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--[[ $%BEGINLICENSE%$
Copyright (C) 2007-2008 MySQL AB, 2008 Sun Microsystems, Inc
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
$%ENDLICENSE%$ --]]
--[[
--]]
-- init the query-counter if it isn't done yet
if not proxy.global.query_counter then
proxy.global.query_counter = 0
end
local query_counter = 0
---
-- read_query() can return a resultset
--
-- You can use read_query() to return a result-set.
--
-- @param packet the mysql-packet sent by the client
--
-- @return
-- * nothing to pass on the packet as is,
-- * proxy.PROXY_SEND_QUERY to send the queries from the proxy.queries queue
-- * proxy.PROXY_SEND_RESULT to send your own result-set
--
function read_query( packet )
-- a new query came in in this connection
proxy.global.query_counter = proxy.global.query_counter + 1
query_counter = query_counter + 1
if string.byte(packet) == proxy.COM_QUERY then
--[[
we use a simple string-match to split commands are word-boundaries
mysql> show querycounter
is split into
command = "show"
option = "querycounter"
spaces are ignored, the case has to be as is.
mysql> show myerror
returns a error-packet
--]]
-- try to match the string up to the first non-alphanum
local f_s, f_e, command = string.find(packet, "^%s*(%w+)", 2)
local option
if f_e then
-- if that match, take the next sub-string as option
f_s, f_e, option = string.find(packet, "^%s+(%w+)", f_e + 1)
end
-- we got our commands, execute it
if string.lower(command) == "show" and string.lower(option) == "querycounter" then
---
-- proxy.PROXY_SEND_RESULT requires
--
-- proxy.response.type to be either
-- * proxy.MYSQLD_PACKET_OK or
-- * proxy.MYSQLD_PACKET_ERR
--
-- for proxy.MYSQLD_PACKET_OK you need a resultset
-- * fields
-- * rows
--
-- for proxy.MYSQLD_PACKET_ERR
-- * errmsg
proxy.response.type = proxy.MYSQLD_PACKET_OK
proxy.response.resultset = {
fields = {
{ type = proxy.MYSQL_TYPE_LONG, name = "global_query_counter", },
{ type = proxy.MYSQL_TYPE_LONG, name = "query_counter", },
},
rows = {
{ proxy.global.query_counter, query_counter }
}
}
-- we have our result, send it back
return proxy.PROXY_SEND_RESULT
elseif string.lower(command) == "show" and string.lower(option) == "myerror" then
proxy.response.type = proxy.MYSQLD_PACKET_ERR
proxy.response.errmsg = "my first error"
return proxy.PROXY_SEND_RESULT
end
end
end
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