python semantic proxy/server, which framework to use? - python

This year me and a friend have to make a project for the final year of university. The plan is to make a proxy/sever that allows to store ontologies and RDF's, by this way this data is "chained" to a web, so you can make a request for that web and the proxy will send you the homepage with metadata.
We have been thinking to use python and rdflib, and for the web we don't know which framework is the best. We thought of django, but we think that is very big for our purpose, and we decided that webpy or web2py is a better option.
We don't have any python coding experience, this will be our very first time. We have been always programming in c++ and java.
So taking into account everything we've mentioned our question is, which would be the best web framework for our project? And will rdflib suit fine with this framework?
Thanks :)

I have developed several Web applications with Python framworks consuming RDF data. The choice always depends on the performance needed and the amount of data you'll have to handle.
If the number of triples you'll handle is in the magnitude of few thousands then you can easily put together a framework with RDFlib + Django. I have used this choice with toy applications but as soon as you have to deal with lots of data you'll realise that it simply doesn't scale. Not because of Django, the main problem is RDFlib's implementation of a triple store - it is not great.
If you're familiar with C/C++ I recommend you to have a look at Redland libraries. They are written in C and you have bindings for Python so you can still develop your Web layer with Django and pull out RDF data with Python. We do this quite a lot and it normally works. This option will scale a bit more but won't be great either.
In case your data grows to millions of triples then I recommend you to go for a Scalable Triple store. You can access them through SPARQL and HTTP. My choice is always 4store. Here you have a Python client to issue queries and assert/remove data 4store Python Client

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Flask Custom Login and Template Rendering

I am new to learning Python for web development and have decided to go with Flask as my framework of choice as of now. I have chosen this primarily for its bare-bones approach on web development and I want to make as much of my web app custom and on my own as possible. I have made a very basic MVC framework in PHP and would like to make something like this in Python. I was researching some ways to interact with a database and add user login/register support and my original thoughts were that I wanted to do this all custom with my own methods and objects and what not. Similar to how I have done in PHP, so I can learn as much about developing my own back-end efficiently for long term production projects. In some research I found the basic objects in Flask such as Login Manager, Login-Form and Flask-Admin, etc. I don't like the idea of using these nicely packaged things that I have very little control over and have not dev'd custom.
Using that kind of stuff I also feel that I am not learning how all of that stuff works on the lowest level so I could not reproduce some of the benefits they are giving me later on in life when project circumstances change and maximum flexibility, customization, maintainability, and efficiency is needed. Obviously I am not in that position right now, but I DO know how to write this back end stuff in PHP and am just wondering if that means anything as far as managing sessions and Authentication on my own in Python/Flask, or if my thinking is totally out of ocontext and its not even close to managing the same stuff.
It is a really great idea to learn how authentication works at a low level -- it's particularly important as many people never learn this stuff, and it's quite interesting!
What I'd recommend you do is take a look at the official Flask tutorial (http://flask.pocoo.org/docs/0.10/tutorial/), as it covers a lot of this (working directly with sessions, etc.).
What I would not recommend, however, is using this sort of thing in production.
Using your own authentication code is almost never a good idea -- it's much better to rely on a well supported library that has been audited by other people for security issues.
In the Flask world you've got a couple choices:
Flask-Login: https://flask-login.readthedocs.org/en/latest/
Flask-Security: https://pythonhosted.org/Flask-Security/
Flask-Stormpath: http://flask-stormpath.readthedocs.org/en/latest/
Of those 3, I really like Flask-Stormpath -- but I'm super biased as I wrote it =)
Flask-Stormpath supports the widest array of customization / etc., and allows you to do whatever you want with it.
Hope that helps!
Flask official doc have some app examples. One of them is MiniTwit a micro Twitter clone. As it is a complete app, you could found much of what you're looking for. If you want to make something greater, try Full Stack Python Flask tutorial

How do people usually operate information on server database?

I have a server with a database, the server will listen for http requests, and using JSONs for
data transferring.
Currently, what my server code(python) mainly do is read the JSON file, convert it to SQL and make some modifications to the database. And the function of the server, as I see, is only like a converter between JSON and SQL. Is this the right procedure that people usually do?
Then I come up with another idea, I can define a class for user information and every user's information in the database is an instance of that class. When I get the JSON file, first I put it into the instance, do some operation and then put it into the database. In my understanding, it adds a language layer between the http request and the database.
The question is, what do people usually do?
The answer is: people do usually that, what they need to do. The layer between database and client normally provides a higher level api, to make the request independent from the actual database. But how this higher level looks like depends on the application you have.
People usually make use of a Web framework, instead of implementing the basic machinery themselves as you are doing.
That is: Python i s a great language that easily allows one to translate "json into sql" with a small amount of code - and it is great for learning. If you are doing this for educational purposes, it is a nice project to continue fiddling with, and maybe you can have some nice ideas in this answer and in others.
But for "real world" usage, the apparent simple plan comes up with real world issues. Tens or even hundreds of them. How to proper separate html/css template from content from core logic, how to deal with many, many aspects of security, etc...
Them, the frameworks come into play: a web-framewrok project is a software project that had, over the years, and soemtimes hundreds of hours of work from several contributors, thought about, and addresses all of the issues a real web application can and will face.
So, it is ok if one want to to everything from scratch if he believes he can come up with a a framework taht has distinguished capabilities not available in any existing project. And it is ok to make small projects for learning purposes. It is not ok to try to come up with something from scratch for real server production, without having a deep knowledge of all the issues involved, and knowing well at least 3, 4 frameworks.
So, now, you've got the basic understanding of a way to get to a framework - it istime to learn some of the frameworks tehmselves. Try, for example, Bottle and Flask (microframeworks), and Django (a fully featured framework for web application development), maybe Tornado (an http server, but with enough of a web framework in it to be usable, and to be very instructive)- just reading the documentation on "how to get started" with these projects, to get to a "hello world" page will lead you to lots of concepts you probably had not thought about yet.

Python frameworks for developing facebook apps

I'd like to ask you about your experiences in developing facebook applications in Python. Which of the popular web frameworks for this language you think best suits this purpose? I know "best" is a very subjective word, so I'm specifically interested in the following:
Most reusable libraries. For example one might want to automatically create accounts for new logged in facebook users, but at the same time provide an alternative username + password logging functionality. I need authentication to fit into this nicely.
Facebook applications tend to differ from CMS-like sites. They are action intensive. For more complicated use-cases, usually some kind of caching for the data fetched from Open Graph API is required in order to be able to perform some queries on local and facebook data at once (for example join some tables based on friendship relation).
I'd definitely prefer popular solutions. They just seem to be much more stable and better thought through. I've previously developed a facebook application in Grails and I as much as I liked the architecture and the general ideas, the amount of bugs and complication that I ran into was just a little bit too much. Also Groovy is still quite an exotic language to develop in, and this time I'm not going to work on my own.
I'm not new to Python, but definitely new to web development in Python. Though after the experience with Grails and all its twists and turns I doubt Python could really scare me.
I would almost undoubtedly go with Django as the easiest and most popular framework for developing any type of web applications, if there's a need for a full-stack framework.
Specifically, in regards to Django's app universe, it is plentiful with many active applications -- but that has its downfalls too. There's no standard application for any 'one' thing, but there are a few applications that will do basically 90% of all that's needed. Sometimes the code is poorly written, but most of the time, the apps work and do what they are needed to do, so there's almost no need for someone to dive right in to the code.
Narrowing down our options, I have had great luck with Omab's Django-Social-Auth, which was absolutely a snap to integrate. It required 3 variables in my settings.py and I was up and running.
The only issue might be if you do not want to use the django.contrib.auth.User model, but, if you are not thinking about using that, I would think about that decision twice :)
To narrow it down even further, pyfacebook is another option for integrating Facebook. It comes with a djangofb application so it's just drop, add to settings.py and all is well. It even comes with an example Django application as part of the distribution. I've had pretty good luck with this application, but, I still think Omab's much easier to integrate.
Finally, Facebook's own python-sdk is easy to integrate from a raw standpoint, where they just give you access to their APIs using a simple Python API. However, it seems to cater more to the AppEngine folks, so YMMV.
I've used Django for quite some time. As of late I use Jinja2 instead. No particular reason, but it's another option
If you do not want to start on Django now. Try learning Flask(which is comparatively a lot easier to begin than Django) and then start building app with Flask.

I'm learning python and am interested in using it for web-scripting. What frameworkes are out there and do I need one?

I've been learning python for use in ArcGIS and some other non-web applications. However, now that I've taken on building a personal website I am interested in using it for web development (as it is the only scripting language I currently know).
I've noticed that there are a lot of these things called "frameworks", such as Django. From what I understand they are just a collection of packages to save you from re-inventing the wheel but I don't really know how they work.
Furthermore, I do not like GUIs, if I need a framework I would like to find one that could be used through a terminal, starts out simple and can be scaled for more complexity when I'm ready. Any advice or ideas on frameworks and why I would want to use one?
The Python web frameworks have nothing to do with GUIs, and can all be used via the terminal.
The benefits of a framework, as you say, are all to do with making your life easier by supplying the components you need to build a website: the main ones are database interaction through an ORM, a templating system, and URL routing. On top of that, the big frameworks also included optional extras like user authentication, administration interface, and so on.
Personally I like Django, but your mileage may vary: I would say, though, that whatever you do with Python and the web will require some sort of framework, even if it's one of the absolute minimal ones like Flask which basically do just the routing part. There's simply no point in writing all this stuff from scratch when it's been done for you.
I'd second the post above: Django is a great framework and will save you loads of time in the long run.
Pretty much every challenge you'll come across when writing a web application will already have been solved, e.g. How do I send emails? What about an admin interface to edit the data? User security?
In my view picking the best framework is all about the ecosystem around that framework. How well used is it? Is it discussed widely on the internet? Have others encountered, and solved, the problems I'm facing?
In terms of where you start, see the Django Tutorial here:
http://docs.djangoproject.com/en/1.2/intro/tutorial01/
If you think Django offers you too much, I'd recommend that you take a look at CherryPy just to compare the different, and much simpler, approach.
With Python, you've got lots of options. To start, I would recommend looking here -- it explains the basics and provides a fairly complete list of frameworks.
If you're looking for something that starts out simple but can also handle more complexity, then you should take a look at web2py. It requires no installation or configuration, has no dependencies, and includes a web server and a relational database. It also includes an optional web-based integrated development environment and admin interface, but you can work through the terminal instead if you prefer.
It's very easy to learn and was designed for ease of use, faster development, and security. You can get a lot done with very little code thanks to the included scaffolding app along with many sensible default behaviors. As things get more complex, web2py can handle it, as it is a well-integrated full-stack framework with lots of built-in functionality, including a database abstraction layer, form handling and validation, access control, web services, and easy Ajax integration.
Personnally, I don't use any framework, I write either from scratch on BaseHTTPServer, or using WSGI (with mod_wsgi).
It is a bit long to write the skeleton, but I think it is faster (I mean at runtime), there is less constraints, and there is lesser to learn.

Will learning Django translates well into other applications?

Does anyone have experience using Python in different variaty of applications?
A little background - I am a 3D artist in an animation studio. I do programming in PHP and use Zend framework for my personal project. Python has always been a language I wanted to learn because it can be used within many applications our studio is using (3D MAX, MAYA to name a few) My supervisor knew about my web background and wanted me to create a web base time line manager for the company. From the requirement I'm expecting quite a simple backend ... so it might be a good opportunity to finally learn Python. The bulk of the work will be on AJAX for the interactive front end.
So if I learn Python with web application and Django in mind, will that limit my Python skill from applying it to other applications?
a little curious about Django features as well. How well does the framework cover in terms of web application compare to Zend? Our application is pretty basic in the back end and I would love to know if Django will be able to cover them.
authenticate against Windows active directory
quick database update via AJAX interaction (drag and drop time line mostly)
Other basic stuff like discussion forum and directory browsing/file manager
So if I learn Python with web application and Django in mind, will that limit my Python skill from applying it to other applications?
No
authenticate against Windows active directory
Yes. You may need to customize an Authentication Backend.
quick database update via AJAX interaction (drag and drop time line mostly)
Django has nothing to do with Ajax. Use piston to create pleasant RESTful API that Ajax can use.
Other basic stuff like discussion forum and directory browsing/file manager
There are many, many canned applications for Django that you can plug in and integrate.
I love python as a language - but it's not the answer to everything. I know this is throwing mud in a python group, but python has one serious limitation - the rigid source code format.
While going through a django tutorial - I noticed that you cannot insert python source code into a template, and that this was presented as a 'feature' for separating programmers and designers.
I later realized that it's a limitation of django - and any other environment where python source code might get accidentally mangled. This also includes HTML WYSIWIG editors and database based 'manglers' (like Drupal).
In my opinion it's a very serious limitation with no easy cure - especially with the need to use other tools to manage the complexity of HTML / CSS / JavaScript.
I found Django a really good way to learn python. There's very little that's quirky, magical or un-pythonic in the framework. A bit of setup and you're away, writing standard python code.

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