Faster Web Applications with SCGI
Once you're comfortable writing programs using SCGI, you may want to try adapting existing applications to use it. Some well-known Web applications, such as MoinMoin (a wiki) and Trac (a wiki-based collaborative development environment), are implemented as Python modules. Both of these examples come with CGI scripts in Python that can be called from Apache. The CGI scripts are very short; they really don't do anything except import the application's modules and invoke a function on them.
If you find an application like that, all you really need to do to make it work with SCGI is take that little bit of Python code and move it into a produce() method, as in the examples you've seen here. If you have SCGI 1.12 or newer, you also might want to take a look at an alternative SCGIHandler method, produce_cgilike().
That's about all we have room for. If you wonder about how the CGI parameters work, try looking at the CGI standard, which calls them “request meta-variables” (see Resources).
Finally, a word of warning. You'll notice that the last example program dies horribly if you fail to pass the expected arguments. The SCGI server replaces the failing processes, so in this case, there's no real problem. But, this should remind you how careful you need to be when writing Web applications. Never trust the input you receive from outside! If a program can be crashed, someone can probably subvert it or take it out of action. People all over the world do that sort of thing for fun or profit, so take the risk seriously.
SCGI Downloads: quixote.python.ca/releases
SCGI Home Page: www.mems-exchange.org/software/scgi
CGI Standard: ftp.rfc-editor.org/in-notes/rfc3875.txt
More on SCGI with Python and Apache2: thaiopensource.org/development/suriyan/wiki/UsingScgi
Perl Interface: search.cpan.org/~vipercode/SCGI/lib/SCGI.pm
Lisp Interface: randallsquared.com/download/scgi
Jeroen Vermeulen works for the Open Source Department of the Thai Software Industry Promotion Agency. He's currently working on Suriyan, a server system for those who don't have time for server systems.
|Speed Up Your Web Site with Varnish||Jun 19, 2013|
|Non-Linux FOSS: libnotify, OS X Style||Jun 18, 2013|
|Containers—Not Virtual Machines—Are the Future Cloud||Jun 17, 2013|
|Lock-Free Multi-Producer Multi-Consumer Queue on Ring Buffer||Jun 12, 2013|
|Weechat, Irssi's Little Brother||Jun 11, 2013|
|One Tail Just Isn't Enough||Jun 07, 2013|
- Speed Up Your Web Site with Varnish
- Containers—Not Virtual Machines—Are the Future Cloud
- Linux Systems Administrator
- Lock-Free Multi-Producer Multi-Consumer Queue on Ring Buffer
- Non-Linux FOSS: libnotify, OS X Style
- Senior Perl Developer
- Technical Support Rep
- UX Designer
- RSS Feeds
- Reply to comment | Linux Journal
3 hours 49 min ago
- Yeah, user namespaces are
5 hours 6 min ago
- Cari Uang
8 hours 37 min ago
- user namespaces
11 hours 31 min ago
11 hours 56 min ago
- One advantage with VMs
14 hours 25 min ago
- about info
14 hours 58 min ago
14 hours 59 min ago
15 hours 32 sec ago
15 hours 2 min ago
Free Webinar: Hadoop
How to Build an Optimal Hadoop Cluster to Store and Maintain Unlimited Amounts of Data Using Microservers
Realizing the promise of Apache® Hadoop® requires the effective deployment of compute, memory, storage and networking to achieve optimal results. With its flexibility and multitude of options, it is easy to over or under provision the server infrastructure, resulting in poor performance and high TCO. Join us for an in depth, technical discussion with industry experts from leading Hadoop and server companies who will provide insights into the key considerations for designing and deploying an optimal Hadoop cluster.
Some of key questions to be discussed are:
- What is the “typical” Hadoop cluster and what should be installed on the different machine types?
- Why should you consider the typical workload patterns when making your hardware decisions?
- Are all microservers created equal for Hadoop deployments?
- How do I plan for expansion if I require more compute, memory, storage or networking?