Ttdfjt

main.CRITICAL: Unable to serialize value. "exception":"[object]
(InvalidArgumentException(code: 0): Unable to serialize value. at
/public_html/vendor/magento/framework/Serialize/Serializer/Json.php:26)"
[]

magento version: 2.2.6

current Json.php

<?php
/**
 * Copyright © Magento, Inc. All rights reserved.
 * See COPYING.txt for license details.
 */
namespace MagentoFrameworkSerializeSerializer;

use MagentoFrameworkSerializeSerializerInterface;

/**
 * Serialize data to JSON, unserialize JSON encoded data
 *
 * @api
 * @since 100.2.0
 */
class Json implements SerializerInterface

 /**
 * @inheritDoc
 * @since 100.2.0
 */
 public function serialize($data)
 
 $result = json_encode($data);
 if (false === $result) 
 throw new InvalidArgumentException('Unable to serialize value.');
 
 return $result;
 


 /**
 * @inheritDoc
 * @since 100.2.0
 */
 public function unserialize($string)
 
 $result = json_decode($string, true);
 if (json_last_error() !== JSON_ERROR_NONE) 
 throw new InvalidArgumentException('Unable to unserialize value.');
 
 return $result;
 

previous Json.php with fixes, i remember it created some issues on the site so i reverted back.

<?php
/**
 * Copyright © Magento, Inc. All rights reserved.
 * See COPYING.txt for license details.
 */
namespace MagentoFrameworkSerializeSerializer;

use MagentoFrameworkSerializeSerializerInterface;

/**
 * Serialize data to JSON, unserialize JSON encoded data
 *
 * @api
 * @since 100.2.0
 */
class Json implements SerializerInterface

 /**
 * @inheritDoc
 * @since 100.2.0
 */
 public function serialize($data)
 
 $result = json_encode($data);
 if (false === $result) 
 throw new InvalidArgumentException('Unable to serialize value.');
 
 return $result;
 


 /**
 * @inheritDoc
 * @since 100.2.0
 */
 public function unserialize($string)
 
 /* old function
 $result = json_decode($string, true);
 if (json_last_error() !== JSON_ERROR_NONE) 
 throw new InvalidArgumentException('Unable to unserialize value.');
 
 return $result;
 */
 if($this->is_serialized($string))
 
 $string = $this->serialize($string);
 
 $result = json_decode($string, true);
 if (json_last_error() !== JSON_ERROR_NONE) 
 throw new InvalidArgumentException('Unable to unserialize value.');

 
 return $result;
 

 function is_serialized($value, &$result = null)
 
 // Bit of a give away this one
 if (!is_string($value))
 
 return false;
 
 // Serialized false, return true. unserialize() returns false on an
 // invalid string or it could return false if the string is serialized
 // false, eliminate that possibility.
 if ($value === 'b:0;')
 
 $result = false;
 return true;
 
 $length = strlen($value);
 $end = '';
 switch ($value[0])
 
 case 's':
 if ($value[$length - 2] !== '"')
 
 return false;
 
 case 'b':
 case 'i':
 case 'd':
 // This looks odd but it is quicker than isset()ing
 $end .= ';';
 case 'a':
 case 'O':
 $end .= '';
 if ($value[1] !== ':')
 
 return false;
 
 switch ($value[2])
 
 case 0:
 case 1:
 case 2:
 case 3:
 case 4:
 case 5:
 case 6:
 case 7:
 case 8:
 case 9:
 break;
 default:
 return false;
 
 case 'N':
 $end .= ';';
 if ($value[$length - 1] !== $end[0])
 
 return false;
 
 break;
 default:
 return false;
 
 if (($result = @unserialize($value)) === false)
 
 $result = null;
 return false;
 
 return true;
 
}

similar issues:

Unable to Serialize Value Magento 2.2.6

Magento 2.2: Unable to unserialize value?