some improvements

src/HandlerResolver.php

@@ -0,0 +1,109 @@
+<?php
+
+namespace frostealth\yii2\aws\s3;
+
+use Aws\S3\S3Client;
+use frostealth\yii2\aws\s3\handlers\PlainCommandHandler;
+use frostealth\yii2\aws\s3\interfaces;
+use yii\base\Exception;
+use yii\base\Object;
+
+/**
+ * Class HandlerResolver
+ *
+ * @package frostealth\yii2\aws\s3
+ */
+class HandlerResolver extends Object implements interfaces\HandlerResolver
+{
+    /** @var array */
+    protected $handlers = [];
+
+    /** @var string */
+    protected $plainCommandHandlerClassName = PlainCommandHandler::class;
+
+    /** @var \Aws\S3\S3Client */
+    protected $s3Client;
+
+    /**
+     * HandlerResolver constructor.
+     *
+     * @param \Aws\S3\S3Client $s3Client
+     * @param array            $config
+     */
+    public function __construct(S3Client $s3Client, array $config = [])
+    {
+        $this->s3Client = $s3Client;
+        parent::__construct($config);
+    }
+
+    /**
+     * @param \frostealth\yii2\aws\s3\interfaces\commands\Command $command
+     *
+     * @return \frostealth\yii2\aws\s3\interfaces\handlers\Handler
+     * @throws \yii\base\Exception
+     */
+    public function resolve(interfaces\commands\Command $command): interfaces\handlers\Handler
+    {
+        $commandClass = get_class($command);
+
+        if (isset($this->handlers[$commandClass])) {
+            $handler = $this->handlers[$commandClass];
+
+            return is_object($handler) ? $handler : $this->createHandler($handler);
+        }
+
+        if ($command instanceof interfaces\commands\PlainCommand) {
+            return $this->createHandler($this->plainCommandHandlerClassName);
+        }
+
+        $handlerClass = $commandClass . 'Handler';
+        if (class_exists($handlerClass)) {
+            return $this->createHandler($handlerClass);
+        }
+
+        $handlerClass = str_replace('\\commands\\', '\\handlers\\', $handlerClass);
+        if (class_exists($handlerClass)) {
+            return $this->createHandler($handlerClass);
+        }
+
+        throw new Exception("Could not terminate the handler of a command of type \"{$commandClass}\"");
+    }
+
+    /**
+     * @param string $commandClass
+     * @param mixed  $handler
+     */
+    public function bindHandler(string $commandClass, $handler)
+    {
+        $this->handlers[$commandClass] = $handler;
+    }
+
+    /**
+     * @param array $handlers
+     */
+    public function setHandlers(array $handlers)
+    {
+        foreach ($handlers as $commandClass => $handler) {
+            $this->bindHandler($commandClass, $handler);
+        }
+    }
+
+    /**
+     * @param string $className
+     */
+    public function setPlainCommandHandler(string $className)
+    {
+        $this->plainCommandHandlerClassName = $className;
+    }
+
+    /**
+     * @param string|array $type
+     *
+     * @return \frostealth\yii2\aws\s3\interfaces\handlers\Handler
+     * @throws \yii\base\InvalidConfigException
+     */
+    protected function createHandler($type): interfaces\handlers\Handler
+    {
+        return \Yii::createObject($type, [$this->s3Client]);
+    }
+}