From 1abcc5045f292c44ea45b898c2f6b384dc74907e Mon Sep 17 00:00:00 2001
From: JaguarJack <njphper@gmail.com>
Date: Thu, 2 Jul 2020 18:41:47 +0800
Subject: [PATCH] =?UTF-8?q?=E6=96=B0=E5=A2=9E=E4=BB=A4=E7=89=8C=E6=A1=B6?=
 =?UTF-8?q?=E9=99=90=E6=B5=81?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 extend/catcher/library/rate/RateLimiter.php | 177 ++++++++++++++++++++
 1 file changed, 177 insertions(+)
 create mode 100644 extend/catcher/library/rate/RateLimiter.php

diff --git a/extend/catcher/library/rate/RateLimiter.php b/extend/catcher/library/rate/RateLimiter.php
new file mode 100644
index 0000000..758ffc0
--- /dev/null
+++ b/extend/catcher/library/rate/RateLimiter.php
@@ -0,0 +1,177 @@
+<?php
+// +----------------------------------------------------------------------
+// | CatchAdmin [Just Like ～ ]
+// +----------------------------------------------------------------------
+// | Copyright (c) 2017~2020 http://catchadmin.com All rights reserved.
+// +----------------------------------------------------------------------
+// | Licensed ( https://github.com/yanwenwu/catch-admin/blob/master/LICENSE.txt )
+// +----------------------------------------------------------------------
+// | Author: JaguarJack [ njphper@gmail.com ]
+// +----------------------------------------------------------------------
+namespace catcher\library\rate;
+
+use catcher\exceptions\FailedException;
+
+class RateLimiter
+{
+    use Redis;
+
+    protected $key;
+
+    /**
+     * 令牌容量
+     *
+     * @var int
+     */
+    protected $capacity = 5;
+
+    /**
+     * 每次添加 token 的数量
+     *
+     * @var int
+     */
+    protected $eachTokens = 5;
+
+    /**
+     * 添加 token 的时间
+     *
+     * @var string
+     */
+    protected $addTokenTimeKey = '_add_token';
+
+    /**
+     * 添加 token 的时间间隔 /s
+     *
+     * @var int
+     */
+    protected $interval = 5;
+
+    /**
+     * RateLimiter constructor.
+     * @param $key
+     */
+    public function __construct($key)
+    {
+        $this->key = $key;
+    }
+
+    /**
+     * 处理
+     *
+     * @time 2020年07月02日
+     * @return void
+     */
+    public function overflow()
+    {
+        // 添加 token
+        if ($this->canAddToken()) {
+            $this->addTokens();
+        }
+
+        if (!$this->tokens()) {
+            throw new FailedException('访问限制');
+        }
+
+        // 每次请求拿走一个 token
+        $this->removeToken();
+    }
+
+    /**
+     *
+     *
+     * @time 2020年07月02日
+d     * @return void
+     */
+    protected function addTokens()
+    {
+        $leftTokens = $this->capacity - $this->tokens();
+
+        $tokens = array_fill(0, $leftTokens < $this->eachTokens ? $leftTokens : $this->eachTokens, 1);
+
+        $this->getRedis()->lPush($this->key, ...$tokens);
+
+        $this->rememberAddTokenTime();
+    }
+
+    /**
+     * 拿走一个 token
+     *
+     * @time 2020年07月02日
+     * @return void
+     */
+    protected function removeToken()
+    {
+        $this->getRedis()->rPop($this->key);
+    }
+
+    /**
+     * 设置令牌桶数量
+     *
+     * @time 2020年07月02日
+     * @param $capacity
+     * @return $this
+     */
+    public function setCapacity($capacity)
+    {
+        $this->capacity = $capacity;
+
+        return $this;
+    }
+
+    /**
+     * 剩余的 token 数量
+     *
+     * @time 2020年07月02日
+     * @return bool|int
+     */
+    protected function tokens()
+    {
+        return $this->getRedis()->lLen($this->key);
+    }
+
+
+    /**
+     * 设置时间间隔
+     *
+     * @time 2020年07月02日
+     * @param $seconds
+     * @return $this
+     */
+    public function setInterval($seconds)
+    {
+        $this->interval = $seconds;
+
+        return $this;
+    }
+
+    /**
+     * 是否可以添加 token
+     *
+     * @time 2020年07月02日
+     * @return bool
+     */
+    protected function canAddToken()
+    {
+        $currentTime = \time();
+
+        $lastAddTokenTime = $this->getRedis()->get($this->key. $this->addTokenTimeKey);
+
+        // 如果是满的 则不添加
+        if ($this->tokens() == $this->capacity) {
+            return false;
+        }
+
+        return ($currentTime - $lastAddTokenTime) > $this->interval;
+    }
+
+    /**
+     * 记录添加 token 的时间
+     *
+     * @time 2020年07月02日
+     * @return void
+     */
+    protected function rememberAddTokenTime()
+    {
+        $this->getRedis()->set($this->key. $this->addTokenTimeKey, time());
+    }
+}
\ No newline at end of file