worker_processes  1;        #nginx worker 數量
error_log logs/error.log;   #指定錯誤紀錄檔檔案路徑
events {
    worker_connections 1024;
}

http {
    log_format main '$remote_addr [$time_local] $status $request_time $upstream_status $upstream_addr $upstream_response_time';
    access_log logs/access.log main buffer=16384 flush=3;            #access_log 檔案設定

    lua_package_path  "${prefix}deps/share/lua/5.1/?.lua;${prefix}deps/share/lua/5.1/?/init.lua;${prefix}?.lua;${prefix}?/init.lua;;./?.lua;/usr/local/openresty/luajit/share/luajit-2.1.0-beta3/?.lua;/usr/local/share/lua/5.1/?.lua;/usr/local/share/lua/5.1/?/init.lua;/usr/local/openresty/luajit/share/lua/5.1/?.lua;/usr/local/openresty/luajit/share/lua/5.1/?/init.lua;";
    lua_package_cpath "${prefix}deps/lib64/lua/5.1/?.so;${prefix}deps/lib/lua/5.1/?.so;;./?.so;/usr/local/lib/lua/5.1/?.so;/usr/local/openresty/luajit/lib/lua/5.1/?.so;/usr/local/lib/lua/5.1/loadall.so;";
    # 開啟 lua code 快取
    lua_code_cache on;

    upstream nature_upstream {
        server 127.0.0.1:6699; #upstream 設定為 hello world 服務

        # 一樣的balancer
        balancer_by_lua_block {
            local balancer = require "ngx.balancer"
            local upstream = ngx.ctx.api_ctx.upstream
            local ok, err = balancer.set_current_peer(upstream.host, upstream.port)
            if not ok then
                ngx.log(ngx.ERR, "failed to set the current peer: ", err)
                return ngx.exit(ngx.ERROR)
            end
        }
    }

    # 換為init_worker 是因為 init 不允許請求etcd
    init_worker_by_lua_block {

        node = nil
        -- 匹配路由， 為了演示，這裡簡化為單個節點，並且路由處理也去掉了
        router_match = function()
            return node
        end

        -- 從etcd 載入設定，同理為了演示簡單，這裡只做單個節點
        local etcdlib = require("resty.etcd").new({
            protocol = "v3",
            api_prefix = "/v3",
            http_host = 'http://127.0.0.1:2479',
            key_prefix = '/test/'
        })

        -- 這裡為了簡單，展示輪詢方式， watch 的方式可以參考 https://github.com/fs7744/nature/blob/main/nature/config/etcd.lua
        ngx.timer.every(1, function()
            local res, err = etcdlib:get('node')
            local json = require('cjson.safe')
            
            if res ~= nil and res.body ~= nil and res.body.kvs ~= nil and res.body.kvs[1] ~= nil then
                node = res.body.kvs[1].value
                ngx.log(ngx.ERR, json.encode(node))
            end
        end)
    }

    server {
		#監聽埠，若你的8699埠已經被佔用，則需要修改
        listen 8699 reuseport;

        location / {

            # 在access階段匹配路由
            access_by_lua_block {
                local upstream = router_match()
                if upstream then
                    ngx.ctx.api_ctx = { upstream = upstream }
                else
                    ngx.exit(404)
                end
            }

            proxy_http_version                  1.1;
            proxy_pass http://nature_upstream; #轉發到 upstream
        }
    }


    #為了大家方便理解和測試，我們引入一個hello world 服務
    server {
		#監聽埠，若你的6699埠已經被佔用，則需要修改
        listen 6699;
        location / {
            default_type text/html;

            content_by_lua_block {
                ngx.say("HelloWorld")
            }
        }
    }
}