Lua is a very useful language for many things.  Extending core base code with modules and add-ons have made it very useful in game development but since Lua is table-based it can also be easily applied to web development. Well that time has come, See the Kepler Project for a nice collection of modules that make a good start for web development with Lua.

Kepler is an open source platform that brings the power of Lua to web development. There are a number of great Web development platforms out there but none balances portability, size, power and extensibility quite like Kepler does:

• Being extremely portable and light means that it can be installed in very constrained devices as much as in providers that limit the amount of RAM and processing time for your scripts.
• If you ever heard of the customization features of games such as World of Warcraft, think about all that power applied to web scripting.
• Being extensible means both that we can extend the platform by adding new modules and that the users of the applications that you build can extend those applications using Lua.

Kepler was created by Fábrica Digital and PUC-Rio and is continuously being improved by a core team of commiters (see Dev Team) and lots of contributors (see Credits).

Kepler is free software and uses the MIT license model: it can be used for both academic and commercial purposes at absolutely no cost. See the Kepler License for more details.

Kepler is a platform that uses LuaRocks to offer Modules such as:

• Page based and MVC XHTML generation (WSAPI, CGILua and Orbit)
• SQL and XML processing (LuaSQL and LuaExpat)
• Hash (MD5) and a pair crypt/decrypt
• Zip files reading (LuaZip)

The Lua community is constantly contributing with more modules that can be used with the Kepler Architecture. Most of those modules are catalogued on LuaForge and new ones keep coming.

Unix installation

Please check UNIX Installation for a detailed view of how to install Kepler on Unix machines (including OSX).

Windows installation

Installing Kepler on Windows does not require any C compiler and should work on any Windows machine with internet access.

1. Download LuaRocks and install it using install /SCRIPTS c:\luarocks\0.5.2
2. Add the LuaRocks scripts dir to your system path (the same directory used in the /SCRIPTS parameter above)
3. Install Kepler and Xavante using luarocks install kepler-xavante
4. Configure everything using setup-kepler and following the instructions
5. Use xavante to run Xavante as a tray bar application, or use ‘xavante_start’ to run Xavante from the command prompt. Another option is to run Kepler using CGI

Once Kepler is running, you might want to look at those pages:

• Hello World will tell you how to write a simple application
• Using a Database will tell you how to use some of the popular databases with Kepler.
• Configuring Web Servers will tell you how to use Kepler with some specific web servers.

The Kepler 1.1 Unix installer can be downloaded from its downloads page. Check the Installation page for more details and for the Windows installation instructions (using LuaRocks).

If you need the binaries for specifics Modules you can also get them from LuaForge, on the module respective project page.

Finally rest for all that boilerplate in Java.  At each turn of lots of Java frameworks you are bombarded with layers.  I felt this long ago and see it in the developers eyes that work with Java.  Java can be easy, it can be RESTful and it will make you look sharp.

Lightweight REST framework for Java

Do you want to embrace the architecture of the Web and benefit from its simplicity and scalability? Leverage our innovative REST engine and start blending your Web Sites and Web Services into uniform Web Applications!

Java is making things more lightweight now with lots of emerging kits that compete with other web ready platforms like Python, Ruby, .NET, PHP etc. After this many years things get bloated and need to be simplified.  I think this will start winning people over in this direction.

If you have ever worked on a massively high trafficked website, you know that cache is very important to keeping the server count down and being a superhero to your database servers. Cache can be bad and overly optimized but when you hit a certain threshold, relational databases, databases that are dimension modelled for data warehouse, and even server resources get exhausted. At that point you have two options, buy more servers, or more likely, cache read data.

Each platform has their own way to do this, but there is a common baseplane way to do caching, yes even in .NET. That is with memcached. Memcached is a very common and useful tool that makes caching data and cache layers in an application something that can be the same on every platform. The benefit of using memcached is it is open, common and it has APIs for nearly every popular web development platform (and can be wired in easily to platforms that don’t have their own cache mechanism). Why write your caching layer specific to a certain platform when you can memcache?

If you write high performance web apps and don’t memcache, I feel bad for your server budget and your late nights when that ad buy hits or something popular on your site becomes all the rave.

Perl API

An object-oriented Perl module can be found on CPAN as Cache::Memcached or in Subversion (ChangeLog). (GPL/Artistic)

The Perl API takes advantage of the server’s opaque flag support and sets its “complex” flag whenever the object being stored or retrieved isn’t a plain scalar. In that case, the Storable module is used to freeze and thaw the value automatically going in and out of the memcached.

There is also Cache::Memcached::Fast—another Perl client written in C, largely compatible with the original Cache::Memcached. Available on CPAN at http://search.cpan.org/dist/Cache-Memcached-Fast/.

PHP API

There are tons of PHP libraries available, in different conditions. But it now seems there’s an official one:

• PHP PECL memcached client — official PHP client

Python API

The Python client we’d previously released was just a prototype, and we don’t have regular Python programmers on hand. The folks at Tummy.com have took over maintenance. See ftp://ftp.tummy.com/pub/python-memcached/ for the latest versions.

Ruby API

• http://www.deveiate.org/code/Ruby-MemCache.html
• gem install memcache-client
• http://blog.evanweaver.com/files/doc/fauna/memcached/. C backed client wrapping libmemcached.

Java API

A Java API is maintained by Greg Whalin from Meetup.com. You can find that library here:

• http://www.whalin.com/memcached/ — Java API for memcached

An improved Java API maintained by Dustin Sallings is also available. Aggressively optimised, ability to run async, supports binary protocol, etc. See site for details:

• http://bleu.west.spy.net/~dustin/projects/memcached/ — Improved Java API for memcached

C# API

There are multiple C# APIs:

• https://sourceforge.net/projects/memcacheddotnet/
• http://www.codeplex.com/EnyimMemcached/ - Client developed in .NET 2.0 keeping performance and extensibility in mind. (Supports consistent hashing.)
• http://code.google.com/p/beitmemcached/ - Client developed by BeIT with many new features.

C API

Multiple C libraries for memcached exist:

• apr_memcache by Paul Querna; Apache Software License version 2.0
• libmemcached by Brian Aker; BSD license. This is a new library, under heavy development.
• libmemcache by Sean Chittenden; BSD license. This is the original C library. It is no longer under active development. You should try libmemcached instead.

Postgres API

The pgmemcache project allows you to access memcache servers from Postgresql Stored Procedures and Triggers. More details and downloads are available at:

• http://pgfoundry.org/projects/pgmemcache/

Chicken Scheme

• http://chicken.wiki.br/memcached — Chicken Scheme library

Lua

• http://luamemcached.luaforge.net/ — Lua library

MySQL API

The memcache_engine allows memcache to work as a storage engine to MySQL. This means that you can SELECT/UPDATE/INSERTE/DELETE from it as though it is a table in MySQL.

• memcache_engine

A set of MySQL UDFs (user defined functions) to work with memcached using libmemcached.

• MySQL UDFs for memcached

Protocol

To write a new client, check out the protocol docs. Be aware that the most important part of the client is the hashing across multiple servers, based on the key, or an optional caller-provided hashing value. Feel free to join the mailing list (or mail me directly) for help, inclusion in Subversion, and/or a link to your client from this site.

The best part, they support all good platforms and even Lua, and wisely they left out VB.NET, no worries, VB.NET’ers will never know. Only kidding…

Finally, memcached is distributed, most cache layers included with platforms listed above are in process and per machine.  If you are running your code on a webfarm memcached is the only way to go.

Yes you can Export a clean build with TortoiseSVN so that you have a clean copy without the .svn tracking items, remove the directory and make a new one.

But, if you need to clean up an existing folder you can use some old skool bat/cmd in the root with this command on Windows

for /f "tokens=* delims=" %%i in ('dir /s /b /a:d *svn') do ( rd /s /q "%%i" )

[source]

Just put that in a .cmd file like cleansvn.cmd like the source suggests in the root of the subversion project you want to clean up. Works nicely. It essentially just uses the rd command to remove directories recursively that match ’svn’.

I will be featuring tutorials and utilities with subversion including some tools to quickly add and pull the newly imported trees into Subversion that can be cumbersome. I will also be doing some in an IronPython command scripting language that gives you the full power of the .net language runtime to use in your scripts.

Bringing scripts back to Windows through good uses is the goal. Scripts are not always good to build on but for quick common tasks they can be great ways to do tasks much quicker.

For *nix you can just do

find . -type d -name ‘.svn' -print0 | xargs -0 rm -rdf