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TurboGears: Python on Rails?
gcantallopsr writes "If you liked Ruby on Rails and its 15m intro video (.mov) you will probably like TurboGears and its 20 minute wiki tutorial. (.mov) It shows you the development of a simple wiki in just 20 minutes, and there is a text version of the tutorial. TurboGears uses Python, SQLObject, CherryPy, Kid, MochiKit and some extra pythonic glue to help you to (in their own words) 'Create a database-driven, ready-to-extend application in minutes. All with designer friendly templates, easy AJAX on the browser side and on the server side, not a single SQL query in sight with code that is as natural as writing a function.'"
Why is this an advantage?
What software do people use for making these neat videos? (I realise this is bordering on off-topic :) )
Believe with me, my saplings.
Amazon don't use J2EE most of it is written in C/C++.
I'm sure there's a Google engineer chuckling at the thought of using J2EE for their entire system. If anything Google are quite varied in what languages they use I expect, like any sensible company. If your too tied to a single language, your screwed in the long term.
Java != Panacea.
Peon.
Ok, so some of these tools are not suitable for running Amazon. But guess what - most people are not running Amazon! A lot of people don't have the development resources that amazon has, either, so what they are really looking for is a sweet spot that lets them get going quickly, and will grow within reason.
I'm still mulling it over and working on it, but I talk some about "scaling down" in this article:
http://dedasys.com/articles/scalable_systems.html
You're right of course that you don't want stuff that falls over the first time traffic spikes a bit, but you absolutely must have something that you can use to produce a functional product. You can have the fanciest, most scalable system out there, but if you spend two months twiddling with XML config files, things just aren't going to work out.
http://www.welton.it/davidw/
I'm definitely not an expert in Python, in fact I've only ever given it a cursory look. However that tutorial was damn impressive. Obviously he had some prior knowlege of Python and using TurboGears but it is really not all that difficult to build something like a Wiki using that framework. As far as web work I've slowly become disenchanted with PHP. It's a good language to be sure but it's simplicity is short-lived. As you want to do more complex things you end up having to work around PHP more than you get to benefit from it. A large web project in PHP ends up structured like a project of similar size in Perl or Python. Between TurboGears on Python and Ruby on Rails it looks like I have some reading to do.
I'm a loner Dottie, a Rebel.
if you want to do something for your professional career, don't waste your time with those kind of frameworks.
If you want to do something for your professional career, get familiar with as varied a collection of tools as you can. Know the pros and cons of each. Actually test their performance, make toy projects, steal ideas and patterns. Be opinionated, but prepared to honestly choose the best tool for the job you're given, and to explain why it is the best, to suits and to techies. A few hours getting to know something new is never wasted.
I believe posters are recognized by their sig. So I made one.
new Weblog(); new Wiki(); tadaaah!
If imitation is the sincerest form of flattery then David Heinemeier Hansson must be blushing right now. His framework has insipired every other language proponent to make a rails like framework. There is trails in java, django in python (and now turbogears), there are at least two PHP frameworks and even a .NET one. I think somehow David touched a nerve someplace and produced something really beautiful.
.NET people are resorting to code generation to try and mimic some of the functionality of rails.
Much of what makes rails great is the highly dynamic nature of Ruby itself. Do yourself a favor and read the activerecord source code. Even if you don't know ruby it's an interesting lesson on how to take advantage of dynamic scripting languages. I am sure python and PHP could also do something like this but the Java and
To me it seems like a silly exercise to replicate rails in python or what have you. Ruby is easy to pick up and a nice language to boot. Why bother really? Just learn ruby and get on board.
evil is as evil does
Wrong.
If you're building Amazon or a simular service (million visits/day) everything scales. I don't know the exact budget the Amazon portals had, but buying Guido von Rossum or Larry Wall and ten of their favorite programmers for life would've probalby been less than a month of amazons electricity bill.
If I were to rebuild Amazon I'd actually consider Python. If the VM doesn't cut it, I'd hire 20 programmers to optimize it. Which, btw, I don't think would be neccesary.
Another scenario is even more realistic. MySQL sucks for certain purposes. But if a certain OSS CMS I like only runs with it, but the project is big enough to imperatively require Postgres or Firebird, then the projects budget should allow to patch in support for that DB.
We suffer more in our imagination than in reality. - Seneca
stored procedures and triggers *are* code - its a hack to follow the "do it all in the database" mentality.
no kidding, they are indeed code, but this code mostly is on the other side of the database pipe/socket/stream/ which is very important. for example if you update 500 000 records then a database side trigger is affordable
dont get me wrong here, i like the sql to object and vica versa mappings, the idea is cool
choose the right thing for the right job.
and no, i dont think we need another wiki
I'd tell you the chances of this story being a dupe, but you wouldn't like it.
Slashdot itself uses Apache/mod_perl/MySQL, and there's little between mod_perl and mod_python in terms of performance. Slashdot handles 3 million pages per day without any trouble. Does Slashdot not count as a 'large site'?
The idea that J2EE is the only system that can handle high traffic sites is a myth.
Google uses python all the time.
I am trolling
Yeah, that's the part that gets me wondering. People keep talking about hiding away the SQL. But if they don't want SQL, then why are they using an SQL RDBMS in the first place?
;) ), rather than it being neatly stored with 1000 other nonrelated SQL statements (as functions or otherwise).
Shouldn't they be using something else then? Otherwise they'll get the drawbacks of using an SQL database but fewer of the advantages. What happens if performance in a particular area is not good enough?
Say you want to store a session in a database and you want it to expire after X seconds of inactivity.
A simplistic method would be to update the session row each time there's activity. But this would cause lots of writes which would be slower in most proper databases (those that actually write to disk for writes). An alternative would be the databases equivalent of "update sessiontable set lastactive=now() where sessionid='$sessionid' and lastactive+'1 second' <= now()".
With this, you could have thousands of hits per second but only 1 forced write to disk per second due to that query.
How would you achieve this when you're so abstracted away from the SQL database? And it might look strange to others when you try to do the same thing N layers above the database. I'm sure there are better examples.
Those sort of queries are likely to look different on different RDBMSes. You could make a function that looks the same, but someone still is going to have to write the SQL for portability (and sometimes bad luck, it's not possible - DB doesn't support functions or that sort of function). Also, if only the program's session module does that stuff, then what's so bad about leaving the SQL in there? At least then there'll be some context to understand the SQL (and whether it's wrong or right
Sure it's ugly. But if people want it all so elegant and clean maybe they should write _everything_ in some version of Lisp, and not interface with the rest of the ugly real world.
if it's mixing in dynamic SQL queries there's a good chance it also has SQL injection holes.
I'll take that "if" to mean you haven't read the documentation and didn't actually watch the video. Stop frothing at the mouth about SQL injection holes. If you had bothered to watch the fucking video (which you didn't), you'd notice it has specific mechanisms to deal with them.
Also, its main purpose isn't to "catch bugs", it's to make things easier on the programmer. Abstraction toolkits like this are good. God forbid someone make things easier.
I call BS. First off, SQL is a set-based language. Very rarely do you need to loop over a result set (if you find yourself looping in SQL code, you're not thinking hard enough). Whatever "loop and operate" action you'd take with Python can be done quicker and more efficiently with SQL code than with app code.
And I call BS on your BS, because you didn't actually read what you were responding to. I'm beginning to notice a pattern here, first you start frothing at the mouth based on speculation from not having RTFV (video), then you do it for not reading the comment you're responding to. They specifically used the descriptive words "powerful" and "easier" not "faster." The issue isn't effeciency, no one is claiming that TurboGears produces the most effecient code. The whole purpose of TurboGears is to make things easier on the programmer, which is what this does. Designing the logic within python, which actually does allow you to do quite a bit more in terms of 'business logic', makes things easier.
Finally, while it may be "easier" for a developer proficient in Python and not the SQL dialect used by your chosen DBMS, that's a cop-out. As so many people are so fond of saying, you should use the right tool for the job
No, even for someone very proficient in SQL it's still easier in Python due to these bindings. Of course, not having actually read anything about TurboGears (e.g. the documentation) and engaging and rampant speculation and all, you wouldn't know that.
And they ARE using the right tool for the right job, you should follow your own damn advice. TurboGears is designed for jobs where EASE is a priority over effeciency. GUESS WHAT, effeciency isn't always the #1 priority, genius.
You speak boldly, but you can't read worth shit, excercise critical thinking skills nor even follow your own advice.
I've intentionally ignored the problem of database portability, because a) you should be using stored procedures, which means you'll want to port them yourself anyway for maximum benefit, b) you should be using a proper DBI layer such that you just have to tell it, "I'm using Oracle now instead of Postgres, do the right thing", and c) because you're using stored procedures, you won't be switching to a DBMS that doesn't support the
A isn't even a "reason", it's just a circular statement. "You'll want to do it because you'll want to."
B isn't valid either, which leads me to believe that you're not actually a database programmer, since DBI layers don't just magically translate from one proprietarism to another. If you DO use an sql stored procedure, you're forced to stick to strict standards, otherwise the DBI layer becomes useless.
C is just a lame excuse to bash MySQL, it's not even a real reason. Keep on frothing there, buddy.
J2EE based web services are 900 pound gorillas. Sure, amazon etc use it, but I don't spend my day making amazon.com's. I spend it getting requests from various departments for single purpose programs that are web based (so we don't have to maintain yet another fat client on the desktop). These simplier frameworks make it possible to make quality web applications quickly. Most of these programs are just a varation on a theme. 2 or 3 tables with maybe a foreign key and 3 or 4 web pages. These frameworks make it possible for me to give them a finished application in a couple of hours so I can spend my time doing more important stuff.
If an officer ever threatens to taze you, say you have a pacemaker.
Point the first: nothing that you mentioned has yet been removed from python.
Point the second: map and reduce are on the suggested drop list in favor of other functional programming constructs like list comprehensions and generators that do the exact same thing with cleaner syntax. Because that's what python is about
Point the third: please explain how anonymous closures are superior to lambda constructs, list comprehensions, or generators each used in the appropriate context.
I think you'll find there's not too much difference between Python and Ruby in this respect. In Ruby, code such as this:
is just about equivalent to this in Python:
Ruby and Python take different approaches to the same problem, but I'd hesitate in saying one was clearly superior to another.
That's because list comprehensions, generators, and inner functions do the same thing in a more Pythonic way. No functionality will be lost with the disappearance of lambda, map, filter, etc.