# Mongoose Lua Server Pages Pre-built Windows and Mac mongoose binaries support Lua Server Pages functionality. That means it is possible to write PHP-like scripts with mongoose using Lua programming language instead of PHP. Lua is known for it's speed and small size. Mongoose uses Lua version 5.2.3, the documentation for it can be found at [Lua 5.2 reference manual](http://www.lua.org/manual/5.2/). To create a Lua Page, make a file that is called `ANY_NAME.lp`. For example, `my_page.lp`. It is important to have a file name that ends up with `.lp`, cause this is the way mongoose recognises Lua Page file. The contents of the file, just like with PHP, is HTML with embedded Lua code. Lua code must be enclosed within `<? ?>` blocks, and can appear anywhere on the page. Mongoose does not send HTTP headers for Lua pages. Therefore, every Lua Page must begin with HTTP status line and headers, like this: mg.write('HTTP/1.0 200 OK\r\nContent-Type: text/html\r\n\r\n') ?>
Today is: mg.write(os.date("%A")) ?> Note that this example uses function `mg.write()`, which prints data to the web page. Using function `mg.write()` is the way to generate web content from inside Lua code. In addition to `mg.write()`, all standard library functions are accessible from the Lua code (please check reference manual for details). Information about the request is available via the `mg.request_info` object. I contains request method, all headers, etcetera. Please refer to `struct mg_request_info` definition in [mongoose.h](https://github.com/cesanta/mongoose/blob/master/mongoose.h) to see what is available via the `mg.request_info` object. Check out [prime_numbers.lp](https://github.com/cesanta/mongoose/blob/master/examples/lua/prime_numbers.lp) for some example. Mongoose exports the following to the Lua Server Page: mg.write(str) -- writes string to the client mg.onerror(msg) -- error handler, can be overridden mg.request_info -- a table with request information Using Lua scripting it is easy to emulate SSI functionality. For example, to include the content of another file, one can write: mg.write(io.open('MY_FILE.TXT'):read('*all')) ?> To serve a Lua Page, mongoose creates Lua context. That context is used for all Lua blocks within the page. That means, all Lua blocks on the same page share the same context. If one block defines a variable, for example, that variable is visible in all following blocks.