使用ngx_lua模块(http://wiki.nginx.org/HttpLuaModule)：

local request_method = ngx.var.request_method

local args = nil

local param = nil

local param2 = nil

--获取参数的值

if "GET" == request_method then

args = ngx.req.get_uri_args()

elseif "POST" == request_method then

ngx.req.read_body()

args = ngx.req.get_post_args()

end

param = args["param"]

param2 = args["param2"]

升级版(能处理content-type=multipart/form-data的表单)：

local function explode ( _str,seperator )

local pos, arr = 0, {}

for st, sp in function() return string.find( _str, seperator, pos, true ) end do

table.insert( arr, string.sub( _str, pos, st-1 ) )

pos = sp + 1

end

table.insert( arr, string.sub( _str, pos ) )

return arr

end

local args = {}

local file_args = {}

local is_have_file_param = false

local function init_form_args()

local receive_headers = ngx.req.get_headers()

local request_method = ngx.var.request_method

if "GET" == request_method then

args = ngx.req.get_uri_args()

elseif "POST" == request_method then

ngx.req.read_body()

if string.sub(receive_headers["content-type"],1,20) == "multipart/form-data;" then--判断是否是multipart/form-data类型的表单

is_have_file_param = true

content_type = receive_headers["content-type"]

body_data = ngx.req.get_body_data()--body_data可是符合http协议的请求体，不是普通的字符串

--请求体的size大于nginx配置里的client_body_buffer_size，则会导致请求体被缓冲到磁盘临时文件里，client_body_buffer_size默认是8k或者16k

if not body_data then

local datafile = ngx.req.get_body_file()

if not datafile then

error_code = 1

error_msg = "no request body found"

else

local fh, err = io.open(datafile, "r")

if not fh then

error_code = 2

error_msg = "failed to open " .. tostring(datafile) .. "for reading: " .. tostring(err)

else

fh:seek("set")

body_data = fh:read("*a")

fh:close()

if body_data == "" then

error_code = 3

error_msg = "request body is empty"

end

end

end

end

local new_body_data = {}

--确保取到请求体的数据

if not error_code then

local boundary = "--" .. string.sub(receive_headers["content-type"],31)

local body_data_table = explode(tostring(body_data),boundary)

local first_string = table.remove(body_data_table,1)

local last_string = table.remove(body_data_table)

for i,v in ipairs(body_data_table) do

local start_pos,end_pos,capture,capture2 = string.find(v,'Content%-Disposition: form%-data; name="(.+)"; filename="(.*)"')

if not start_pos then--普通参数

local t = explode(v,"rnrn")

local temp_param_name = string.sub(t[1],41,-2)

local temp_param_value = string.sub(t[2],1,-3)

args[temp_param_name] = temp_param_value

else--文件类型的参数，capture是参数名称，capture2是文件名

file_args[capture] = capture2

table.insert(new_body_data,v)

end

end

table.insert(new_body_data,1,first_string)

table.insert(new_body_data,last_string)

--去掉app_key,app_secret等几个参数，把业务级别的参数传给内部的API

body_data = table.concat(new_body_data,boundary)--body_data可是符合http协议的请求体，不是普通的字符串

end

else

args = ngx.req.get_post_args()

end

end

end