Here's the view that updates the timestamp of a model in database whenever it's called,
def data(request):
new = Data.objects.filter(user=request.user)
new.update(timestamp=timezone.now())
return HttpResponse('')
This view is related to this URL,
url(r'^go/$', views.data, name='data')
Everything is fine, but how can I call this view & update the database without refreshing the page?
This is a great question as its something that may not seem as logical in django as say node or js based server and client interactions. Let me give a generic response then go more detailed.
Django is a web server. It has some newer functionality that allows it to more easily interact with javascript than it could in the past, but it is normally used in conjunction with a javascript framework. I'll normally build a django app w/ django-rest-framework and reactjs. So my workflow is normally to build the datamodel, serve up the page with compiled js as a static asset, and have those two communicate via a rest-api stood up with DRF.
Specifically to your question, you can simply have your django model communicate with the server via ajax posting to endpoint in your app. An example of a jquery/ajax post is available at this link. The only other thing you will want to look into is supporting csrf which Django discusses in the docs.
Let me know if this helps. If it does but requires specific snippets, let me know.
Related
I want to write an API, i.e. hosted at www.api.mywebsite.com (not affiliated with Shopify) and then have a shopify blog post that queries that API and displays that data using javascript.
I know how to do the API potion, but can I and if so how do I do the second part where I use JS to query and display data?
Simple! Add an App Proxy to your App. With that, you setup an end point to call in your App. On the blog page you can send an Ajax GET with an ID to your App, which can then get dynamic content ready for you to use. You can either format the response as Liquid or as JSON as two examples. Send back Liquid, and Shopify renders it for you. Send back JSON and you can stamp out your data in a template.
And best of all it is a secure callback to your App that you know came from Shopify, so you have no hassles or security problems. Look in your App for Extensions, and enable Online Store, where you can tinker with the Proxy.
I'm using https://github.com/sahat/hackathon-starter/tree/es6 which leverages Jade in an ExpressJS & MongoDB NodeJS environment. My questions is how can I update #{event.location} && #{event.city} in Front-end if they change inside MongoDB in the back-end?
I do not want to refresh the entire website in order for #{event.location} and #{event.city} to be updated in the front-end.
Could someone please explain how to do this or if there is a better way of achieving this? Maybe with Socket.IO or some other way. I'm fairly new to Node, JS, Jade etc and can't even grasp a decent way of refreshing part of the page with JADE....
Thank you in advance for your help ! Kudos
Express/Jade can only render the page once from backend when the HTTP request comes.
If you have to update the data on frontend, you will have to use different strategy depending on how your data is updated.
If your data in the backend is updated via the same frontend or at known time you can use AJAX calls to server and fetch the values intermittently.
If data is updated via a different channel then socket.io would be the way to go. You can emit events from the backend on data change and receive the events on frontend app and update the data fields only using javascript bindings.
If you have too many manipulations of data to be done I would suggest using a frontend framework from the likes of Angular or Meteor.
I have a php program/app which asks for input, generate an image and post th image link to user's timeline (processor.php). I used PHP SDK in posting to timeline since I am more familiar with PHP. Now, in my gallery.php, i want to show like buttons for each generated image. I am aware that i have no option but use JS SDK in making button. but is it fine if i use two different SDK's in a single app?
processor.php - PHP SDK
gallerry.php - JS SDK
thanks for your answer! I would love to try your suggetions too
There shouldn't be any problem using PHP and JS in the same application, quite a common use case. You would normally use PHP to create the Web Application structure, handle backend logic, and then use JS to handle UI events.
There's nothing special about combining the two, just create the Web page with JS as normal for the view, and use PHP to build it.
Hope this helps.
Yes, there is no problem, the two APIs are designed to work together. The PHP API is usually used to created the backend logic (for example OAuth implementation, posting and getting data, etc) and the JS API to handle user iniated events.
Also see this: https://stackoverflow.com/a/6728092/1107118 on how to handle login state. Normally the JS API is used for logging in too, and then with the PHP API you take the access token and do the backend actions.
I'm using TastyPie and Django to build out my backend for an application that will have browser and mobile (native iOS) clients.
I have been through the TastyPie and Django docs, can authenticate successfully either using the TastyPie resources I set up, or using Djangos built in views. I see a lot of examples on including the CSRF token on the page and grabbing it with your JavaScript, and that works, but I don't understand now to actually determine whether a user is logged in on initial page load (from JavaScript).
Example:
If I want to serve static HTML from a separate, fast web server, and cache my application JavaScript, and only interact with Django through TastyPie views, how do I determine if the user is logged in (and know to render a login form or the app views using JavaScript), and after logout, is there any session information I need to remove from the client browser?
If I were to serve up HTML through Django's template engine, I could render the login form through there appropriately, but that seems not ideal if I want to truly decouple my JavaScript app from Django (and behave like a mobile client).
Edit: I am using Backbone.js, but I don't think that should matter.
UPDATE:
I think I figured it out reading through Django's CSRF documentation again.
If your view is not rendering a template containing the csrf_token template tag, Django might not set the CSRF token cookie. This is common in cases where forms are dynamically added to the page. To address this case, Django provides a view decorator which forces setting of the cookie: ensure_csrf_cookie().
If I do not want to render Django templates, this reads like I can still use the cookie and pull that into my Backbone or jQuery AJAX methods. I'm not sure if TastyPie ensures the cookie will be sent or how to tie into it.
If I use AJAX to logout, will the cookie automatically be removed or does it become invalid? Are these CSRF tokens unique to each user session? I'll have to test some things tomorrow with it. Is it possible to use Django decorators on TastyPie views?
A mobile client doesn't care if the Javascript comes from Django or any other web server. So go ahead and put all your JavaScript and static HTML on another server.
If you want your mobile app to see if the user is logged in, it should make an AJAX call to your Django backend (where the request is authenticated). The data returned should indicate if the session is active (user is logged in).
Another AJAX call can perform the Django logout function.
I am new in restful programing. I have a django website, my goal is to load part of the website asynchronously.
By default what I do now is:
call a url (e.g. localhost:8080/index) -> Routes the Django view -> View takes data from database (mongodb if you are curious) -> View gets the template -> Render all together and send back to browser
What I want to improve is:
When I have opened a url e.g. localhost:8080/index and I trigger an event (e.g. click a <a>) to send a request to my database and load other data.
My question:
What is the step I have to do to bridge the javascript / ajax with my mongodb safely?
Additionally I am considering to use a front end MCV framework (I think about backbone/I have limited knowledge as well) to handle the front-end requests. E.g. localhost:8080/index#2 returns objects with id : 2 of my database.
You should look at the following rest API frameworks for django. They will help save you a lot of time.
Django Tastypie
Django Rest Framework
I have used both and personally like tastypie better. Once you have integrated one of these in your project you can use any front end javascript framework like angularjs or backbone or even not use one and simply make a call to the resource url to get the data via ajax.