Sorry if this is a noob question I am still learning. I have passed a variable from python code to a jinja2 HTML template to set up a URL, like this:
Delete
When this link is pressed it should run a query that deletes the entity with that ID. But when the link is pressed it goes to /delete/1827424298 for example, which results in a 404 error as the request handler doesn't exist.
I need to pass that ID back into my python code so it can run a method to delete the entity with that same ID. How do I go about doing this? Using webapp2 if that is important.
class DeleteRequestHandler(webapp2.RequestHandler):
def get():
template = template_env.get_template('myrequests.html')
context = {
'results': results.key.id()
}
self.response.out.write(template.render(context))
EDIT: I've added my delete handler - it is incomplete as I have yet to add the query to delete the entity. My thinking behind it so far is I can grab the results.key.id() from the jinja2 template and put it into results but I am not sure if this would work.
So I think what you're confused about is how to set up a route handler with a dynamic part to the URL. It's a shame that this is completely skipped over in the webapp2 tutorial, as it's a fundamental part of writing any web application. However, it is covered well in the guide to routing, which you should read.
At its simplest, it's just a matter of putting a regex in the route:
app = webapp2.WSGIApplication([
...
(r'/delete/(\d+)', MyDeleteHandler),
])
which will now route any URL of the form /delete/<number>/ to your deletion handler.
The ID that you pass in the URL will be the first positional argument to the handler method:
class MyDeleteHandler:
def get(self, item_id):
key = ndb.Key(MyModel, item_id) # or whatever
Related
I want to write custom template loader for my Django app which looks for a specific folder based on a key that is part of the request.
Let me get into more details to be clear. Assume that I will be getting a key on every request(which I populate using a middleware).
Example: request.key could be 'india' or 'usa' or 'uk'.
I want my template loader to look for the template "templates/<key>/<template.html>". So when I say {% include "home.html" %}, I want the template loader to load "templates/india/home.html" or "templates/usa/home.html" or "templates/uk/home.html" based on the request.
Is there a way to pass the request object to a custom template loader?
I've been searching for the same solution and, after a couple days of searching, decided to use threading.local(). Simply make the request object global for the duration of the HTTP request processing! Commence rotten tomato throwing from the gallery.
Let me explain:
As of Django 1.8 (according to the development version docs) the "dirs" argument for all template finding functions will be deprecated. (ref)
This means that there are no arguments passed into a custom template loader other than the template name being requested and the list of template directories. If you want to access paramters in the request URL (or even the session information) you'll have to "reach out" into some other storage mechanism.
import threading
_local = threading.local()
class CustomMiddleware:
def process_request(self, request):
_local.request = request
def load_template_source(template_name, template_dirs=None):
if _local.request:
# Get the request URL and work your magic here!
pass
In my case it wasn't the request object (directly) I was after but rather what site (I'm developing a SaaS solution) the template should be rendered for.
To find the template to render Django uses the get_template method which only gets the template_name and optional dirs argument. So you cannot really pass the request there.
However, if you customize your render_to_response function to pass along a dirs argument you should be able to do it.
For example (assuming you are using a RequestContext as most people would):
from django import shortcuts
from django.conf import settings
def render_to_response(template_name, dictionary=None, context_instance=None, content_type=None, dirs):
assert context_instance, 'This method requires a `RequestContext` instance to function'
if not dirs:
dirs = []
dirs.append(os.path.join(settings.BASE_TEMPLATE_DIR, context_instance['request'].key)
return shortcuts.render_to_response(template_name, dictionary, context_instance, content_type, dirs)
While using the Routes library I want to redirect certain URLs. The documentation says it can be achieved like this:
map.redirect("/legacyapp/archives/{url:.*}", "/archives/{url}")
And I am indeed able to redirect to a URL this way. However I am unable to map/parse the URL arguments from the request to the redirect. My code looks like this:
app.mapper.redirect( "/repository/status_for_installed_repository{url:.*}", "/api/repositories/check_updates/{url}" )
and if the app is passed this:
curl -L 'FQDN/repository/status_for_installed_repository?owner=qqqqqq&changeset_revision=e5f6ced3e91f&name=asdsadsadas'
it redirects me to
GET /api/repositories/check_updates
but I cannot find a way how to obtain the values of owner name and changeset_revision.
I expect this to be a common use case as generally you do not want to lose arguments when redirecting?
Any help is much appreciated. Thanks.
I ended up implementing it as follows:
def _map_redirects( app ):
"""
Add redirect to the Routes mapper and forward the received query string.
Subsequently when the redirect is triggered in Routes middleware the request
will not even reach the webapp.
"""
def forward_qs(environ, result):
qs_dict = urlparse.parse_qs(environ['QUERY_STRING'])
for qs in qs_dict:
result[ qs ] = qs_dict[ qs ]
return True
app.mapper.redirect( "/repository/status_for_installed_repository", "/api/repositories/check_updates/", _redirect_code="301 Moved Permanently", conditions=dict( function=forward_qs ) )
return app
I'm writing a web app which has a page for admin tasks. One of the tasks is that the admin users must be able to edit other users details. Alas, I've fallen at quite a simple roadblock.
I've set up a very simple jQuery AJAX Get request, successfully transferring a string to the server and back. This is just background, but not the issue. The issue lies in retrieving other user's objects.
At the moment, with a username I know exists, this code which is accessed in views.py, produces a 500 Internal Server Error.
#login_required
def user_edit_getuser(request):
# Like before, get the request's context.
context = RequestContext(request)
inputname = request.GET['inputNameSend']
user_obj = User.objects.get(inputname)
return HttpResponse(inputname) #later will return a JSON String
get takes keyword arguments only: the key is the field to look up.
user_obj = User.objects.get(username=inputname)
Also, you should probably deal with the possibility that the GET request has no inputNameSend key.
For JS development, you can usually see the error page in the Chrome dev tools/Firebug console in the Network tab.
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.