在此先把前面自己做的那个功能在此分享下，是一个模仿淘宝的，希望大神们有什么想法可以不吝赐教：

自己是通过前面的参考配置lua与nginx的结合使用，利用脚本语言lua的强大特性和nginx的特性来实现这个功能，在nginx.conf的配置文件中加入如下代码：

server { listen 22222; server_name localhost; # server_name somename alias another.alias; location /images/{ alias /root/images; set $image_root /root; set $file $image_root$uri; content_by_lua ' ngx.header.content_type = "text/plain"; ngx.say(ngx.var.file); '; } location /lua{ set $test "hello, world."; content_by_lua ' ngx.header.content_type = "text/plain"; ngx.say(ngx.var.test); '; } location /group1/M00 { alias /usr/local/servers/data/fdfs/data; set $image_root "/usr/local/servers/data/fdfs/data"; # alias /root/images; # set $image_root "/root/images"; if ( $uri ~ "/([a-zA-Z0-9]+)/([a-zA-Z0-9]+)/([a-zA-Z0-9]+)/([a-zA-Z0-9]+)/(.*)" ) { set $image_dir "$image_root/$3/$4"; set $image_name "$5"; set $file "$image_dir/$image_name"; } # content_by_lua ' # ngx.header.content_type = "text/plain"; # ngx.say(ngx.var.image_dir); # ngx.say(ngx.var.image_name); # ngx.say(ngx.var.file); # '; if ( !-f $file ) { # 关闭lua代码缓存，方便调试lua脚本 #lua_code_cache off; content_by_lua_file "/usr/local/servers/lua/convert.lua"; } ngx_fastdfs_module; } # location ~ /group[1-3]/M00{ # root /usr/local/servers/data/fdfs/data; #/fdfs/storage/data; # ngx_fastdfs_module; # } }

这里面利用了nginx的正则表达式，正则表达式是相当强悍的，可以得到你需要访问的uri的值。

然后再convert.lua中写入如下代码：

local area = nillocal originalUri = ngx.var.uri;local originalFile = ngx.var.file;local index = string.find(ngx.var.uri, "([0-9]+)x([0-9]+)");if index then originalUri = string.sub(ngx.var.uri, 0, index-2); area = string.sub(ngx.var.uri, index); index1 = string.find(area, "([.])"); area1 = string.sub(area, 0, index1-1); local index2 = string.find(originalFile, "([0-9]+)x([0-9]+)"); originalFile1 = string.sub(originalFile, 0, index2-2)endlocal image_sizes = {"80x80", "800x600", "40x40", "60x60"};function table.contains(table, element) for _, value in pairs(table) do if value == element then return true end end return falseendif table.contains(image_sizes, area1) then local command = "/usr/bin/gm convert " .. originalFile1 .. " -thumbnail " .. area1 .. " -background gray -gravity center -extent " .. area1 .. " " .. ngx.var.file; os.execute(command);end;

~差不多这样就可以实现功能了，通过访问可以实现比率压缩，因为在上班时间暂时就这么写下了，目前的一个工作还有很多功能需要实现，如有看不懂的可以留言，大神们可以指教，谢谢！

参考：http:///t/113845

http://blog.sina.com.cn/openresty

http://write.blog.csdn.net/postedit

https://github.com/azurewang/lua-resty-fastdfs/blob/master/lib/resty/fastdfs/storage.lua

https:///sys/CentOS/55070.htm

http://wiki.nginx.org/HttpLuaModule