How to realtime highlighting - django

Does anybody know how can I make real-time highlighting in forms in Django?
Here's what I'm doing: I have a model, and a few instances of it. I'm serializing the selected object to json and sending it to my form (e.g. textarea). Then I can edit it, deserialize, and send it back to the db. Are there any options for highligting this json text in real time?

Related

How to Fill Form with Data in DJango without Update

New to Django here. I have a link to a form in DJango. I use the CreateView to have the user enter the initial information. It all works great and the data is accurately saved to the database. My issue is this: I would like that same link to open the form (it's a one-to-one relationship) with the filled data so the user can see what they have previously entered and correct, edit or update as needed. The form currfently opens as a blank form so if the user has entered that information previously they are unable to see it. I cave researched get_or_create and update_or_create as well as a number of other topics, but can't seem to figure this out. This needs to be a user-friendly experience so multiple entires or clicking multiple buttons to access the data is not an option. How best can I implement this?
#Don you can checkout django formsets, I think this will help in this situation. And you can use a single FormView for all your needs by overriding its methods.
Have you looked at Django Sessions. It’s a simple way of saving session data and passing the data to future requests. https://docs.djangoproject.com/en/3.0/topics/http/sessions/. I. In your form view you cloud save the session data you want to pass to your next form. In your next form, you could use the session data as default values. I’ve done something similar in the past.

Improving the loading performance of foreignkey fields with thousands of options

I have a similar situation as this post in which I encounter a slow page loading as I have thousands of entries in a foreignkey field.
At modelform, is there a way to improve the page loading while keeping the dropdown function? I have used select2 to efficiently find the chosen item in the dropdown, thus want to keep this function.
Django has to fetch all those foreignkey objects from database and then render them as HTML. This is why it takes a lot of time. Fetching from database can be pretty quick if you cache everything, but rendering to HTML will still be a problem.
Here's a solution that I think would work best:
Exclude that ForeignKey field from your form.
Instead, just create a blank input field. You'll have to capture user's input via JavaScript and send that value to your backed to fetch suggestions. In fact, select2 supports fetching data from backend via AJAX, So, half of your work is done.
Create a view which will take that AJAX request and search the database for suggestions and send them back to the client.
And you're done.

How to parse XML feed and create Django objects from it

is there a good package to parse XML/JSON data and map it to Django model's object fields? The ideal solution would be the one that supports object updates. What can you recommend?
UPDATE:
Will tell a bit about my requirements. There affiliate programs that supply partners with content via XML feeds. What I need is to parse the feed time from time and get content out of it and update already existing content (objects).

Hidden select multiple items Django

I've got several forms in my django app that require support for attachments. Each form instance may have any number of attachments, including none. I want to present a jQuery based upload widget for managing these uploads, allowing the uploads to be processed asynchronously. The attachments are stored in their own model, so there is then a many-to-many from the attachments model to each model that requires attachments. When an attachment is sucessfully uploaded and processed, the view handling the upload will return the id in the attachments model, which will then be inserted into a hidden field on the form. I'm currently trying to decide how best to represent this in the form.
One method would be to simply have a single hidden input which takes a comma separated list of ids. This would then require quite a lot of manual processing and validation on submission, which I can't help feeling could be avoided.
Elsewhere, I've used a HiddenInput for a single value where I'm doing something similar and dynamically adding items to the related model in the form. I can't however see how I can extend this directly to a Many to Many from a simple Foreign Key.
Anyone able to suggest the best way to go about doing this?
Try to use formsets or model_formsets to create a form for creating/editing multiple objects, also you can use javascript to add forms dynamically in your browser.

Plone-like search box in Django?

Plone has a beautiful search box with a "Google suggest" like functionality for its site. It even indexes uploaded documents like PDFs. Does anyone know of a module that can provide this kind of functionality in a Django site?
Plone implements it's LiveSearch feature by maintaining a separate metadata table of indexed attributes (fields such as last modified, creator, title are copied from the content objects into this table). Content objects then send ObjectAdded/ObjectModified/ObjectRemoved events, and an event subscriber listens for these events and is responsible for updating the metadata table (in Django events are named signals). Then there is a Browser View exposed at a fixed URL that searches the metadata and returns the appropriate LiveSearch HTML, and finally each HTML page is sent the appropriate JavaScript to handle the autocomplete AJAX functionality to query this view and slot the resulting HTML results into the DOM.
If you want your LiveSearch to query multiple Models/Content Types, you are likely going to need to send your own events and have a subscriber handle them appropriately. This isn't necessary for a smaller data sets or lower traffic sites, where the performance penalty for doing multiple queries for a single search isn't a concern (or you only want to search a single content type) and you can just do several queries from your View.
As for the JavaScript side, you can roll-your-own or use an existing JavaScript library. This is usually called autocomplete in the JS library. There is YUI autocomplete and Scriptaculous autocomplete for starters, and likely lots more JavaScript autocomplete implementations out there. Plone uses KSS for it's JavaScript library, the KSS livesearch plugin is a good place to start if looking for example code to pluck from.
http://pypi.python.org/pypi/kss.plugin.livesearch
And a tutorial on using KSS with Django:
http://kssproject.org/docs/tutorial/kss-in-django-with-kss-django-application
KSS is quite nice since it cleanly separates behaviour from content on the client side (without needing to write JavaScript), but Scriptaculous is conceptually a little simpler and has somewhat better documentation (http://github.com/madrobby/scriptaculous/wikis/ajax-autocompleter).