whatever field contains the name you are testing).
It's not a good idea to read form data out of request.POST (widgets haven't had a chance to run, and it hasn't been validated): it's better to use form.cleaned_data.
You don't need to call request.build_absolute_uri in this case: it's fine to feed the result of reverse directly to HttpResponseRedirect.
"All" or "Sweden" in kwargs['locale'] is probably not what you mean: it parses like "All" or ("Sweden" in kwargs['locale']) and so is always true.
I have the following middleware class:
class CommonContextMiddleware:
def process_template_response(self, request, response):
# Get the context and top videos
context = response.context_data
...
# Add most_recent and most_viewed to the context...
context['most_recent'] = top_videos['most_recent'][:3]
context['most_viewed'] = top_videos['most_viewed'][:3]
# ...then continue rendering
return response
However, no matter what I put in the function, it's never being called. I presumed that this method would be called for every single template response generated, am I wrong?
Thanks in advance.
I assume when you're talking about "template response", you are actually returning a TemplateResponse from your Django view?
This isn't really the best place for this sort of thing. If you just want to add variables into every template context, the best place to do it is in a context processor.
Using Marius Gedminas's excellent blog post, I have created a custom traverser for a folder in my site.
This allows me to show: http://foo.com/folder/random_id
Instead of: http://foo.com/folder/object.html?id=random_id
The configuration side works great, I can catch the random_ids and search through my messages for the correct one, ready to display.
My problem is that I'm unsure how to then display the data via my usual page templates - at the TODO point in his original code ;)
if name == 'mycalendar':
mycalendar = ... # TODO: do something to get the appropriate object
return mycalendar
Usually I'd use something similar to:
class Test(BrowserPage):
template = ViewPageTemplateFile('atest.pt')
def __call__(self):
return self.template()
But I can't work out how to do this correctly in the context of the custom traversal.
UPDATE: To be clear I want to avoid adding anything else to the url (No: http://foo.com/folder/random_id/read).
I don't need the view to be available via any other address (No: http://foo.com/folder/read)
The ZCML for the view I'd like to use is:
<browser:page
for="foo.interfaces.IFooFolderContainer"
name="read"
template="read.pt"
permission="zope.ManageContent"
/>
I'm guessing (on further advice), something along the lines of:
return getMultiAdapter((mycalendar, self.request), IPageTemplate, name=u'read')
Or even a default view for the object type (a dict in this case) that's being returned:
<browser:page
for="dict"
name="read"
template="read.pt"
permission="zope.ManageContent"
/>
It would be easier to answer your question if you showed what your custom traverser is doing.
Essentially, you want something like this:
def publishTraverse(self, request, name):
if name in self.context:
return MyMessageView(self.context[name], request)
# fall back to views such as index.html
view = queryMultiAdapter((self.context, request), name=name)
if view is not None:
return view
# give up and return a 404 Not Found error page
raise NotFound(self.context, name, request)
where MyMessageView can be something as simple as
class MyMessageView(BrowserPage):
__call__ = ViewPageTemplateFile('read.pt')
Disclaimer: I'm not sure if the view you instantiate directly will be protected by a security wrapper; make sure your functional tests ensure anonymous users can't view messages if that's what you want.
If you end up at a proper object with your custom traverser, you can just tack on the template name and user "context" in that template. So http://foo.com/folder/random_id/my_template and in the template do the normal <h1 tal:content="context/title" /> stuff.
IIUC, what you want is to render the 'read' view when somebody requests /folder/random_id. If that's the case, all you need to do is make your traversal return an object (IFolderContent, maybe) representing a random_id and specify the 'view' page as the defaultView for IFolderContent.
The defaultView is needed because there's no view specified for the random_id object in your URL.