LuaSqlite.md 2.47 KB
Newer Older
Sergey Lyubka's avatar
Sergey Lyubka committed
1 2
# Mongoose Lua Server Pages

Sergey Lyubka's avatar
Sergey Lyubka committed
3 4 5
Pre-built Windows and Mac mongoose binaries support Lua Server Pages
functionality.
That means it is possible to write PHP-like scripts with mongoose
Sergey Lyubka's avatar
Sergey Lyubka committed
6
using Lua programming language instead of PHP. Lua is known
Sergey Lyubka's avatar
Sergey Lyubka committed
7
for it's speed and small size. Mongoose uses Lua version 5.2.3, the
Sergey Lyubka's avatar
Sergey Lyubka committed
8 9 10
documentation for it can be found at
[Lua 5.2 reference manual](http://www.lua.org/manual/5.2/).

Sergey Lyubka's avatar
Sergey Lyubka committed
11 12
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
Sergey Lyubka's avatar
Sergey Lyubka committed
13 14 15
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
Sergey Lyubka's avatar
Sergey Lyubka committed
16
`<?  ?>` blocks, and can appear anywhere on the page.
Sergey Lyubka's avatar
Sergey Lyubka committed
17

Sergey Lyubka's avatar
Sergey Lyubka committed
18 19 20 21 22 23 24
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') ?>
    <html><body>
      <span>Today is:</span> <? mg.write(os.date("%A")) ?>
    </body></html>
Sergey Lyubka's avatar
Sergey Lyubka committed
25 26 27 28

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
Sergey Lyubka's avatar
Sergey Lyubka committed
29
are accessible from the Lua code (please check reference manual for details).
Sergey Lyubka's avatar
Sergey Lyubka committed
30
Information about the request is available via the `mg.request_info` object.
Sergey Lyubka's avatar
Sergey Lyubka committed
31
I contains request method, all headers, etcetera. Please refer to
Sergey Lyubka's avatar
Sergey Lyubka committed
32 33
`struct mg_request_info` definition in
[mongoose.h](https://github.com/cesanta/mongoose/blob/master/mongoose.h)
Sergey Lyubka's avatar
Sergey Lyubka committed
34 35
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.
Sergey Lyubka's avatar
Sergey Lyubka committed
36

Sergey Lyubka's avatar
Sergey Lyubka committed
37
Mongoose exports the following to the Lua Server Page:
Sergey Lyubka's avatar
Sergey Lyubka committed
38 39 40 41 42

    mg.write(str)     -- writes string to the client
    mg.onerror(msg)   -- error handler, can be overridden
    mg.request_info   -- a table with request information

Sergey Lyubka's avatar
Sergey Lyubka committed
43 44
Using Lua scripting it is easy to emulate SSI functionality. For example,
to include the content of another file, one can write:
Sergey Lyubka's avatar
Sergey Lyubka committed
45

Sergey Lyubka's avatar
Sergey Lyubka committed
46
    <? mg.write(io.open('MY_FILE.TXT'):read('*all')) ?>
Sergey Lyubka's avatar
Sergey Lyubka committed
47

Sergey Lyubka's avatar
Sergey Lyubka committed
48
To serve a Lua Page, mongoose creates Lua context. That context is used for
Sergey Lyubka's avatar
Sergey Lyubka committed
49 50
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
Sergey Lyubka's avatar
Sergey Lyubka committed
51
variable is visible in all following blocks.