add multi instance manager

src/Illuminate/Support/MultipleInstanceManager.php

@@ -0,0 +1,186 @@
+<?php
+
+namespace Illuminate\Cache;
+
+use Closure;
+use InvalidArgumentException;
+
+abstract class MultipleInstanceManager
+{
+    /**
+     * The application instance.
+     *
+     * @var \Illuminate\Contracts\Foundation\Application
+     */
+    protected $app;
+
+    /**
+     * The array of resolved instances.
+     *
+     * @var array
+     */
+    protected $instances = [];
+
+    /**
+     * The registered custom instance creators.
+     *
+     * @var array
+     */
+    protected $customCreators = [];
+
+    /**
+     * Create a new manager instance.
+     *
+     * @param  \Illuminate\Contracts\Foundation\Application  $app
+     * @return void
+     */
+    public function __construct($app)
+    {
+        $this->app = $app;
+    }
+
+    /**
+     * Get the default instance name.
+     *
+     * @return string
+     */
+    abstract public function getDefaultInstance();
+
+    /**
+     * Set the default instance name.
+     *
+     * @param  string  $name
+     * @return void
+     */
+    abstract public function setDefaultInstance($name);
+
+    /**
+     * Get the instance specific configuration.
+     *
+     * @param  string  $name
+     * @return array
+     */
+    abstract public function getInstanceConfig($name);
+
+    /**
+     * Get an instance instance by name.
+     *
+     * @param  string|null  $name
+     * @return mixed
+     */
+    public function instance($name = null)
+    {
+        $name = $name ?: $this->getDefaultInstance();
+
+        return $this->instances[$name] = $this->get($name);
+    }
+
+    /**
+     * Attempt to get an instance from the local cache.
+     *
+     * @param  string  $name
+     * @return mixed
+     */
+    protected function get($name)
+    {
+        return $this->instances[$name] ?? $this->resolve($name);
+    }
+
+    /**
+     * Resolve the given instance.
+     *
+     * @param  string  $name
+     * @return mixed
+     *
+     * @throws \InvalidArgumentException
+     */
+    protected function resolve($name)
+    {
+        $config = $this->getInstanceConfig($name);
+
+        if (is_null($config)) {
+            throw new InvalidArgumentException("Instance [{$name}] is not defined.");
+        }
+
+        if (isset($this->customCreators[$config['driver']])) {
+            return $this->callCustomCreator($config);
+        } else {
+            $driverMethod = 'create'.ucfirst($config['driver']).'Driver';
+
+            if (method_exists($this, $driverMethod)) {
+                return $this->{$driverMethod}($config);
+            } else {
+                throw new InvalidArgumentException("Instance driver [{$config['driver']}] is not supported.");
+            }
+        }
+    }
+
+    /**
+     * Call a custom instance creator.
+     *
+     * @param  array  $config
+     * @return mixed
+     */
+    protected function callCustomCreator(array $config)
+    {
+        return $this->customCreators[$config['driver']]($this->app, $config);
+    }
+
+    /**
+     * Unset the given instances.
+     *
+     * @param  array|string|null  $name
+     * @return $this
+     */
+    public function forgetInstance($name = null)
+    {
+        $name = $name ?? $this->getDefaultInstance();
+
+        foreach ((array) $name as $instanceName) {
+            if (isset($this->instances[$instanceName])) {
+                unset($this->instances[$instanceName]);
+            }
+        }
+
+        return $this;
+    }
+
+    /**
+     * Disconnect the given instance and remove from local cache.
+     *
+     * @param  string|null  $name
+     * @return void
+     */
+    public function purge($name = null)
+    {
+        $name = $name ?? $this->getDefaultInstance();
+
+        unset($this->instances[$name]);
+    }
+
+    /**
+     * Register a custom instance creator Closure.
+     *
+     * @param  string  $name
+     * @param  \Closure  $callback
+     * @return $this
+     */
+    public function extend($name, Closure $callback)
+    {
+        $this->customCreators[$name] = $callback->bindTo($this, $this);
+
+        return $this;
+    }
+
+    /**
+     * Dynamically call the default instance.
+     *
+     * @param  string  $method
+     * @param  array  $parameters
+     * @return mixed
+     */
+    public function __call($method, $parameters)
+    {
+        return $this->instance()->$method(...$parameters);
+    }
+}