[FEATURE] Added Request::getContentType for content-type header-parsing

- Added unit-tests for Request::getContentType parsing.

src/Pecee/Http/Request.php

@@ -19,6 +19,10 @@ class Request
     public const REQUEST_TYPE_DELETE = 'delete';
     public const REQUEST_TYPE_HEAD = 'head';
 
+    public const CONTENT_TYPE_JSON = 'application/json';
+    public const CONTENT_TYPE_FORM_DATA = 'multipart/form-data';
+    public const CONTENT_TYPE_X_FORM_ENCODED = 'application/x-www-form-urlencoded';
+
     /**
      * All request-types
      * @var string[]
@@ -57,6 +61,12 @@ class Request
      */
     protected $headers = [];
 
+    /**
+     * Request ContentType
+     * @var string
+     */
+    protected $contentType;
+
     /**
      * Request host
      * @var string
@@ -117,10 +127,10 @@ class Request
         $this->setHost($this->getHeader('http-host'));
 
         // Check if special IIS header exist, otherwise use default.
-
-
         $this->setUrl(new Url($this->getFirstHeader(['unencoded-url', 'request-uri',])));
 
+        $this->setContentType(strtolower($this->getHeader('content-type')));
+
         $this->method = strtolower($this->getHeader('request-method'));
         $this->inputHandler = new InputHandler($this);
         $this->method = strtolower($this->inputHandler->value('_method', $this->getHeader('request-method')));
@@ -289,6 +299,31 @@ class Request
         return $defaultValue;
     }
 
+    /**
+     * Get request content-type
+     * @return string|null
+     */
+    public function getContentType(): ?string
+    {
+        return $this->contentType;
+    }
+
+    /**
+     * Set request content-type
+     * @param string $contentType
+     * @return $this
+     */
+    protected function setContentType(string $contentType): self
+    {
+        if(strpos($contentType, ';') > 0) {
+            $this->contentType = substr($contentType, 0, strpos($contentType, ';'));
+        } else {
+            $this->contentType = $contentType;
+        }
+
+        return $this;
+    }
+
     /**
      * Get input class
      * @return InputHandler
@@ -497,4 +532,4 @@ class Request
         return $this->data[$name] ?? null;
     }
 
-}
+}