php 结合lua和redis保护API(令牌桶算法)

# 命令来查看可用版本
docker search redis
# 拉取官方的最新版本的镜像
docker pull redis:latest
# 查看是否已安装了 redis
docker images
#运行redis容器
#–-requirepass 设置密码
#–-appendonly 开启redis 持久化
docker run -itd --name myredis -p 6379:6379 redis  --requirepass "123456"  --appendonly yes
#查看容器的运行
docker ps 

<?php

$http = new Swoole\Http\Server('0.0.0.0', 8080);
$http->on('Request', function ($request, $response) {
  if ($request->server['path_info'] == '/favicon.ico' || $request->server['request_uri'] == '/favicon.ico') {
      $response->end();
      return;
  }
  $lua = file_get_contents('limiter.lua');
  $redis = new Redis();
  $redis->connect('192.168.56.2');
  $redis->auth(123456);
  $key = 'lingpai';
  if (isset($request->get['method'])) {
      //初始化令牌
      $message = '初始化令牌失败！';
      if ($redis->eval($lua,[$key, 'initTokenBucket',100, 1],1)) {
          $message = '初始化令牌成功！';
      }
      $response->end($message);
      return;
  }
  //请求时间
  $curr_mill_second = $redis->eval($lua,['currentTimeMillis'],0);
  //获取令牌
  $result = $redis->eval($lua,[$key, 'acquire',1, $curr_mill_second],1);
  $response->end($result);
});
$http->start();

# 命令行执行开启服务
php test.php 

--- @param key 令牌的唯一标识
--- @param permits  请求令牌数量
--- @param curr_mill_second 当前时间
--- 0 没有令牌桶配置；-1 表示取令牌失败，也就是桶里没有令牌；1 表示取令牌成功
local function acquire(key,  permits, curr_mill_second)
    local local_key =  key --- 令牌桶key ,使用 .. 进行字符串连接
    if tonumber(redis.pcall("EXISTS", local_key)) < 1 then --- 未配置令牌桶
        return 0
    end

    --- 令牌桶内数据：
    ---             last_mill_second  最后一次放入令牌时间
    ---             curr_permits  当前桶内令牌
    ---             max_permits   桶内令牌最大数量
    ---             rate  令牌放置速度
    local rate_limit_info = redis.pcall("HMGET", local_key, "last_mill_second", "curr_permits", "max_permits", "rate")
    local last_mill_second = rate_limit_info[1]
    local curr_permits = tonumber(rate_limit_info[2])
    local max_permits = tonumber(rate_limit_info[3])
    local rate = rate_limit_info[4]

    --- 标识没有配置令牌桶
    if type(max_permits) == 'boolean' or max_permits == nil then
        return 0
    end
    --- 若令牌桶参数没有配置，则返回0
    if type(rate) == 'boolean' or rate == nil then
        return 0
    end

    local local_curr_permits = max_permits;

    --- 令牌桶刚刚创建，上一次获取令牌的毫秒数为空
    --- 根据和上一次向桶里添加令牌的时间和当前时间差，触发式往桶里添加令牌，并且更新上一次向桶里添加令牌的时间
    --- 如果向桶里添加的令牌数不足一个，则不更新上一次向桶里添加令牌的时间
    --- ~=号在Lua脚本的含义就是不等于!=
    if (type(last_mill_second) ~= 'boolean'  and last_mill_second ~= nil) then
        if(curr_mill_second - last_mill_second < 0) then
            return -1
        end
        --- 生成令牌操作
        local reverse_permits = math.floor(((curr_mill_second - last_mill_second) / 1000) * rate) --- 最关键代码：根据时间差计算令牌数量并匀速的放入令牌
        local expect_curr_permits = reverse_permits + curr_permits;
        local_curr_permits = math.min(expect_curr_permits, max_permits);  --- 如果期望令牌数大于桶容量，则设为桶容量
    --- 大于0表示这段时间产生令牌，则更新最新令牌放入时间
        if (reverse_permits > 0) then
            redis.pcall("HSET", local_key, "last_mill_second", curr_mill_second)
        end
    else
        redis.pcall("HSET", local_key, "last_mill_second", curr_mill_second)
    end
    --- 取出令牌操作
    local result = -1
    if (local_curr_permits - permits >= 0) then
        result = 1
        redis.pcall("HSET", local_key, "curr_permits", local_curr_permits - permits)
    else
        redis.pcall("HSET", local_key, "curr_permits", local_curr_permits)
    end
    return result
end

--- 初始化令牌桶
--- @param key 令牌的唯一标识
--- @param max_permits最大令牌数
--- param rate令牌放置速度
local function initTokenBucket(key, max_permits, rate)
    if(key == nil or string.len(key) < 1) then
        return 0
    end
    local local_max_permits = 100
    if(tonumber(max_permits) > 0) then
        local_max_permits = max_permits
    end

    local local_rate = 100
    if(tonumber(rate) > 0) then
        local_rate = rate
    end
    redis.pcall("HMSET", key, "max_permits", local_max_permits, "rate", local_rate)
    return 1;
end

--- 获取当前时间，单节点获取，避免集群模式下(无论业务系统集群，还是redis集群)获取的时间不同，导致桶不匀速
local function currentTimeMillis()
    local times = redis.pcall("TIME")
    return tonumber(times[1]) * 1000 + tonumber(times[2]) / 1000
end



--- key，即redis中的key。
local key = KEYS[1]
--- args第一个参数即要调用的方法名。
local method = ARGV[1]
--- 请求令牌
if method == 'acquire' then
    return acquire(key, ARGV[2], ARGV[3])
    --- 请求时间
elseif method == 'currentTimeMillis' then
    return currentTimeMillis()
    --- 初始化令牌桶
elseif method == 'initTokenBucket' then
    return initTokenBucket(key, ARGV[2], ARGV[3])
end

<?php

while (true) {
    $redis = new Redis();
    $redis->connect('192.168.56.2');
    $redis->auth(123456);
    $data = $redis->hMget('lingpai',['max_permits','curr_permits','rate']);
    echo "最大的令牌数：{$data['max_permits']}---------每秒生成令牌数:{$data['rate']}----------当前令牌数：{$data['curr_permits']}\r\n";
    sleep(3);
}

# 命令行执行
php check.php

http://192.168.56.2:8080/?method #初始化令牌成功！

http://192.168.56.2:8080/   #返回1则获取到令牌 返回-1则获取失败