diff --git a/samples/client/petstore-security-test/php/SwaggerClient-php/lib/Api/FakeApi.php b/samples/client/petstore-security-test/php/SwaggerClient-php/lib/Api/FakeApi.php
index 07f9f0e92f..7c6c1e4a8c 100644
--- a/samples/client/petstore-security-test/php/SwaggerClient-php/lib/Api/FakeApi.php
+++ b/samples/client/petstore-security-test/php/SwaggerClient-php/lib/Api/FakeApi.php
@@ -125,9 +125,6 @@ class FakeApi
         }
         $headerParams['Content-Type'] = $this->apiClient->selectHeaderContentType(['application/json', '*_/  \" =end --']);
 
-        // default format to json
-        $resourcePath = str_replace("{format}", "json", $resourcePath);
-
         // form params
         if ($test_code_inject____end____rn_n_r !== null) {
             $formParams['test code inject */ ' " =end -- \r\n \n \r'] = $this->apiClient->getSerializer()->toFormValue($test_code_inject____end____rn_n_r);
diff --git a/samples/client/petstore-security-test/php/SwaggerClient-php/lib/Configuration.php b/samples/client/petstore-security-test/php/SwaggerClient-php/lib/Configuration.php
index d430f0c771..5f19f8df53 100644
--- a/samples/client/petstore-security-test/php/SwaggerClient-php/lib/Configuration.php
+++ b/samples/client/petstore-security-test/php/SwaggerClient-php/lib/Configuration.php
@@ -39,7 +39,7 @@ namespace Swagger\Client;
  */
 class Configuration
 {
-    private static $defaultConfiguration = null;
+    private static $defaultConfiguration;
 
     /**
      * Associate array to store API key(s)
@@ -88,7 +88,7 @@ class Configuration
      *
      * @var string
      */
-    protected $host = 'https://petstore.swagger.io *_/ ' \" =end -- \\r\\n \\n \\r/v2 *_/ ' \" =end -- \\r\\n \\n \\r';
+    protected $host = 'https://petstore.swagger.io *_/ ' \" =end -- \\r\\n \\n \\r/v2 *_/ ' \" =end -- \\r\\n \\n \\r';
 
     /**
      * Timeout (second) of the HTTP request, by default set to 0, no timeout
@@ -109,7 +109,7 @@ class Configuration
      *
      * @var string
      */
-    protected $userAgent = "Swagger-Codegen/1.0.0/php";
+    protected $userAgent = 'Swagger-Codegen/1.0.0/php';
 
     /**
      * Debug switch (default set to false)
@@ -191,7 +191,7 @@ class Configuration
      * @param string $apiKeyIdentifier API key identifier (authentication scheme)
      * @param string $key              API key or token
      *
-     * @return Configuration
+     * @return $this
      */
     public function setApiKey($apiKeyIdentifier, $key)
     {
@@ -217,7 +217,7 @@ class Configuration
      * @param string $apiKeyIdentifier API key identifier (authentication scheme)
      * @param string $prefix           API key prefix, e.g. Bearer
      *
-     * @return Configuration
+     * @return $this
      */
     public function setApiKeyPrefix($apiKeyIdentifier, $prefix)
     {
@@ -242,7 +242,7 @@ class Configuration
      *
      * @param string $accessToken Token for OAuth
      *
-     * @return Configuration
+     * @return $this
      */
     public function setAccessToken($accessToken)
     {
@@ -265,7 +265,7 @@ class Configuration
      *
      * @param string $username Username for HTTP basic authentication
      *
-     * @return Configuration
+     * @return $this
      */
     public function setUsername($username)
     {
@@ -288,7 +288,7 @@ class Configuration
      *
      * @param string $password Password for HTTP basic authentication
      *
-     * @return Configuration
+     * @return $this
      */
     public function setPassword($password)
     {
@@ -312,7 +312,8 @@ class Configuration
      * @param string $headerName  header name (e.g. Token)
      * @param string $headerValue header value (e.g. 1z8wp3)
      *
-     * @return Configuration
+     * @throws \InvalidArgumentException
+     * @return $this
      */
     public function addDefaultHeader($headerName, $headerValue)
     {
@@ -339,11 +340,12 @@ class Configuration
      *
      * @param string $headerName the header to delete
      *
-     * @return Configuration
+     * @return $this
      */
     public function deleteDefaultHeader($headerName)
     {
         unset($this->defaultHeaders[$headerName]);
+        return $this;
     }
 
     /**
@@ -351,7 +353,7 @@ class Configuration
      *
      * @param string $host Host
      *
-     * @return Configuration
+     * @return $this
      */
     public function setHost($host)
     {
@@ -374,7 +376,8 @@ class Configuration
      *
      * @param string $userAgent the user agent of the api client
      *
-     * @return Configuration
+     * @throws \InvalidArgumentException
+     * @return $this
      */
     public function setUserAgent($userAgent)
     {
@@ -401,7 +404,8 @@ class Configuration
      *
      * @param integer $seconds Number of seconds before timing out [set to 0 for no timeout]
      *
-     * @return Configuration
+     * @throws \InvalidArgumentException
+     * @return $this
      */
     public function setCurlTimeout($seconds)
     {
@@ -428,7 +432,8 @@ class Configuration
      *
      * @param integer $seconds Number of seconds before connection times out [set to 0 for no timeout]
      *
-     * @return Configuration
+     * @throws \InvalidArgumentException
+     * @return $this
      */
     public function setCurlConnectTimeout($seconds)
     {
@@ -456,7 +461,7 @@ class Configuration
      *
      * @param string $proxyHost HTTP Proxy URL
      *
-     * @return ApiClient
+     * @return $this
      */
     public function setCurlProxyHost($proxyHost)
     {
@@ -479,7 +484,7 @@ class Configuration
      *
      * @param integer $proxyPort HTTP Proxy Port
      *
-     * @return ApiClient
+     * @return $this
      */
     public function setCurlProxyPort($proxyPort)
     {
@@ -502,7 +507,7 @@ class Configuration
      *
      * @param integer $proxyType HTTP Proxy Type
      *
-     * @return ApiClient
+     * @return $this
      */
     public function setCurlProxyType($proxyType)
     {
@@ -525,7 +530,7 @@ class Configuration
      *
      * @param string $proxyUser HTTP Proxy User
      *
-     * @return ApiClient
+     * @return $this
      */
     public function setCurlProxyUser($proxyUser)
     {
@@ -548,7 +553,7 @@ class Configuration
      *
      * @param string $proxyPassword HTTP Proxy Password
      *
-     * @return ApiClient
+     * @return $this
      */
     public function setCurlProxyPassword($proxyPassword)
     {
@@ -571,7 +576,7 @@ class Configuration
      *
      * @param bool $debug Debug flag
      *
-     * @return Configuration
+     * @return $this
      */
     public function setDebug($debug)
     {
@@ -594,7 +599,7 @@ class Configuration
      *
      * @param string $debugFile Debug file
      *
-     * @return Configuration
+     * @return $this
      */
     public function setDebugFile($debugFile)
     {
@@ -617,7 +622,7 @@ class Configuration
      *
      * @param string $tempFolderPath Temp folder path
      *
-     * @return Configuration
+     * @return $this
      */
     public function setTempFolderPath($tempFolderPath)
     {
@@ -640,7 +645,7 @@ class Configuration
      *
      * @param boolean $sslVerification True if the certificate should be validated, false otherwise
      *
-     * @return Configuration
+     * @return $this
      */
     public function setSSLVerification($sslVerification)
     {
@@ -693,7 +698,7 @@ class Configuration
     {
         $report  = 'PHP SDK (Swagger\Client) Debug Report:' . PHP_EOL;
         $report .= '    OS: ' . php_uname() . PHP_EOL;
-        $report .= '    PHP Version: ' . phpversion() . PHP_EOL;
+        $report .= '    PHP Version: ' . PHP_VERSION . PHP_EOL;
         $report .= '    OpenAPI Spec Version: 1.0.0 *_/ ' \" =end -- \\r\\n \\n \\r' . PHP_EOL;
         $report .= '    Temp Folder Path: ' . self::getDefaultConfiguration()->getTempFolderPath() . PHP_EOL;
 
diff --git a/samples/client/petstore-security-test/php/SwaggerClient-php/lib/ObjectSerializer.php b/samples/client/petstore-security-test/php/SwaggerClient-php/lib/ObjectSerializer.php
index 4bfe77988b..759790e17e 100644
--- a/samples/client/petstore-security-test/php/SwaggerClient-php/lib/ObjectSerializer.php
+++ b/samples/client/petstore-security-test/php/SwaggerClient-php/lib/ObjectSerializer.php
@@ -59,10 +59,16 @@ class ObjectSerializer
             return $data;
         } elseif (is_object($data)) {
             $values = [];
-            foreach (array_keys($data::swaggerTypes()) as $property) {
+            foreach ($data::swaggerTypes() as $property => $swaggerType) {
                 $getter = $data::getters()[$property];
-                if ($data->$getter() !== null) {
-                    $values[$data::attributeMap()[$property]] = self::sanitizeForSerialization($data->$getter());
+                $value = $data->$getter();
+                if (method_exists($swaggerType, 'getAllowableEnumValues')
+                    && !in_array($value, $swaggerType::getAllowableEnumValues())) {
+                    $imploded = implode("', '", $swaggerType::getAllowableEnumValues());
+                    throw new \InvalidArgumentException("Invalid value for enum '$swaggerType', must be one of: '$imploded'");
+                }
+                if ($value !== null) {
+                    $values[$data::attributeMap()[$property]] = self::sanitizeForSerialization($value);
                 }
             }
             return (object)$values;
@@ -269,6 +275,12 @@ class ObjectSerializer
             }
 
             return $deserialized;
+        } elseif (method_exists($class, 'getAllowableEnumValues')) {
+            if (!in_array($data, $class::getAllowableEnumValues())) {
+                $imploded = implode("', '", $class::getAllowableEnumValues());
+                throw new \InvalidArgumentException("Invalid value for enum '$class', must be one of: '$imploded'");
+            }
+            return $data;
         } else {
             // If a discriminator is defined and points to a valid subclass, use it.
             $discriminator = $class::DISCRIMINATOR;