I have just started learning Django and my main aim is to build a company intranet website where I can do system administration things like backups, restore, etc.
I have found various Django tutorials about general web sites, but I could not find any tutorials / links where some have thought about doing system administration things via a web interface.
How can I use models / views and integrate with Python functions?
If all you want is to do administration tasks then I suggest using webmin. If you just want to do this to learn Django/Python then feel free to use the functionality of webmin as a guide. Think about all the steps involved in taking backups, moving files around and other administration tasks. This should help you understand the problem better and break it into manageable chunks.
Remember that Django is really just Python underneath, and it can be a vastly powerful tool. Try looking at some of your Python scripts that you use for systems administration. Maybe you can adapt those as a web interface.
Ansible does what you describe.
As Devin M says, Django is 'just Python' in the backend (that is, the functions your views call), so if you really wanted to, you could use a library like Fabric to invoke system administration actions without needing your web server to have direct access to the infrastructure.
You can use Python (Django) + SSH for doing all the system administration tasks. At my place, we built a web custom computer monitoring system with a system administration capability.
All you need is basically setting up a password-less SSH connection for each server. We chose to use the SSH key method. All system administration tasks were executed using SSH, for example ssh user#server1 'sh backupall.sh'. All that was left was creating a Python (Django) application which executes all these SSH commands.
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I would like to deploy several WSGI web applications with Twisted on a debian server, and need some direction for a solid production setup. These applications will be running 24/7.
I need to run several configurations, each binding to different ports/interfaces/privileges.
I want to do as much of this in python as possible.
I do not want to package my applications with a program like 'tap2deb'.
What is the best way to implement each application as a system service? Do I need some /etc/init.d shell scripts, or can I manage this with python? (I don't want anything quite as heavy as Daemontools)
If I use twistd to manage most of the configuration/process management, what kind of wrappers/supervisors do I need to put in place?
I would like centralized management, but restricting control to the parent user account is not a problem.
The main problem I want to avoid, is having to SSH into my server once a day to restart a blocking/crashed application
I have found several good references for launching daemon processes with python. See daemoncmd from pypi.
Im still coming up a little short on the monitoring/alert solutions (in python).
I am wondering how to go about implementing a web application with Python.
For example, the html pages would link to python code that would give it increased functionality and allow it to write to a database.
Kind of like how Reddit does it.
If you're looking for server side programming with databases and html templates etc, I think Django is great, along with Pyramid. However, I use Flask ( http://flask.pocoo.org/ ) for this since it is easy to use, learn and deploy even though it may not have as much support as the before mentioned 2 framework since it's just a microframework, using the Jinja2 templating engine, including a development test server with it's own debugger.
On the other hand, if you're going for client-side programming (i.e. in browser implementation ) You can look up .NET Ironpython or even Brython which uses python like javascript.
You might want to check out mod_wsgi or mod_python.
What Is mod_wsgi?
The aim of mod_wsgi is to implement a simple to use
Apache module which can host any Python application which supports the
Python WSGI interface. The module would be suitable for use in hosting
high performance production web sites, as well as your average self
managed personal sites running on web hosting services.
-
Current State of Mod_Python
Currently mod_python is not under active development. This does not
mean that it is "dead" as some people have claimed. It smiply means
that the code and the project are mature enough when very little is
required to maintain it.
This is a good article from the Python website:
http://docs.python.org/howto/webservers.html
Plain CGI is a good starting point to learn about server side scripting, but it is an outdated technology and gets difficult to maintain after certain level of complexity. I would think it is no longer used in industrial-grade web server anymore. Plus you have to setup a web server and then install some module to interpret python script (like Apache with mod_python) just to get started.
I had some experience with Django (https://www.djangoproject.com/) and found it fairly easy to get started with since they come with development test server. All you need to have is a Python interpreter + Django and you can get up-and-running quickly and worry about the deployment setup later. They have pretty good documentation for beginner as well.
We have never used Python for a web site without a framework. In our case that is Django. In other words, we do not use Python for our web sites the way Perl can be used, just having Apache run a Perl script.
The recommendations you have received about Django are sound. If you go the Django route, Graham Dumpleton and the modwsgi Google group were very helpful to me. I could
not have gotten mod_wsgi deployed on Red Hat Enterprise 5 64-bit without Graham's help.
Whether you choose Django or "straight" Python, you will need to become familiar with mod_wsgi.
Good luck in quantum time, which means by now, I hope this all worked out for you.
I need to develop a web application with the following requirements:
Desktop like UI on the client side
Application deployment
Scalability (i.e. distributing the service on multiple servers)
What I thought of so far (as I love Python but haven't done much web development yet):
Django
Fabric (think I've read somewhere it's suited for this)
What I'm missing is:
How to create rich clients (probably need some javascript libraries for that)?
How to distribute the service?
For RIA you need to use some client technology in your templates.
See at Dojo or ExtJs.
ExtJs docs have example of Web Desktop app, but this library is not free for commercial project. I like more Dojo, and it is free.
Rich Internet Application: Javascript to do stuff asynchronously (AJAX). If you want a desktop-like interface on the web, it seems currently CoffeeScript is the way to go. It's a language that compiles into Javascript and adapted for rich interfaces.
Deployment: fabric (I think it's used to deploy Python apps).
Distribution: you deploy the code to one server.If you need to scale it up, you just need some additional servers (of course if you have specific usages like very high load on a database, you'll also need to add more database servers etc. But you get the idea).
using web browser as your client platform?
Is there any lightweight mvc webframework which is not necessary to install to the server?
I need something simple, that i could just copy to the shared hosting. And it must handle urls other that localhost/test.py, something like this localhost/Blog/test
You should probably check out Flask or Bottle, two nice Python microframeworks. With an appropriate "main" Python script (to initialize your app and dispatch requests to it) and mod_rewrite rules in place, you can probably get pretty close to your goal of "just copy[ing] to the shared hosting" with nice URLs.
Flask has good documentation on deploying via CGI, which is what you might have to use on your shared host. (If your host supports FastCGI or mod_wsgi, those deployment options would be preferable.)
Checkout web2py. Seems to be about the simplest python based webserver I can think of.
Django might do, it's hefty, but it comes with it's own development server.
web2py includes everything (ssl-enabled web server, sqlite sql based transaction safe database, web based Integrated Development Enviroment, web based database interface) in one package. The web2py binaries for windows and mac also include Python itself. web2py does not require configuration or installation and can run off a usb drive. It was originally developed as a teaching tool for MVC.
checkout https://github.com/salimane/bottle-mvc or https://github.com/salimane/flask-mvc . They are boilerplates that could get you started with controllers, models in separate folders. They are based on bottle and flask micro frameworks, no useless features, they give you the flexibility to plugin whatever modules you want.
I have a Django application that I would like to deploy to the desktop. I have read a little on this and see that one way is to use freeze. I have used this with varying success in the past for Python applications, but am not convinced it is the best approach for a Django application.
My questions are: what are some successful methods you have used for deploying Django applications? Is there a de facto standard method? Have you hit any dead ends? I need a cross platform solution.
I did this a couple years ago for a Django app running as a local daemon. It was launched by Twisted and wrapped by py2app for Mac and py2exe for Windows. There was both a browser as well as an Air front-end hitting it. It worked pretty well for the most part but I didn't get to deploy it out in the wild because the larger project got postponed. It's been a while and I'm a bit rusty on the details, but here are a few tips:
IIRC, the most problematic thing was Python loading C extensions. I had an Intel assembler module written with C "asm" commands that I needed to load to get low-level system data. That took a while to get working across both platforms. If you can, try to avoid C extensions.
You'll definitely need an installer. Most likely the app will end up running in the background, so you'll need to mark it as a Windows service, Unix daemon, or Mac launchd application.
In your installer you'll want to provide a way to locate a free local TCP port. You may have to write a little stub routine that the installer runs or use the installer's built-in scripting facility to find a port that hasn't been taken and save it to a config file. You then load the config file inside your settings.py and whatever front-end you're going to deploy. That's the shared port. Or you could just pick a random number and hope no other service on the desktop steps on your toes :-)
If your front-end and back-end are separate apps then you'll need to design an API for them to talk to each other. Make sure you provide a flag to return the data in both raw and human-readable form. It really helps in debugging.
If you want Django to be able to send notifications to the user, you'll want to integrate with something like Growl or get Python for Windows extensions so you can bring up toaster pop-up notifications.
You'll probably want to stick with SQLite for database in which case you'll want to make sure you use semaphores to tackle multiple requests vying for the database (or any other shared resource). If your app is accessed via a browser users can have multiple windows open and hit the app at the same time. If using a custom front-end (native, Air, etc...) then you can control how many instances are running at a given time so it won't be as much of an issue.
You'll also want some sort of access to local system logging facilities since the app will be running in the background and make sure you trap all your exceptions and route it into the syslog. A big hassle was debugging Windows service startup issues. It would have been impossible without system logging.
Be careful about hardcoded paths if you want to stay cross-platform. You may have to rely on the installer to write a config file entry with the actual installation path which you'll have to load up at startup.
Test actual deployment especially across a variety of firewalls. Some of the desktop firewalls get pretty aggressive about blocking access to network services that accept incoming requests.
That's all I can think of. Hope it helps.
If you want a good solution, you should give up on making it cross platform. Your code should all be portable, but your deployment - almost by definition - needs to be platform-specific.
I would recommend using py2exe on Windows, py2app on MacOS X, and building deb packages for Ubuntu with a .desktop file in the right place in the package for an entry to show up in the user's menu. Unfortunately for the last option there's no convenient 'py2deb' or 'py2xdg', but it's pretty easy to make the relevant text file by hand.
And of course, I'd recommend bundling in Twisted as your web server for making the application easily self-contained :).