🐜 Update random sequence resolve to use real random (#37)

* 🐜 Update random sequence resolve to use real random

* fix spelling errors

* Update readme documentation

* 😠 update test coverage

Author: godruoyi

README-zh_CN.md

@@ -1,23 +1,23 @@
 <div>
   <p align="center">
-    <image src="https://www.pngkey.com/png/full/105-1052235_snowflake-png-transparent-background-snowflake-with-clear-background.png" width="250" height="250">
+    <image src="https://www.pngkey.com/png/full/105-1052235_snowflake-png-transparent-background-snowflake-with-clear-background.png" width="250" height="250"></image>
   </p>
   <p align="center">An ID Generator for PHP based on Snowflake Algorithm (Twitter announced).</p>
   <p align="center">
     <a href="https://github.com/godruoyi/php-snowflake/actions/workflows/php.yml">
-      <image src="https://github.com/godruoyi/php-snowflake/actions/workflows/php.yml/badge.svg" alt="build passed">
+      <image src="https://github.com/godruoyi/php-snowflake/actions/workflows/php.yml/badge.svg" alt="build passed"></image>
     </a>
     <a href="https://codecov.io/gh/godruoyi/php-snowflake">
       <img src="https://codecov.io/gh/godruoyi/php-snowflake/branch/master/graph/badge.svg?token=7AAOYCJK97"/>
     </a>
     <a href="https://github.com/godruoyi/php-snowflake">
-      <image src="https://poser.pugx.org/godruoyi/php-snowflake/license" alt="License">
+      <image src="https://poser.pugx.org/godruoyi/php-snowflake/license" alt="License"></image>
     </a>
     <a href="https://packagist.org/packages/godruoyi/php-snowflake">
-      <image src="https://poser.pugx.org/godruoyi/php-snowflake/v/stable" alt="Packagist Version">
+      <image src="https://poser.pugx.org/godruoyi/php-snowflake/v/stable" alt="Packagist Version"></image>
     </a>
     <a href="https://github.com/godruoyi/php-snowflake">
-      <image src="https://poser.pugx.org/godruoyi/php-snowflake/downloads" alt="Total Downloads">
+      <image src="https://poser.pugx.org/godruoyi/php-snowflake/downloads" alt="Total Downloads"></image>
     </a>
   </p>
 </div>
@@ -49,7 +49,8 @@ Snowflake 是 Twitter 内部的一个 ID 生算法，可以通过一些简单的
 * LaravelSequenceResolver（基于 redis psetex 和 incrby 生成）
 * SwooleSequenceResolver（基于 swoole_lock 锁）
 
-不同的提供者只需要保证**同一毫秒生成的序列号不同**，就能得到唯一的 ID。
+> **Warning**
+> RandomSequenceResolver 序列号提供者在高并发情况下可能会导致生成的 ID 重复，如果你的应用场景中可能会出现高并发的情况，建议使用 RedisSequenceResolver 或者 LaravelSequenceResolver。
 
 ## 要求
 
@@ -111,15 +112,14 @@ class AppServiceProvider extends ServiceProvider
      */
     public function register()
     {
-        $this->app->singleton('snowflake', function () {
+        $this->app->singleton('snowflake', function ($app) {
             return (new Snowflake())
-                ->setStartTimeStamp(strtotime('2019-08-08')*1000)
-                ->setSequenceResolver(
-                    new LaravelSequenceResolver($this->app->get('cache')->store()
-                ));
+                ->setStartTimeStamp(strtotime('2019-10-10')*1000)
+                ->setSequenceResolver(new LaravelSequenceResolver($app->get('cache.store')));
         });
     }
 }
+}
 ```
 
 2. 自定义序列号解决器

README.md

@@ -1,23 +1,23 @@
 <div>
   <p align="center">
-    <image src="https://www.pngkey.com/png/full/105-1052235_snowflake-png-transparent-background-snowflake-with-clear-background.png" width="250" height="250" />
+    <image src="https://www.pngkey.com/png/full/105-1052235_snowflake-png-transparent-background-snowflake-with-clear-background.png" width="250" height="250"></image>
   </p>
   <p align="center">An ID Generator for PHP based on Snowflake Algorithm (Twitter announced).</p>
   <p align="center">
     <a href="https://github.com/godruoyi/php-snowflake/actions/workflows/php.yml">
-      <image src="https://github.com/godruoyi/php-snowflake/actions/workflows/php.yml/badge.svg" alt="build passed" />
+      <image src="https://github.com/godruoyi/php-snowflake/actions/workflows/php.yml/badge.svg" alt="build passed"></image>
     </a>
     <a href="https://codecov.io/gh/godruoyi/php-snowflake">
-      <img src="https://codecov.io/gh/godruoyi/php-snowflake/branch/master/graph/badge.svg?token=7AAOYCJK97"/>
+      <img src="https://codecov.io/gh/godruoyi/php-snowflake/branch/master/graph/badge.svg?token=7AAOYCJK97" alt=""/>
     </a>
     <a href="https://github.com/godruoyi/php-snowflake">
-      <image src="https://poser.pugx.org/godruoyi/php-snowflake/license" alt="License" />
+      <image src="https://poser.pugx.org/godruoyi/php-snowflake/license" alt="License"></image>
     </a>
     <a href="https://packagist.org/packages/godruoyi/php-snowflake">
-      <image src="https://poser.pugx.org/godruoyi/php-snowflake/v/stable" alt="Packagist Version" />
+      <image src="https://poser.pugx.org/godruoyi/php-snowflake/v/stable" alt="Packagist Version"></image>
     </a>
     <a href="https://github.com/godruoyi/php-snowflake">
-      <image src="https://poser.pugx.org/godruoyi/php-snowflake/downloads" alt="Total Downloads" />
+      <image src="https://poser.pugx.org/godruoyi/php-snowflake/downloads" alt="Total Downloads"></image>
     </a>
   </p>
 </div>
@@ -40,7 +40,7 @@ Snowflake is a network service for generating unique ID numbers at high scale wi
 > You must know, The ID generated by the snowflake algorithm is not guaranteed to be unique.
 > For example, when two different requests enter the same node of the same data center at the same time, and the sequence generated by the node is the same, the generated ID will be duplicated.
 
-So if you want use the snowflake algorithm to generate unique ID, You must ensure: The sequence-number generated in the same millisecond of the same node is unique.
+So if you want to use the snowflake algorithm to generate unique ID, You must ensure: The sequence-number generated in the same millisecond of the same node is unique.
 Based on this, we created this package and integrated multiple sequence-number providers into it.
 
 * RandomSequenceResolver (Random)
@@ -55,7 +55,7 @@ Each provider only needs to ensure that the serial number generated in the same
 
 ## Requirement
 
-1. PHP >= 7.0
+1. PHP >= 7.2
 2. **[Composer](https://getcomposer.org/)**
 
 ## Installation
@@ -87,7 +87,7 @@ $snowflake->id();
 
 ```php
 $snowflake = new \Godruoyi\Snowflake\Snowflake;
-$snowflake->setStartTimeStamp(strtotime('2019-09-09')*1000);
+$snowflake->setStartTimeStamp(strtotime('2019-09-09')*1000); // millisecond
 
 $snowflake->id();
 ```
@@ -113,10 +113,10 @@ class AppServiceProvider extends ServiceProvider
      */
     public function register()
     {
-        $this->app->singleton('snowflake', function () {
+        $this->app->singleton('snowflake', function ($app) {
             return (new Snowflake())
                 ->setStartTimeStamp(strtotime('2019-10-10')*1000)
-                ->setSequenceResolver(new LaravelSequenceResolver($this->app->get('cache')->store()));
+                ->setSequenceResolver(new LaravelSequenceResolver($app->get('cache.store')));
         });
     }
 }
@@ -132,7 +132,7 @@ class YourSequence implements SequenceResolver
     /**
      *  {@inheritdoc}
      */
-    public function sequence(int $currentTime)
+    public function sequence(int $currentMillisecond)
     {
           // Just test.
         return mt_rand(0, 1);
@@ -149,17 +149,17 @@ And you can use closure:
 
 ```php
 $snowflake = new \Godruoyi\Snowflake\Snowflake;
-$snowflake->setSequenceResolver(function ($currentTime) {
+$snowflake->setSequenceResolver(function ($currentMillisecond) {
     static $lastTime;
     static $sequence;
 
-    if ($lastTime == $currentTime) {
+    if ($lastTime == $currentMillisecond) {
         ++$sequence;
     } else {
         $sequence = 0;
     }
 
-    $lastTime = $currentTime;
+    $lastTime = $currentMillisecond;
 
     return $sequence;
 })->id();

src/LaravelSequenceResolver.php

@@ -17,7 +17,7 @@ class LaravelSequenceResolver implements SequenceResolver
     /**
      * The laravel cache instance.
      *
-     * @var \Illuminate\Contracts\Cache\Repository
+     * @var Repository
      */
     protected $cache;
 

src/RandomSequenceResolver.php

@@ -13,7 +13,7 @@
 class RandomSequenceResolver implements SequenceResolver
 {
     /**
-     * The las ttimestamp.
+     * The last timestamp.
      *
      * @var null
      */
@@ -26,21 +26,36 @@ class RandomSequenceResolver implements SequenceResolver
      */
     protected $sequence = 0;
 
+    /**
+     * Max sequence number in one ms.
+     *
+     * @var int
+     */
+    protected $maxSequence = Snowflake::MAX_SEQUENCE_SIZE;
+
     /**
      *  {@inheritdoc}
      */
     public function sequence(int $currentTime)
     {
         if ($this->lastTimeStamp === $currentTime) {
-            ++$this->sequence;
+            $this->sequence++;
             $this->lastTimeStamp = $currentTime;
 
             return $this->sequence;
         }
 
-        $this->sequence = 0;
+        $this->sequence = mt_rand(0, $this->maxSequence);
         $this->lastTimeStamp = $currentTime;
 
         return 0;
     }
+
+    /**
+     * @param  int  $maxSequence
+     */
+    public function setMaxSequence(int $maxSequence): void
+    {
+        $this->maxSequence = $maxSequence;
+    }
 }

src/RedisSequenceResolver.php

@@ -18,7 +18,7 @@ class RedisSequenceResolver implements SequenceResolver
     /**
      * The redis client instance.
      *
-     * @var \Redis
+     * @var Redis
      */
     protected $redis;
 
@@ -61,7 +61,7 @@ public function sequence(int $currentTime)
     }
 
     /**
-     * Set cacge prefix.
+     * Set cache prefix.
      */
     public function setCachePrefix(string $prefix)
     {

src/Snowflake.php

@@ -10,6 +10,8 @@
 
 namespace Godruoyi\Snowflake;
 
+use Exception;
+
 class Snowflake
 {
     public const MAX_TIMESTAMP_LENGTH = 41;
@@ -20,6 +22,8 @@ class Snowflake
 
     public const MAX_SEQUENCE_LENGTH = 12;
 
+    public const MAX_SEQUENCE_SIZE = (-1 ^ (-1 << self::MAX_SEQUENCE_LENGTH));
+
     public const MAX_FIRST_LENGTH = 1;
 
     /**
@@ -39,7 +43,7 @@ class Snowflake
     /**
      * The Sequence Resolver instance.
      *
-     * @var null|\Godruoyi\Snowflake\SequenceResolver
+     * @var null|SequenceResolver
      */
     protected $sequence;
 
@@ -53,15 +57,15 @@ class Snowflake
     /**
      * Default sequence resolver.
      *
-     * @var null|\Godruoyi\Snowflake\SequenceResolver
+     * @var null|SequenceResolver
      */
     protected $defaultSequenceResolver;
 
     /**
      * Build Snowflake Instance.
      *
-     * @param int $datacenter
-     * @param int $workerid
+     * @param  int|null  $datacenter
+     * @param  int|null  $workerid
      */
     public function __construct(int $datacenter = null, int $workerid = null)
     {
@@ -127,22 +131,24 @@ public function getCurrentMicrotime()
 
     /**
      * Set start time (millisecond).
+     *
+     * @throws Exception
      */
-    public function setStartTimeStamp(int $startTime)
+    public function setStartTimeStamp(int $millisecond)
     {
-        $missTime = $this->getCurrentMicrotime() - $startTime;
+        $missTime = $this->getCurrentMicrotime() - $millisecond;
 
         if ($missTime < 0) {
-            throw new \Exception('The start time cannot be greater than the current time');
+            throw new Exception('The start time cannot be greater than the current time');
         }
 
         $maxTimeDiff = -1 ^ (-1 << self::MAX_TIMESTAMP_LENGTH);
 
         if ($missTime > $maxTimeDiff) {
-            throw new \Exception(sprintf('The current microtime - starttime is not allowed to exceed -1 ^ (-1 << %d), You can reset the start time to fix this', self::MAX_TIMESTAMP_LENGTH));
+            throw new Exception(sprintf('The current microtime - starttime is not allowed to exceed -1 ^ (-1 << %d), You can reset the start time to fix this', self::MAX_TIMESTAMP_LENGTH));
         }
 
-        $this->startTime = $startTime;
+        $this->startTime = $millisecond;
 
         return $this;
     }
@@ -154,7 +160,7 @@ public function setStartTimeStamp(int $startTime)
      */
     public function getStartTimeStamp()
     {
-        if ($this->startTime > 0) {
+        if (! is_null($this->startTime)) {
             return $this->startTime;
         }
 
@@ -167,7 +173,7 @@ public function getStartTimeStamp()
     /**
      * Set Sequence Resolver.
      *
-     * @param callable|SequenceResolver $sequence
+     * @param  callable|SequenceResolver  $sequence
      */
     public function setSequenceResolver($sequence)
     {
@@ -179,7 +185,7 @@ public function setSequenceResolver($sequence)
     /**
      * Get Sequence Resolver.
      *
-     * @return null|callable|\Godruoyi\Snowflake\SequenceResolver
+     * @return SequenceResolver|null
      */
     public function getSequenceResolver()
     {
@@ -189,7 +195,7 @@ public function getSequenceResolver()
     /**
      * Get Default Sequence Resolver.
      *
-     * @return \Godruoyi\Snowflake\SequenceResolver
+     * @return SequenceResolver
      */
     public function getDefaultSequenceResolver(): SequenceResolver
     {
@@ -199,10 +205,7 @@ public function getDefaultSequenceResolver(): SequenceResolver
     /**
      * Call resolver.
      *
-     * @param callable|\Godruoyi\Snowflake\SequenceResolver $resolver
-     * @param int                                           $maxSequence
-     * @param mixed                                         $currentTime
-     *
+     * @param  mixed  $currentTime
      * @return int
      */
     protected function callResolver($currentTime)
@@ -213,7 +216,7 @@ protected function callResolver($currentTime)
             return $resolver($currentTime);
         }
 
-        return is_null($resolver) || !($resolver instanceof SequenceResolver)
+        return ! ($resolver instanceof SequenceResolver)
             ? $this->getDefaultSequenceResolver()->sequence($currentTime)
             : $resolver->sequence($currentTime);
     }