What makes Python stand out for use in web development? What are some examples of highly successful uses of Python on the web?
Django is, IMHO, one of the major benefits of using Python. Model your domain, code your classes, and voila, your ORM is done, and you can focus on the UI. Add in the ease of templating with the built-in templating language (or one of many others you can use as well), and it becomes very easy to whip up effective web applications in no time. Throw in the built-in admin interface, and it's a no-brainer.
Certainly one successful use of Python on the web is Google App Engine. Site authors write code in (a slightly restricted subset of) Python, which is then executed by the App Engine servers in a distributed and scalable manner.
Quotes about Python:
"Python is fast enough for our site
and allows us to produce maintainable
features in record times, with a
minimum of developers," said Cuong Do,
Software Architect, YouTube.com.
YouTube uses a lot of Python and is probably the best example of a Python success story.
A great example of a Django success story is the Washington Post, who recently shared a big list of applications they have developed:
http://push.cx/2009/washington-post-update
www.lawrence.com and www.ljworld.com are two of the first sites to use Django (before it was even open source).
djangositeoftheweek.com has a bunch of good case studies.
www.everyblock.com is another great example.
Finally, http://www.djangosites.org/ links to nearly 2,000 other Django powered sites.
Short anwser: the diversity of tools readily available and freedom of choice.
This sounds like a simple question but which it really isn't. While Python is very good for web development and this has been shown by the, oh so famous, Google App Engine, Plone and Django. One has to point out that the development way in Python requires a lot more from the developer than PHP but it gives a lot more to the mix as well.
The entry level on actually producing something is higher. This is because there are bunch of different tools for doing web development with Python. Choosing the web development framework can be a hard decision for an inexperienced developer.
Having a lot of different tools is a two edged sword. To some extent it brings you the freedom of choice to pick the one you might want but then again how do you really know which one is good for what you're doing. This brings me to my point. Python stands out from the mass by not having a standard or de facto web development library. While this is pretty much against the principle of having only one simple way of doing on thing it also brings us a wide variety of different tools with different kind of design choices. At first this might feel very frustrating because it would be so much easier if somebody had made the choice for you but now that you're left to make the choice you actually might have to think about what you're doing and what would fit. ...or you might just end up picking one and blowing your head off after you've realized that you made the wrong choice. Anyway you end up, you've made the choice and no one else.
Furthermore,
Python is both strong in web and in data analytics and machine learning. For example scikit, sci-py and numpy are very strong. In some cases, it can be very interesting to have the both elements on the same server.
For example http://rankmytweet.com uses this a lot.
trac(bug tracker) and moinmoin(wiki) are too web based python tools that I find invaluable.
GNU Mailman is another project written in python that is widely successful.
As many have pointed out, Django is a great reason to use Python...so in order to figure out why Python is great for web development, the best bet is to look at why it is a good language to build a framework like Django.
IMHO Python combines the cleanest, or at least one of the cleanest, metaprogramming models of any language with a very pure object orientation. This not only makes it possible to write extremely general abstractions that are easy to use, but also allows the abstractions to combine relatively cleanly with others. This is harder to do in languages that take a code-generation based approach to metaprogramming (e.g. Ruby).
Dynamic languages are in general good for web apps because the speed of development. Python in particular has two advantages over most of them:
"batteries included" means lots of available libraries
Django. For me this is the only reason why i use Python instead of Lua (which i like a lot more).
Besides the frameworks...
Python's pervasive support for Unicode should make i18n much smoother.
A sane namespace system makes debugging much nicer, because it's typically easier to find where things are defined.
Python's inability to function as a standalone templating language should discourage the mixture of HTML with model code
Great standard library
Other examples of Python sites are Reddit and YouTube.
Related
We have an in house developed web-based admin console that uses a combination of C CGI and Perl scripts to administer our mail server stack. Of late we have been thinking of cleaning up the code (well, replacing most of it), making the implementation more secure, and improving the overall behavior.
I don't have much programming knowledge, but I use Ruby on and off (mainly for writing erb templates), and hence was thinking of using ruby/rails for developing such an app (off-duty for now, I also need to learn stuff !).
Before blindly picking up a language though, what would you folks suggest ? Please let me know if this is too vague a question, I'll try to supply more information, if needed.
Have you considered writing your applications as Webmin modules?
You get a lot of stuff for free when you do so (users and groups, tons of security features, a pretty big variety of helper functions related to config files, and tons of existing code for most aspects of a UNIX/Linux system). You also get a lot of stuff for nearly free, like action logging, packages and updates via wbm or apt or yum, an online help system, etc.
There are some cons, as well. It's an old codebase, so it has some clunky bits in the API among other places. A lot of the old modules can be a bit hard to grok if you're not an old-school Perl programmer. But, it's a well-maintained codebase, and it's been banged on by millions of users for over a dozen years. It's pretty robust. The UI isn't beautiful, but it is relatively theme-able, and if you're distributing a minimized version it becomes easier to customize the UI.
I suspect you can be up and running a lot faster than starting from scratch or using most existing frameworks that aren't targeted specifically to building systems management interfaces the way Webmin is.
Also, it's BSD licensed, so you can do whatever you want with it, including building a custom commercial app with it (hundreds of companies have done so over the years).
If you already know a bit of ruby, then there's no reason not to use that.
If you're interested specifically in learning another language, then what you're trying to do could be done in pretty much any language/framework, it's just a matter of which one you want to learn.
Without knowing much about your existing application I'd say that this effectively boils down to "which language do you like to work with?".
Python and Ruby are both mature languages with ample library infrastructure. They also boast popular, similar web application frameworks namely Django and Ruby-on-Rails respectively.
Since you are porting an existing Perl app(lets) it may be worthwhile to note that Ruby is relatively more similar to Perl. Not surprising given that Ruby was influenced "primarily by Perl, Smalltalk, Eiffel and Lisp".
django has a nice admin interface
I'm making a simple web app where I have some simple python scripts that do the text crunchin g I need - but I'm not quite sure how to interface it with a client who'd only want to see some HTML forms.
There's so many different server side frameworks out there - but I don't think I need anything too heavy duty - just a mechanism to accept data from the forms that the user fills in, and feed it to my Python code and back.
Could someone suggest what tools I should look into and what design paradigms I should follow? Simple pointers to different references around the web with a single line about their significance would also help.
Best.
At the moment, the best lightweight and yet very powerful framework for python IMO is Flask. If you want form abstraction there is a WTFlask plugin for it which is WTForms adapted for flask - http://flask.pocoo.org/.
Web2py is also a very good framework for starters because it has helpers and wizards for creating/running an application, and also has something like an admin interface, offering an On-line IDE functionality. - http://www.web2py.com/
I proposed these two frameworks because you can start fast with them, they both have good documentation, both are powerful yet easy and they are pretty friendly for beginners.
Not normally supported with cheap hosting, but mod_python on apache might be right up your alley.
You could also have html talk to python through cgi (Which has been the way of doing it for years before php came along).
The standard Design pattern commonly seen in web apps is Model-View-Controller, so google around.
I've used Django (heavy and something of a non-trivial initial learning curve), and web.py (very small & simple), and over the past year, I've been pretty happy using tornado.
People can argue about the async details, but that's not even why I use it. It's pretty fast, it's super quick to get started with, it comes with examples that get you doing things quickly, and -- most important to me -- It's a web server and framework in one, which means you don't have to muck with mod_python vs mod_wsgi vs cgi vs fcgi vs whatever. Deployment is really easy.
I'm lucky enough to have full control over the architecture of my company's app, and I've decided to scrap our prototype written in Ruby/Rails and start afresh in Python. This is for a few reasons: I want to learn Python, I prefer the syntax and I've basically said "F**k it, let's do it."
So, baring in mind this is going to be a pretty intensive app, I'd like to hear your opinions on the following:
Generic web frameworks
ORM/Database Layer (perhaps to work with MongoDB)
RESTful API w/ oAuth/xAuth authentication
Testing/BDD support
Message queue (I'd like to keep this in Python if possible)
The API is going to need to interface with a Clojure app to handle some internal data stuff, and interface with the message queue, so if it's not Python it'd be great to have some libraries to it.
TDD/BDD is very important to me, so the more tested, the better!
It'll be really interesting to read your thoughts on this. Much appreciated.
My best,
Jamie
Frameworks
OK, so I'm a little biased here as I currently make extensive use of Django and organise the Django User Group in London so bear that in mind when reading the following.
Start with Django because it's a great gateway drug. Lots of documentation and literature, a very active community of people to talk to and lots of example code around the web.
That's a completely non-technical reason. Pylons is probably purer in terms of Python philosophy (being much more a collection of discrete bits and pieces) but lots of the technical stuff is personal preference, at least until you get into Python more. Compare the very active Django tag on Stack Overflow with that of pylons or turbogears though and I'd argue getting started is simply easier with Django irrespective of anything to do with code.
Personally I default to Django, but find that an increasing amount of time I actually opt for writing using simpler micro frameworks (think Sinatra rather than Rails). Lots of things to choose from (good list here, http://fewagainstmany.com/blog/python-micro-frameworks-are-all-the-rage). I tend to use MNML (because I wrote parts of it and it's tiny) but others are actively developed. I tend to do this for small, stupid web services which are then strung together with a Django project in the middle serving people.
Worth noting here is appengine. You have to work within it's limitations and it's not designed for everything but it's a great way to just play with Python and get something up and working quickly. It makes a great testbed for learning and experimentation.
Mongo/ORM
On the MongoDB front you'll likely want to look at the basic python mongo library ( http://api.mongodb.org/python/ ) first to see if it has everything you need. If you really do want something a little more ORM like then mongoengine (http://hmarr.com/mongoengine/) might be what you're looking for. A bunch of folks are also working on making Django specifically integrate more seamlessly with nosql backends. Some of that is for future Django releases, but django-norel ( http://www.allbuttonspressed.com/projects/django-nonrel) has code now.
For relational data SQLAlchemy ( http://www.sqlalchemy.org/) is good if you want something standalone. Django's ORM is also excellent if you're using Django.
API
The most official Oauth library is python-oauth2 ( http://github.com/simplegeo/python-oauth2), which handily has a Django example as part of it's docs.
Piston ( http://bitbucket.org/jespern/django-piston/wiki/Home) is a Django app which provides lots of tools for building APIs. It has the advantage of being pretty active and well maintained and in production all over the place. Other projects exist too, including Dagny ( http://zacharyvoase.github.com/dagny/) which is an early attempt to create something akin to RESTful resources in Rails.
In reality any Python framework (or even just raw WSGI code) should be reasonably good for this sort of task.
Testing
Python has unittest as part of it's standard library, and unittest2 is in python 2.7 (but backported to previous versions too http://pypi.python.org/pypi/unittest2/0.1.4). Some people also like Nose ( http://code.google.com/p/python-nose/), which is an alternative test runner with some additional features. Twill ( http://twill.idyll.org/) is also nice, it's a "a simple scripting language for Web browsing", so handy for some functional testing. Freshen ( http://github.com/rlisagor/freshen) is a port of cucumber to Python. I haven't yet gotten round to using this in anger, but a quick look now suggests it's much better than when I last looked.
I actually also use Ruby for high level testing of Python apps and apis because I love the combination of celerity and cucumber. But I'm weird and get funny looks from other Python people for this.
Message Queues
For a message queue, whatever language I'm using, I now always use RabbitMQ. I've had some success with stompserver in the past but Rabbit is awesome. Don't worry that it's not itself written in Python, neither is PostgresSQL, Nginx or MongoDB - all for good reason. What you care about are the libraries available. What you're looking for here is py-amqplib ( http://barryp.org/software/py-amqplib/) which is a low level library for talking amqp (the protocol for talking to rabbit as well as other message queues). I've also used Carrot ( http://github.com/ask/carrot/), which is easier to get started with and provides a nicer API. Think bunny in Ruby if you're familiar with that.
Environment
Whatever bits and pieces you decide to use from the Python ecosystem I'd recommend getting to who pip and virtualenv ( http://clemesha.org/blog/2009/jul/05/modern-python-hacker-tools-virtualenv-fabric-pip/ - note that fabric is also cool, but not essential and these docs are out of date on that tool). Think about using Ruby without gem, bundler or rvm and you'll be in the right direction.
Ok, you might be making a mistake, the same one I made when I started with python.
Before you decide on a thing like django, which is an excellent, yet atypical python web framework, spend an night cuddled up with:
This, is a good start. Make sure you do A little Werkzeug watching , Then check out
some classic WebOb. Maybe, if you feel the fire in the blood, and you might, wsgi is a bit flawed, but only to the gods, check out Flask
I'm not saying use it, Django is beautiful too, but if you don't know python, and you go through django, you run the risk of learning a framework.
WSGI is super straightforward. You'll find out about Paste, and Pastescript, and Pylons.
Then, make your decision. It'll be much easier learning stuff doing bare bones wsgi or Flask, stuff like variable assignment, using the interpreter, style concerns, testing, on 3 files for a couple of nights, instead of django. Take 2 nights. Then you'll see the great similarity between python web frameworks, instead of the differences. Hell, you might even roll with Flask.
Just some advice, I did the same thing with ruby, going in through Rails, and... well, strong words were said.
Language, then basic wsgi and testing, then pick your framework and roll
I'm new to python myself, and plan to get more in depth with it this year. I've had a few false starts at this, but always professional needs bring me back to PHP. The few times I've done some development, I've had really good experiences with web2py as a python framework. It's quite well done, and complete in features, while still being extremely lightweight. The database layer seems to be very flexible and mature.
As for TDD/BDD and the rest of your questions, I don't have any experience with python options, but would be interested to hear what others say.
I am using Twisted Framework based Nevow library for python based web app.
All your criteria fit into this single framework.
I recall when I first read Pragmatic Programmer that they suggested using scripting languages to make you a more productive programmer.
I am in a quandary putting this into practice.
I want to know specific ways that using Python or Ruby can make me a more productive .NET developer.
One specific way per answer, and even better if you can say whether I could use Python or Ruby or Both for it.
See standard format below.
IronPython / IronRuby
IronPython in Action will do a better job explaining this (and exactly how best to use IronPython) that can possibly be accommodated in a SO answer. I'm biased -- I was a tech reviewer and am a friend of one of the authors -- but objectively think it's a great book. (No idea if IronRuby is blessed with a similarly wonderful book, yet).
As you want "one specific way per answer" (incompatible with SO, which STRONGLY discourages a poster posting 25 different answers if they have 25 "specific ways" to indicate...!-): prototyping in order to explore some specific assembly or collection thereof that you're unfamiliar with (to check if you've understood their docs right and how to perform certain tasks) is an order of magnitude more productive in IronPython than in C#, as you can explore interactively and compilation is instantaneous and as-needed. (Have not tried IronRuby but I'll assume it can work in a roughly equivalent way and speed).
Less Code
I think productivity is direct result on how proficient you are in a specific language. That said the terseness of a language like Python might save some time on getting certain things done.
If I compare how much less code I have to write for simple administration scripts (e.g. clean-up of old files) compared to .NET code there is certain amount of productivity gain. (Plus it is more fun which also helps getting the job done)
Advanced Text Processing
Traditional strengths of awk and perl. You can just glue together a bunch of regular expressions to create a simple data-mining system on the go.
Learning a new language gives you knowledge that you can bring back to any programming language. Here are some things you'd learn.
Add functionality to your objects on the fly.
Mix in modules.
Pass a chunk of code around.
Figure out how to do more with less code: ruby -e "puts 'hello world'"
C# can do some of these things, but a fresh perspective might bring you one step closer to automating your breakfast.
Embedding a script engine
Use of IronPython for a scripting engine inside your .NET application. For example enabling end-users of your application to change customizable parts with a full fledge language such as Python.
A possible example might be to expose custom logic to end-users for a work flow engine.
Quick Prototyping - Both
In the simplest cases when firing a python interpreter and writing a line or two is way faster than creating a new project in visual studio.
And you can use ruby to. Or lua, or evel perl, whatever. The point is implicit typing and light-weight feel.
Cross platform
Compared to .NET a simple script Python is more easily ported to other platforms such as Linux. Although possible to achieve the same with the likes of Mono it simpler to run a Python script file on different platforms.
Processing received Email
Python has built-in support for POP3 and IMAP where the standard .NET framework doesn't. Useful for automating email triggered tasks.
I want to start writing a http proxy that will modify responses according to some rules/filters I will configure. However, before I start coding it, I want to make sure I'm making the right choice in going with Python. Later, this tool would have to be able to process a lot of requests, so, I would like to know I can count on it later on to be able to perform when "push comes to shove".
As long as the bulk of the processing uses Python's built-in modules it should be fine as far as performance. The biggest strength of Python is its clear syntax and ease of testing/maintainability. If you find that one section of your code is slowing down the process, you can rewrite that section and use it as a C module, while keeping the bulk of your control code in Python.
However if you're looking to make the most optimized Python Code you may want to check out this SO post.
Yes, I think you will find Python to be perfectly adequate for your needs. There's a huge number of web frameworks, WSGI libraries, etc. to choose from, or learn from when building your own.
There's an interesting post on the Python History blog about how Python was supporting high performance websites in 1996.
This will depend on the library you use more than the language itself. The twisted framework is known to scale well.
Here's a proxy server example in python/twisted to get you started.
Bottomline: choose your third party tools wisely and I'm sure you'll be fine.
Python performs pretty well for most tasks, but you'll need to change the way you program if you're used to other languages. See Python is not Java for more info.
If plain old CPython doesn't give the performance you need, you have other options as well.
As has been mentioned, you can extend it in C (using a tool like swig or Pyrex). I also hear good things about PyPy as well, but bear in mind that it uses a restricted subset of Python. Lastly, a lot of people use psyco to speed up performance.