First off, I know similar questions have been answered, but I can't find any solutions for my particular constraints. If there is one, please point me to it.
I'm trying to start a django project. However, I can't run the development server. The problem seems to be the SQLite version. I have 3.7.17 installed, django requires 3.9 or later. So I need to upgrade it. The problem is I'm using one machine from many, used by multiple developers all working on different projects, but sharing the same global python packages. So whatever changes I need to make, need to be inside my venv. And I don't have root access on the machine. Also, I don't plan on using SQLite as the DB for the project, so if that means I can somehow bypass this requirement, that would be fine as well. However, I assume, in that case I'll need to somehow transfer the django admin app to my DB of choice as well?
Note: I'm quite new to web development or programming in general, so a dumbed down explanation would be greatly appreciated. Thanks.
My Python/Django code behaves different in the heroku production code, than on my development machine.
I would like to debug/trace it.
Since it runs on Heroku. AFAIK I can't insert import pydevd_pycharm; pydevd_pycharm.settrace(... into the code.
I use PyCharm.
But I don't need a fancy GUI. A command-line tool would be fine, too.
I would be happy if I could see all lines which get executed during a particular http request.
How to solve this for production systems?
In order to understand the difference between your local development environment and the Heroku production I would first deploy the application on another Heroku Dyno, for example a Free Dyno which you can easily create and manage.
You can then integrate the tools you want and add the log statements as needed.
Even if you are able to debug/inspect the production runtime it is very important to be able to test on production-like systems to capture problems early and investigate problems without guessing.
On the Prod system you have limited options to debug the application:
consider code changes (i.e. add logging stamements) but as you have pointed out this involves PRs and a new release
debugger: connect your favourite debugger (i.e. PyCharm) to the remote application. This is something that (almost) no one does (given the security aspects and the likely impact on the application performance) and I doubt your system admins/DevOps would agree
I don't know of any tool which can do that, but you shouldn't run into this problem very often. So I wouldn't bother trying to solve this generally, but instead just add logging statements where you think they can be handy to debug this one problem.
I currently work with .NET exclusively and would like to have a go at python. To this end I need to set up a python development environment. I guide to this would be handy. I guess I would be doing web development so will need a web server and probably a database. I also need pointers to popular ORM's, an MVC framework, and a testing library.
One of my main criteria with all this is that I want to understand how it works, and I want it to be as isolated as possible. This is important as i am wary of polluting what is a working .NET environment with 3rd party web and database servers. I am perfectly happy using SQLite to start with if this is possible.
If I get on well with this I am also likely to want to set up automated build and ci server (On a virtual machine, probably ubuntu). Any suggestions for these would be useful.
My ultimate aim if i like python is to have similar sorts of tools that i have available with .NET and to really understand the build and deployment of it all. To start with I will settle for a simple development environment that is as isolated as possible and will be easy to remove if I don't like it. I don't want to use IronPython as I want the full experience of developing a python solution using the tools and frameworks that are generally used.
It's not that hard to set up a Python environment, and I've never had it muck up my .NET work. Basically, install Python --- I'd use 2.6 rather than 3.0, which is not yet broadly accepted --- and add it to your PATH, and you're ready to go with the language. I wouldn't recommend using a Ubuntu VM as your development environment; if you're working on Windows, you might as well develop on Windows, and I've had no significant problems doing so. I go back and forth from Windows to Linux with no trouble.
If you have an editor that you're comfortable with that has basic support for Python, I'd stick with it. If not, I've found Geany to be a nice, light, easy-to-use editor with good Python support, though I use Emacs myself because I know it; other people like SCITE, NotePad++, or any of a slew of others. I'd avoid fancy IDEs for Python, because they don't match the character of the language, and I wouldn't bother with IDLE (included with Python), because it's a royal pain to use.
Suggestions for libraries and frameworks:
Django is the standard web framework, but it's big and you have to work django's way; I prefer CherryPy, which is also actively supported, but is light, gives you great freedom, and contains a nice, solid webserver that can be replaced easily with httpd.
Django includes its own ORM, which is nice enough; there's a standalone one for Python, though, which is even nicer: SQL Alchemy
As far as a testing library goes, pyunit seems to me to be the obvious choice
Good luck, and welcome to a really fun language!
EDIT summary: I originally recommended Karrigell, but can't any more: since the 3.0 release, it's been continuously broken, and the community is not large enough to solve the problems. CherryPy is a good substitute if you like a light, simple framework that doesn't get in your way, so I've changed the above to suggest it instead.
Well, if you're thinking of setting up an Ubuntu VM anyway, you might as well make that your development environment. Then you can install Apache and MySQL or Postgres on that VM just via the standard packaging tools (apt-get install), and there's no danger of polluting your Windows environment.
You can either do the actual development on your Windows machine via your favourite IDE, using the VM as a networked drive and saving the code there, or you can just use the VM as a full desktop environment and do everything there, which is what I would recommend.
Install the pre-configured ActivePython release from activestate.
Among other features, it includes the PythonWin IDE (Windows only) which makes it easy to explore Python interactively.
The recommended reference is Dive Into Python, mentioned many times on similar SO discussions.
You should install python 2.4, python 2.5, python 2.6 and python 3.0, and add to your path the one you use more often (Add c:\Pythonxx\ and c:\Pythonxx\Scripts).
For every python 2.x, install easy_install; Download ez_setup.py and then from the cmd:
c:\Python2x\python.exe x:\path\to\ez_setup.py
c:\Python2x\Scripts\easy_install virtualenv
Then each time you start a new project create a new virtual environment to isolate the specific package you needs for your project:
mkdir <project name>
cd <project name>
c:\Python2x\Scripts\virtualenv --no-site-packages .\v
It creates a copy of python and its libraries in .v\Scripts and .\v\Lib. Every third party packages you install in that environment will be put into .\v\Lib\site-packages. The -no-site-packages don't give access to the global site package, so you can be sure all your dependencies are in .\v\Lib\site-packages.
To activate the virtual environment:
.\v\Scripts\activate
For the frameworks, there are many. Django is great and very well documented but you should probably look at Pylons first for its documentions on unicode, packaging, deployment and testing, and for its better WSGI support.
For the IDE, Python comes with IDLE which is enough for learning, however you might want to look at Eclipse+PyDev, Komodo or Wingware Python IDE. Netbean 6.5 has beta support for python that looks promising (See top 5 python IDE).
For the webserver, you don't need any; Python has its own and all web framework come with their own. You might want to install MySql or ProgreSql; it's often better to develop on the same DB you will use for production.
Also, when you have learnt Python, look at Foundations of Agile Python Development or Expert Python Programming.
Using Python on Windows
SO: Python tutorial for total beginners?
Take a look at Pylons, read about WSGI and Paste.
There's nice introductory Google tech talk about them: ReUsable Web Components with Python and Future Python Web Development.
Here's my answer to similar question:
Django vs other Python web frameworks?
NOTE: I included a lot of links to frameworks, projects and what-not, but as a new user I was limited to 1 link per answer. If someone else with enough reputation to edit wants/can edit them into this answer instead of the footnotes, I'd be grateful.
There are some Python IDE's such as Wing IDE[1], I believe some people use Eclipse[2] with a python plugin[3] as well. A lot of people in the #python channel of FreeNode seem to prefer vim, emacs, nano and similar text editors in favor of IDE's. My personal preffered editor is Vim, but if you've mostly done .NET development on windows, presumably with the usual Visual X IDE's, vim and emacs will probably cause you culture shock and you'd be better of using an IDE.
Nearly all python web frameworks* support the WSGI standard[4], most of the large web servers have some sort of plugin to support WSGI, the others support WSGI via fast cgi or plain cgi.
The Zope[5] and Django[6] frameworks have their own ORM's, of other ORM's the two most well known appear to be SQL Alchemy[7] and SQL Object[8]. I only have experience with the former, but both support all possible sane database choices, including SQLite which is installed together with Python and hence perfectly suited to testing and experimenting without polluting your .NET environment with 3rd part web servers and database servers.
The builtin unittest[9] and pyunit[10] frameworks seem to be the preffered solutions for unit testing, but I don't have much experience with these.
bpython[11] and ipython[12] offer enhanced interactive python shells which can greatly help speed up and testing small bits of code and hence worth looking in to.
As for a list of well known and often used web frameworks, look into the following frameworks**:
Twisted[13] is a generic networking framework, which supports almost every single protocol under the sun.
Pylons[14] is light-weight framework aimed at being as flexible as possible and leaving all the choices about what ORM, templating language and what-not to you.
CherryPy[15] tries to provide an interface to expose Python objects to the web.
Django[6] attempts to be an all-in-one solution, builtin template system, ORM, admin pages and internationalization. While the previous frameworks have more DIY wiring together various frameworks work involved with them.
Zope[5] is aimed to be suitable for large enterprise applications, I've heard nothing but good things about it, but consensus seems to be that for smaller you're probably better off with one of the simpler and smaller frameworks.
TurboGears[16] is the framework I know the least about, but it seems to be mostly competition for Django.
This is everything I can think of right now, I'll edit and add stuff if I can think of it. I hope this helps you some in the wonderful world of python.
* - The main exception would be Apache's mod_python, which you should avoid for exactly that reason, use mod_wsgi instead.
** - Word of warning, I have not personally used these frameworks this is just a very short impression I have gotten from talking to other people about each framework, it may be wildly inaccurate. (If anyone has any corrections, do comment and I'll try to edit and fix this answer).
(The http:// is missing since they're recognized as links otherwise)
[1] www.wingware.com/
[2] www.eclipse.org/
[3] pydev.sourceforge.net/
[4] wsgi.org/wsgi/
[5] www.zope.org/
[6] www.djangoproject.com/
[7] www.sqlalchemy.org/
[8] www.sqlobject.org/
[9] docs.python.org/library/unittest.html
[10] pyunit.sourceforge.net/pyunit.html
[11] www.bpython-interpreter.org/
[12] ipython.scipy.org/
[13] twistedmatrix.com/trac/
[14] pylonshq.com/
[15] www.cherrypy.org/
[16] turbogears.org/
Environment?
Here is the simplest solution:
Install Active Python 2.6. Its the Python itself, but comes with some extra handy useful stuff, like DiveintoPython chm.
Use Komodo Edit 5. It is among the good free editor you can use for Python.
Use IDLE. Its the best simplest short snippet editor, with syntax highlighting and auto complete unmatched by most other IDEs. It comes bundled with python.
Use Ipython. Its a shell that does syntax highlighting and auto complete, bash functions, pretty print, logging, history and many such things.
Install easy_install and/or pip for installing various 3rd party apps easily.
Coming from Visual Studio and .Net it will sound a lot different, but its an entirely different world.
For the framework, django works the best. Walk thro the tutorial and you will be impressed enough. The documentation rocks. The community, you have to see for yourself, to know how wonderful it is!!
Python has build in SQL like database and web server, so you wouldn't need to install any third party apps. Remember Python comes with batteries included.
If you've worked with Eclipse before you could give Pydev a try
Is it possible to run django without shell access? My hoster supports the following for 5€/month:
python (I assume via mod_python)
mysql
There is no shell nor cronjob support, which costs additional 10€/month, so I'm trying to avoid it.
I know that Google Apps also work without shell access, but I assume that is possible because of their special configuration.
It's possible but not desirable. Having shell access makes it possible to centralise things properly using symlinks.
Get a better host would be my first suggestion. WebFaction is the most recommended shared host for using with Django.
If that's out of your price range, there are plenty of hosts that give you a proper system account (vs just a ftp account) and have mod_python or mod_wsgi (preferred now).
Google Apps works without shell because their system looks for a dispatcher script that you have to write to an exact specification.
It is possible.
Usually you will develop your application locally (where shell access is nice to have) and publish your work to your server. All you need for this is FTP access and some way to import a database dump from your development database (often hosters provide an installation of phpMyAdmin for this).
python (I assume via mod_python)
From my experience, you are most certainly wrong with that assumption. Many low-cost providers claim to support python but in fact provide only an outdated version that can be used with CGI scripts. This setup will have a pretty low performance for Django apps.
I'm running Mac OS X Leopard and wanted to know what the easy way to setup a web development environment to use Python, MySQL, Apache on my machine which would allow me to develop on my Mac and then easily move it to a host in the future.
I've been trying to get mod_wsgi installed and configured to work with Django and have a headache now. Are there any web hosts that currently use mod_wsgi besides Google, so I could just develop there?
FWIW, we've found virtualenv [http://pypi.python.org/pypi/virtualenv] to be an invaluable part of our dev setup. We typically work on multiple projects that use different versions of Python libraries etc. It's very difficult to do this on one machine without some way to provide a localized, customized Python environment, as virtualenv does.
Most Python applications are moving away from mod_python. It can vary by framework or provider, but most development effort is going into mod_wsgi.
Using the WSGI standard will make your Python application server agnostic, and allow for other nice additions like WSGI middleware. Other providers may only provide CGI (which won't scale well performance wise), or FastCGI.
I've worked with Django using only the included server in the manager.py script and have not had any trouble moving to a production environment.
If you put your application in a host that does the environment configuration for you (like WebFaction) you should not have problems moving from development to production.
I run a Linux virtual machine on my Mac laptop. This allows me to keep my development environment and production environments perfectly in sync (and make snapshots for easy experimentation / rollback). I've found VMWare Fusion works the best, but there are free open source alternatives such as VirtualBox if you just want to get your feet wet.
I share the source folders from the guest Linux operating system on my Mac and edit them with the Mac source editor of my choosing (I use Eclipse / PyDev because the otherwise excellent TextMate doesn't deal well with Chinese text yet). I've documented the software setup for the guest Linux operating system here; it's optimized for serving multiple Django applications (including geodjango).
For extra added fun, you can edit your Mac's /etc/hosts file to make yourdomainname.com resolve to your guest Linux boxes internal IP address and have a simple way to work on / test multiple web projects online or offline without too much hassle.
What you're looking for is Mod_Python. It's an Apache-based interpreter for Python. Check it out here:
http://www.modpython.org/
Google App Engine has done it for you. Some limitations but it works great, and it gives you a path to hosting free.
Of course Mac OS X, in recent versions, comes with Python and Apache. However you may want to have more flexibility in the versions you use, or you may not like the tweaks Apple has made to the way they are configured. A good way to get a more generic set of tools, including MySQL, is to install them anew. This will help your portability issues. The frameworks can be installed relatively easily with one of these open source package providers.
Fink
MacPorts
MAMP
mod_wsgi is really, really simple.
Pyerweb is a really simple (~90 lines including comments/whitespace) WSGI-compliant routing-framework I wrote. Basically the WSGI API is just a function that gets passed environ, and wsgi_start_response, and it returns a string.
envrion is a dict with the request info, for example environ['PATH_INFO'] is the request URI)
wsgi_start_response which is a callable function which you execute to set the headers,:
wsgi_start_response(output_response, output_headers)
output_response is the string containing the HTTP status you wish to send (200 OK etc), and output_headers is a list-of-tuples containing your headers (for example, [("Content-type", "text/html")] would set the content-type)
Then the function returns a string containing your output.. That's all there is to it!
To run it, using spawning you can just do spawn scriptname.my_wsgi_function_nae and it will start listening on port 8080.
To use it via mod_wsgi, it's documentation is good, http://code.google.com/p/modwsgi/wiki/QuickConfigurationGuide and there is a django specific section
The up-side to using mod_wsgi is it's the standard for serving Python web-applications. I recently decided to play with Google App Engine, and was surprised when Pyerweb (which I linked to at the start of this answer) worked perfectly on it, completely unintentionally. I was even more impressed when I noticed Django applications run on it too.. Standardisation is a good thing!
You may want to look into web2py. It includes an administration interface to develop via your browser. All you need in one package, including Python.
Check out WebFaction—although I don't use them (nor am I related to / profit from their business in any way). I've read over and over how great their service is and particularly how Django-friendly they are. There's a specific post in their forums about getting up and running with Django and mod_wsgi.
Like others before me in this thread, I highly recommend using Ian Bicking's virtualenv to isolate your development environment; there's a dedicated page in the mod_wsgi documentation for exactly that sort of setup.
I'd also urge you to check out pip, which is basically a smarter easy_install which knows about virtualenv. Pip does two really nice things for virtualenv-style development:
Knows how to install from source control (SVN, Git, etc...)
Knows how to "freeze" an existing development environement's requirements so that you can create that environment somewhere else—very very nice for multiple developers or deployment.