nginx+lua+redis实现限流的示例代码

# 安装wget 如果没有的话
yum install wget
# 下载资源库 这样yum就可以直接安装了
# 得到 openresty.repo
cd /etc/yum.repos.d/
wget https://openresty.org/package/centos/openresty.repo
# 安装openresty 安装目录:/usr/local/openresty
yum install openresty

cd /usr/local/openresty/nginx/conf
vim nginx-lua.conf

content_by_lua_block {
	ngx.say("hello");
	ngx.say("block");
}

# nginx-lua.conf
worker_processes 1;
error_log logs/error.log debug;
events {
	worker_connections 1024;
}

http {
	include mime.types;
	default_type application/octet-stream;
	sendfile on;
	# 连接的超时时间
	keepalive_timeout 65;
	server {
		listen 8080;
		location / {
			default_type text/html;
			# 此处可以写lua脚本的文件路径
			content_by_lua_file /usr/local/openresty/nginx/lua/ip_limit_log.lua;
		}
	}
}

-- ip_limit_access.lua
ngx.say("ip limit lua");

# 查看nginx是否启动
ps -ef | grep nginx
# 停止nginx
/usr/local/openresty/nginx/sbin/nginx -s stop
# 启动nginx  -p指定工作目录  -c 指定配置文件
/usr/local/openresty/nginx/sbin/nginx -p /usr/local/openresty/nginx/ -c /usr/local/openresty/nginx/conf/nginx-lua.conf
# 使用curl访问地址 测试成功
[root@localhost nginx]# curl http://localhost
ip limit lua

# ngin-ip-limit.conf
worker_processes 1;
error_log logs/error.log debug;
events {
	worker_connections 1024;
}
http {
	include mime.types;
	default_type application/octet-stream;
	server {
		listen 80;
		localtion / {
			default_type text/html;
			# 配置lua脚本文件路径
			access_by_lua_file /usr/local/openresty/nginx/lua/ip_limit_access.lua;
			# 配置lua日志脚本路径
			log_by_lua_file /usr/local/openresty/nginx/lua/ip_limit_log.lua;
			# 需要准备一个被代理的服务
			proxy_pass http://localhost:8080/;
		}
	}
}

-- ip_limit_log.lua
local ip = ngx.var.remote_addr;
ngx.log(ngx.INFO, "request ip is:"..ip);

-- ip_limit_access.lua
ngx.log(ngx.INFO, "ip limit log");

local redis = require "resty.redis";
local red = redis:new();

-- 连接redis
red:connect("127.0.0.1",6379);

-- 判断是否限流
limit = red:get("limit");
if limit == '1' then
  return ngx.exit(503);
end
-- 次数加1
inc = red:incr("testLimit");
if inc <= 2 then
  -- 设置过期时间 1秒
  red:expire("testLimit",1);
else
  -- 超过阈值 limit设置成1 并设置过期时间10秒
  red:set("limit",1);
  red:expire("limit", 10);
end