nginx lua log request and response

使用lua模块可以进行request和reponse的记录。
以下摘自：serverfault.com
worker_processes 1;
error_log logs/error.log;
events {

worker_connections 1024;

}
http {

log_format log_req_resp '$remote_addr - $remote_user [$time_local] '
    '"$request" $status $body_bytes_sent '
    '"$http_referer" "$http_user_agent" $request_time req_body:"$request_body" resp_body:"$resp_body"';

server {
    listen 8082;
    access_log logs/access.log log_req_resp;

    lua_need_request_body on;

    set $resp_body "";
    body_filter_by_lua '
        local resp_body = string.sub(ngx.arg[1], 1, 1000)
        ngx.ctx.buffered = (ngx.ctx.buffered or "") .. resp_body
        if ngx.arg[2] then
            ngx.var.resp_body = ngx.ctx.buffered
        end
    ';

    location / {
        echo "Hello World!";
    }
}

}