Lua 风格的 Nginx 重写或内部重定向循环

Question

我对nginx和都很陌生lua。我正在尝试按照本教程进行操作http://leafo.net/posts/creating_an_image_server.html#installation_requirements但我无论如何也无法获得这个nginx.conf权利。

我检查过其他类似的问题这问题出在哪里location，但我看不出我的代码有什么问题。

这里是nginx.conf：

error_log stderr notice;
daemon off;

events { }

http {
  include /usr/local/openresty/nginx/conf/mime.types;

  server {
    listen 6789;
    lua_code_cache on;

    location @image_server {
      content_by_lua_file "serve_image.lua";
    }

    location ~ ^/images/(?<size>[^/]+)/(?<path>.*\.(?<ext>[a-z_]*))$ {
      root cache;
      try_files /$path @image_server;
    }

  }
}

这是serve_image.lua代码

local sig, size, path, ext =

ngx.var.sig、ngx.var.size、ngx.var.path、ngx.var.ext local images_dir = "images/" -- 图片来源 local cache_dir = "cache/" -- 图片缓存位置

local function return_not_found(msg)
  ngx.status = ngx.HTTP_NOT_FOUND
  ngx.header["Content-type"] = "text/html"
  ngx.say(msg or "not found")
  ngx.exit(0)
end

local source_fname = images_dir .. path
ngx.log(ngx.STDERR, "->>>>  " .. source_fname)

-- make sure the file exists
local file = io.open(source_fname)

if not file then
  ngx.log(ngx.STDERR, "Couldn't find the input file" .. source_fname)
  return_not_found()
end

file:close()

local dest_fname = cache_dir .. "/" .. size .. "/" .. path

-- resize the image
local magick = require("magick")
magick.thumb(source_fname, size, dest_fname)

ngx.exec(ngx.var.request_uri)

当我运行服务器时，我得到代码 500。

这是终端中的错误

rewrite or internal redirection cycle while redirect to named location "@image_server", client: 127.0.0.1, server: , request: "GET /images/80x80/wow.png HTTP/1.1", host: "localhost:6789"

我希望更有经验、更新颖的人能指出我做错的地方。谢谢。