OpenResty lua_shared_dict (缓存)

ゝ一世哀愁。 2022-10-11 13:34 291阅读 0赞

# 1 案例 #

## 1.1 get\_value.lua ##

**描述：** 从redis中获取value

local redis = require "redis_conf"
    local red = redis:new()
    
    
    function get_from_redis(key)
        local res,err=red:get(key)
        if res then
            return res
        else
            return err
        end
    end
    
    local value=get_from_redis('value')
    ngx.say("value: ", value)

## 1.2 nginx.conf ##

http { 
        include       mime.types;
        default_type  application/octet-stream;
        
        sendfile        on;
      
        keepalive_timeout  65;
        
        lua_package_path  "/usr/local/openresty/nginx/lua/conf/?.lua;;";
        
        server { 
            listen       80;
            server_name  localhost;
            
           lua_code_cache on;
           
           location / { 
                root   html;
                index  index.html index.htm;
           }    
           
           location /get_value { 
               default_type 'text/html';
               content_by_lua_file  lua/get_value.lua;
           }   
           
        }
        
    }

## 1.3 ab测试 ##

#重启
    /usr/local/openresty/nginx/sbin/nginx  -c /usr/local/openresty/nginx/conf/nginx.conf  -s reload
    #测试10W并发 100客户端
    ab -n 100000 -c 100  -k http://192.168.38.38/get_value

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM0MTI1OTk5_size_16_color_FFFFFF_t_70]

# 2 加入lua\_shared\_dict #

## 2.1 nginx.conf ##

lua_shared_dict cache_ngx 128m;

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM0MTI1OTk5_size_16_color_FFFFFF_t_70 1]

## 2.2 get\_value.lua ##

local redis = require "redis_conf"
    local red = redis:new()
    
    -- 从redis中获取
    function get_from_redis(key)
        local res, err = red:get(key)
        if res then
            return res
        else
            return err
        end
    end
    
    
    -- 设置nginx 缓存数据
    function set_to_cache(key, value, expire)
        if not expire then
            expire = 0
        end
    
        local cache_ngx = ngx.shared.cache_ngx
        local succ, err, forcible  = cache_ngx:set(key, value, expire)
        return succ
    end
    
    
    -- 从nginx缓存中获取
    function get_from_cache(key)
    
        local cache_ngx = ngx.shared.cache_ngx
        local value = cache_ngx:get(key)
    
        if not value then
            value = get_from_redis(key)
            set_to_cache(key, value)
        end
    
        return value
    end
    
    local value = get_from_cache('value')
    
    ngx.say("value: ", value)

## 2.3 ab 测试 ##

#重启
    ab -n 100000 -c 100  -k http://192.168.38.38/get_value

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM0MTI1OTk5_size_16_color_FFFFFF_t_70 2]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM0MTI1OTk5_size_16_color_FFFFFF_t_70]: /images/20221005/c593dee721ae4e66a29e43b9bca7f17c.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM0MTI1OTk5_size_16_color_FFFFFF_t_70 1]: /images/20221005/f231b5f68a5a42a2a8fe6c8922704fcd.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM0MTI1OTk5_size_16_color_FFFFFF_t_70 2]: /images/20221005/9cf7809b779b45b49770c19868d0c003.png