FWIW, while less known in the West, Taobao.com is one of the world's most highest-trafficked websites. It's the eBay equivalent in China and has many more use cases, such as buying plane tickets or new clothes.
After a bit of testing I am starting some more serious Nginx+Lua development.
The big advantage is that it is a pretty mature http stack that is tested in production at scale, unlike some of the newer frameworks (that you probably run behind nginx anyway). It still has some limitations like the proxy module only supports http 1.0 and some of the chunked encoding stuff is partial at this point, but it is generally sufficient.
Luajit is really fast and nice to use (the ffi interface can call C directly) and coroutines mean that blocking calls can just drop back to the event loop. You have to write anything blocking as an nginx module though, hence this collection of modules as a bundle.
Having a real programming language in the context of a web server is nice, you can either do small things like write complex auth that you might otherwise have a proxy for, or you can write full content handlers.
Agentzh is pretty helpful on the nginx list with issues too.
Perl is just the the built process of the bundle. Lua is the programming language inside Nginx.
Tir looks nice too. It is more targeted at websocket type applications, although it is general purpose too. Nginx supports more traditional HTTP models, I dont know of any native websocket support for it, but you can of course use it to proxy to mongrel/node or whatever. Nginx has the maturity advantage, and you can use it as a proxy, load balancer, and so on. With the Lua support and these additional modules that taobao developed you get a full environment all in one place.
For those unfamiliar with the Nginx/Lua setup, here's the introduction:
"Lua-nginx-module integrated Lua into NginX, and providing high-concurrent & non-blocking request processing ability without forcing developers explicitly dividing business logics into state machine. Developers can write their programs in plain-old sequential ways, and lua-nginx-module will automatically interrupt the program logic at blockable I/O operations, save the context and delegate these I/O ops to NginX’s event mechanism. When I/O ops are done, lua-nginx-module will restore the context and restore the normal running of the program logic. User program itself will feel everything as usual as never being interrupted.
Lua-nginx-module use one-coroutine-per-request request handling model, i.e. for each incoming request, lua-nginx-module spawns a coroutine to run user code to process the request, and the coroutine is destroyed when request handling process is done. Every coroutine has its own independent global environment, which inherits shared read-only common data. So any globals injected by user code won’t affect other request’s processing, and will be freed when request handling is done. You can imagine that user code is running in a ‘sandbox’, which shares the same lifecycle with request itself. By this way, lua-nginx-module can prevent memory-leak caused by the abusing of globals in user code, and improved service robustness.
Benefit from Lua’s excellant coroutine support, lua-nginx-module can handle tens of thousands of concurrent requests with very low memory overhead. According to our tests, the memory overhead for each request in lua-nginx-module is only 2 KB or even half smaller if LuaJIT is used. So obviously lua-nginx-module is a good candidate for implementing extensive concurrent services."
Be able to write in sequential logic flow and have the underlying language+system automatically turning it into async calls is a huge win. This is like having the async benefit of Node.js without dealing with all the callbacks.
taobao.com use php on their front page, so I guess this is used for web services internally and/or used for new developments.
The blog of the main developer[1] is quite interesting, too.
I'm going to have a serious look at it. I've always liked lua (something between tcl and python, language-wise), and even if it doesn't make the cut as a front end solution (because of missing stuff or simply because I'm going with a pure javascript frontend), it would seem to be a good replacement for a non-blocking backend server like node.js.
I think a Ngnix/Lua full stack web app environment is a great idea. (In fact, I think there's a comment of mine with this very idea from about 8 months back.)
