Add MapPool component.

Author: twose

src/MapPool.php

@@ -0,0 +1,131 @@
+<?php
+/**
+ * Copyright: Swlib
+ * Author: Twosee <twose@qq.com>
+ * Date: 2018/6/30 下午6:03
+ */
+
+namespace Swlib\Util;
+
+use Swoole\Coroutine\Channel;
+
+/**
+ * Class MapPool
+ * Use SplQueue(unlimited) or Channel(max_size)
+ * @package Swlib\Util
+ */
+class MapPool
+{
+
+    use Singleton;
+
+    /** @var Channel[]|\SplQueue[] */
+    protected $resource_map = [];
+    /** @var [][] */
+    protected $status_map = [];
+
+    public function init(string $key, int $max_size = -1): bool
+    {
+        if (!isset($this->resource_map[$key])) {
+            if ($max_size < 0) {
+                $this->resource_map[$key] = new \SplQueue();
+            } else {
+                $this->resource_map[$key] = new Channel($max_size);
+            }
+            $this->status_map[$key] = [
+                'max' => $max_size,
+                'existing' => 0
+            ];
+            return true;
+        }
+        return false;
+    }
+
+    public function create(array $options, string $key = null)
+    {
+        if (!$key) {
+            throw new \InvalidArgumentException('Argument#2 $key can not be empty!');
+        }
+        @$this->status_map[$key]['existing']++;
+    }
+
+    public function get(string $key)
+    {
+        if (!isset($this->resource_map[$key])) {
+            $this->init($key);
+        }
+        $pool = $this->resource_map[$key];
+        if ($pool instanceof \SplQueue) {
+            $available = $this->resource_map[$key]->count() > 0;
+        } else {
+            // the resource available or over the max num, use pop or yield and waiting
+            $available = $this->resource_map[$key]->length() > 0 || $this->status_map[$key]['existing'] >= $this->status_map[$key]['max'];
+        }
+        if ($available) {
+            return $this->resource_map[$key]->pop();
+        } else {
+            return null; // need create new one
+        }
+    }
+
+    public function put($value, string $key = null)
+    {
+        if (!$key) {
+            throw new \InvalidArgumentException('Argument#2 $key can not be empty!');
+        }
+        $this->resource_map[$key]->push($value);
+    }
+
+    public function getStatus(string $key): array
+    {
+        if (!isset($this->status_map[$key])) {
+            return [
+                'max' => null,
+                'existing' => null,
+                'in_queue' => null
+            ];
+        } else {
+            $pool = $this->resource_map[$key];
+            $in_queue = $pool instanceof \SplQueue ? $pool->count() : $pool->length();
+            $this->status_map[$key]['in_queue'] = $in_queue;
+            return $this->status_map[$key];
+        }
+    }
+
+    public function getMax(string $key): ?int
+    {
+        return $this->status_map[$key]['max'] ?? null;
+    }
+
+    /**
+     * expend will create the new chan
+     *
+     * @param string $key
+     * @param int $max_size
+     * @return int do what
+     */
+    public function setMax(string $key, int $max_size = -1): int
+    {
+        $is_exist = !$this->init($key, $max_size);
+        if ($is_exist && $this->resource_map[$key] instanceof Channel) {
+            $current_max = $this->status_map[$key]['max'];
+            $this->status_map[$key]['max'] = $max_size;
+            if ($max_size > $current_max || $max_size < 0) { // expend or unlimited
+                if ($max_size < 0) { // chan to queue
+                    $new_pool = new \SplQueue();
+                } else {
+                    $new_pool = new Channel($max_size);
+                }
+                $old_chan = $this->resource_map[$key];
+                while (!$old_chan->isEmpty()) {
+                    $new_pool->push($old_chan->pop());
+                }
+                $old_chan->close();
+                return 1; // expend
+            } elseif ($max_size < $this->status_map[$key]['max']) {
+                return -1; // reduce
+            }
+        }
+        return 0; // do nothing
+    }
+}