Well, I'm designing a web application using Django. The application allow users to select a photo from the computer system and keep populating onto the users timeline. The timeline view have a list/grid of all the photos which the user has uploaded sorted chronologically, showing 50 photos and then a pull to refresh to fetch the next 50 photos on the timeline.The implementation works for multiple users.
Now for fast user experience of the app I'm considering caching. Like most sites store the timeline of the user onto cache so that whenever the user logs in it the first place to check for information the request is served out of the cache and if it is not available there then you go to the DB to query for the information.
Primarily in one line I'm trying to cache all the timelines for different users in cache for now.
I'm done with building of the webapp minus the cache part. So , my question is how do I cache all the timelines of different users??
There is a big difference between public caching and the caching of private data. I feel your data is private and thus needs a different strategy. There is a nice overview of the different ways to implement testing and, more importantly, the different things you need to take into account: The Server Side (Tom Eastman). This has a part on speed and caching (16:20 onward). It explains how to use etag and last_modified headers with django.
I have a log in to my site using Twitter. It all works great.
Whilst I can do a call to get the current users details etc and log them in, I'm a bit stumped on how I make calls to get the profile images of users stored in my database; those who may not be using the website at that time?
I am using the monkehTweets Twitter library:
https://github.com/coldfumonkeh/monkehTweets
To get the current user, I sign them in and do this:
application.objMonkehTweet.setFinalAccessDetails(
oauthToken = returnData.token,
oauthTokenSecret = returnData.token_secret,
userAccountName = returnData.screen_name
);
local.userDetails = application.objMonkehTweet.getUserDetails(user_id=returnData.user_id);
As part of the log in process on my website, if a user hasn't used the site before, I store their Twitter ID.
I was hoping to then use this to display their profile images on the posts they make to other users.
What is the best approach to achieve this? With the Facebook API, you can make requests to a URL with the ID...but Twitter doesn't seem to allow this.
I would prefer not to 'store' the image on my own file system. This was a possibility I had in mind, but I'd rather use the API to always ensure the latest data.
Is there a way to use my own app details through OAuth to access this?
Any help would be greatly appreciated.
Thanks,
Michael.
PS - I am using ColdFusion (Railo) to do my server-side based authentication.
The twitter api returns profiles with the images (if you are looking it up) in the key profile_image_url
So you could store them in a cache like:
if(!cacheKeyExists(twitterID)){
// Code to get a twitter profile through monkehtweet
cachePut(twitterID, profile.profile_image_url);
}
return cacheGet(twitterID);
Hope this helps
I've recently started using Pushover.net, I've done some searching and can't find any examples of it being integrated with a django project.
Since i can't find any examples I've decided it would be fun to try myself. What I'm interested in is how you would suggest I do it. I want the actual pushover part as decoupled a possible, hence doing it asas an app.
What I'm not entirely sure on how to approach is the user authorization. The idea being a user enters their pushover user key and its saved in a user profile model using django's AUTH_PROFILE_MODULE with some functions such as has_pushover but obviously I'd like some security so the user keys aren't stored in plaintext. What do people suggest for this?
Is there some inbuilt django security I can use?
In the past when I've needed to encrypt Django fields I used the encrypted fields available in django-fields. You could use one of these on your UserProfile model and define a has_pushover() method on the model which basically returns whether the pushover token field is None or not.
I'm guessing because you're talking about storing each user's Pushover token you are wanting to build an app for pushing arbitrary notifications to your website's users? This is in contrast to having the website just push notifications to yourself for site events.
I have a website built in Django. One feature of this website is booking hotels. Now, my client has many agents who have websites. We want to give the facility of booking on these websites. So, I am thinking to use iframe on these websites( with the consent of the respective agent owners), which will point to the booking page of our website. Once booking is done, we will return success message and email the user. IS this a viable solution? Or, are there any other options?
thanks
One way of doing this it's creating a rest api using a helper that works with django like django-piston so your agents could work with them to perform booking.
Should be easy to add a form to any agents site with this way. Or even using ajax if the uri returns a json.
Iframes is not the way you should go I think... I also think that you need to define the API on your website and then you just do requests from the client website to your backend.
You're building a web application. You need to store the state for a shopping cart like object during a user's session.
Some notes:
This is not exactly a shopping cart, but more like an itinerary that the user is building... but we'll use the word cart for now b/c ppl relate to it.
You do not care about "abandoned" carts
Once a cart is completed we will persist it to some server-side data store for later retrieval.
Where do you store that stateful object? And how?
server (session, db, etc?)
client (cookie key-vals, cookie JSON object, hidden form-field, etc?)
other...
Update: It was suggested that I list the platform we're targeting - tho I'm not sure its totally necessary... but lets say the front-end is built w/ASP.NET MVC.
It's been my experience with the Commerce Starter Kit and MVC Storefront (and other sites I've built) that no matter what you think now, information about user interactions with your "products" is paramount to the business guys. There's so many metrics to capture - it's nuts.
I'll save you all the stuff I've been through - what's by far been the most successful for me is just creating an Order object with "NotCheckedOut" status and then adding items to it and the user adds items. This lets users have more than one cart and allows you to mine the tar out of the Orders table. It also is quite easy to transact the order - just change the status.
Persisting "as they go" also allows the user to come back and finish the cart off if they can't, for some reason. Forgiveness is massive with eCommerce.
Cookies suck, session sucks, Profile is attached to the notion of a user and it hits the DB so you might as well use the DB.
You might think you don't want to do this - but you need to trust me and know that you WILL indeed need to feed the stats wonks some data later. I promise you.
I have considered what you are suggesting but have not had a client project yet to try it. The closest actually is a shopping list that you can find here...
http://www.scottcommonsense.com/toolbox.aspx
Click on Grocery Checklist to open the window. It does use ASPX, but only to manage the JS references placed on the page. The rest is done via AJAX using web services.
Previously I built an ASP.NET 2.0 site for a commerce site which used anon/auth cookies automatically. Each provides you with a GUID value which you can use to identify a user which is then associated with data in your database. I wanted the auth cookies so a user could move to different computers; work, home, etc. I avoided using the Profile fields to hold onto a complex ShoppingBasket object which was popular during the time in all the ASP.NET 2.0 books. I did not want to deal with "magic" serialization issues as the data structure changed over time. I prefer to manage db schema changes with update/alter scripts synced with software changes.
With the anon/auth cookies identifying the user on the client you can use the ASP.NET AJAX client-side to call the authentication web services using the JS proxies that are provided for you as a part of ASP.NET. You need to implement the Membership API to at least authenticate the user. The rest of the provider implementation can throw a NotImplementedException safely. You can then use your own custom ASMX web services via AJAX (see ScriptReference attribute) and update the pages with server-side data. You can completely do away with ASPX pages and just use static HTML/CSS/JS if you like.
The one big caveat is memory leaks in JS. Staying on the same page a long time increases your potential issue with memory leaks. It is a risk you can minimize by testing for long sessions and using tools like Firebug and others to look for memory leaks. Use the JS Lint tool as well as it will help identify major problems as you go.
I'd be inclined to store it as a session object. This is because you're not concerned with abandoned carts, and can therefore remove the overhead of storing it in the database as it's not necessary (not to mention that you'd also need some kind of cleanup routine to remove abandoned carts from the database).
However, if you'd like users to be able to persist their carts, then the database option is better. This way, a user who is logged in will have their cart saved across sessions (so when they come back to the site and login, their cart will be restored).
You could also use a combination of the two. Users who come to the site use the session-based cart by default. When they log in, all items are moved from the session-based cart to a database-based cart, and any subsequent cart activity is applied directly to the database.
In the DB tied to whatever you're using for sessions (db/memcache sessions, signed cookies) or to an authenticated user.
Store it in the database.
Do you envision folks needing to be able to start on one machine (e.g. their work PC) but continue/finsih from a different machine (e.g. home PC)? If so, the answer is obvious.
If you don't care about abandoned carts and have things in place for someone messing with the data on the client side... I think a cookie would be good -- especially if it's just a cookie of JSON data.
I'd use an (encrypted) cookie on the client which holds the ID of the users basket. Unless it's a really busy site then abandoned baskets won't fill up the database by too much, and you can run a regular admin task to clear the abandoned orders down if you care that much. Also doing it this way the user will keep their order if they close their browser and go away, a basket in the session would be cleared at this point..
Finally this means that you don't have to worry about writing code to deal with de/serialising the data from a client-side cookie, while later worrying about actually putting that data into the database when it gets converted into an order (too many points of failure for my liking)..
Without knowing the platform I can't give a direct answer. However, since you don't care about abandoned carts, then I would differ from my colleagues here and suggest storing it on the client. Why store it in the database if you don't care if it's abandoned?
Then again, it does depend on the size of the object you're storing -- cookies have their limits after all.
Edit: Ahh, asp.net MVC? Why not use the profile system? You can enable an anonymous profile if you don't want to bother making them log in
I'd say store the state somewhere on the server and correlate it to the user's session. While a cookie could ostensibly be an equal place to store things, if you consider security and data size, keeping as much data on the server as possible becomes a good thing.
For example, in a public terminal setting, would it be OK for someone to look at the contents of the cookie and see the list? If so, cookie's fine; if not, you'll just want an ID that links the user to the data. Doing that would also allow you to ensure the user is authenticated to the site in order to get to that data rather than storing everything on the machine - they'd need some form of credentials as well as the session identifier.
From a size perspective, sure, you're not going to be too concerned about a 4K cookie or something for a browser/broadband user, but if one of your targets is to allow a mobile phone or BlackBerry (not on 3G) to connect and have a snappy experience (and not get billed for the data), minimizing the amount of data getting passed to the client will be key.
The server storage also gives you some flexibility mentioned in some of the other answers - the user can save their cart on one machine and resume working with it on another; you can tie the cart to some form of credentials (rather than a transient session) and persist the cart long after the user has cleared their cookies; you get a little more in the way of fault tolerance - if the user's browser crashes, the site still has the data safe and sound.
If fault tolerance is important, you'll need some sort of persistent store like a database. If not, in application memory is probably fine, but you'll lose data if the app restarts. If you're in a farm environment, the store has to be centrally accessible, so you're again looking at a database.
Whether you choose to key by transient session or by credentials is going to depend on whether the users can save their data and come back later to get it. Transient session will eventually get cleaned up as "abandoned," and maybe that's OK. Tying to a user profile will let the user keep their data and explicitly abandon it. Either way, I'd make use of some sort of backing store like a database for fault tolerance and central accessibility. (Or maybe I'm overengineering the solution?)
If you care about supporting users without Javascript enabled, then the server side sessions will let you use URL rewriting.
If a relatively short time-out (around 2 hours, depending on your server config) is OK for the cart, then I'd say the server-side session. It's faster and more efficient than accessing the DB.
If you need a longer persistence (say some users like to leave and come back the next day), then store it in a cookie that is tamper-evident (use encryption or hashes).