db notifications

base64.lua

#!/usr/bin/env lua
-- Lua 5.1+ base64 v3.0 (c) 2009 by Alex Kloss <[email protected]>
-- licensed under the terms of the LGPL2

-- character table string
local b='ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'

-- encoding
function enc(data)
    return ((data:gsub('.', function(x) 
        local r,b='',x:byte()
        for i=8,1,-1 do r=r..(b%2^i-b%2^(i-1)>0 and '1' or '0') end
        return r;
    end)..'0000'):gsub('%d%d%d?%d?%d?%d?', function(x)
        if (#x < 6) then return '' end
        local c=0
        for i=1,6 do c=c+(x:sub(i,i)=='1' and 2^(6-i) or 0) end
        return b:sub(c+1,c+1)
    end)..({ '', '==', '=' })[#data%3+1])
end

-- decoding
function dec(data)
    data = string.gsub(data, '[^'..b..'=]', '')
    return (data:gsub('.', function(x)
        if (x == '=') then return '' end
        local r,f='',(b:find(x)-1)
        for i=6,1,-1 do r=r..(f%2^i-f%2^(i-1)>0 and '1' or '0') end
        return r;
    end):gsub('%d%d%d?%d?%d?%d?%d?%d?', function(x)
        if (#x ~= 8) then return '' end
        local c=0
        for i=1,8 do c=c+(x:sub(i,i)=='1' and 2^(8-i) or 0) end
        return string.char(c)
    end))
end

-- command line if not called as library
if (arg ~= nil) then
	local func = 'enc'
	for n,v in ipairs(arg) do
		if (n > 0) then
			if (v == "-h") then print "base64.lua [-e] [-d] text/data" break
			elseif (v == "-e") then func = 'enc'
			elseif (v == "-d") then func = 'dec'
			else print(_G[func](v)) end
		end
	end
else
	module('base64',package.seeall)
end

mysql_proxy.lua

-- scratch gist for db modification notifications
function read_query(packet)

    if packet:byte() == proxy.COM_QUERY then

        smtp = require('socket.smtp')

        from = "<[email protected]>"
        rcpt  = {"<[email protected]>"}

        local query = string.sub(packet, 2)
        if string.match(string.upper(query), '^%s*ALTER') then

            local log_query = string.gsub(query, "(\n+)", " ")
            log_query = string.sub(log_query, 0, string.len(log_query))

            mesgt = {
                headers = {
                    to = "<[email protected]>",
                    subject = "Message From Migrations Proxy"
                },
                body = log_query
            }

            smtp.send {
                from = from,
                rcpt = rcpt,
                source = smtp.message(mesgt)
            }

            print(string.sub(log_query, 0, string.len(log_query)))
        end

    end
end