Kdjykuj

There has been similar issues posted without an answer unfortunately but I am posting two ways in the API to set a category on a product both of which give different errors.

The first is using the categories repository (catalogCategoryLinkRepositoryV1)

example
In body POST

{ 

    "productLink" :

    { 

        "sku" : "TEST_SKU5",  

        "position" : 0, 

        "categoryId" : "8",

        "extensionAttributes": {}



    }

} 

Example Response : This is the same response regardless of what category or product.

{

  "message": "Could not save product "%1" with position %2 to category %3",

  "parameters": [

    "144",

    0,

    "8"

  ]

}

The second is setting it under custom_attribute using the product repository in either new or update calls. Both give the same result.

When setting the custom_attribute like below regardless of what sku and category I get an error. If I leave out "category_ids" it works fine but defeats the purpose of using the API to manage product import and updates.

'custom_attributes' => array(

            array( 'attribute_code' => 'category_ids', 'value' => ["8"] ),

            array( 'attribute_code' => 'description', 'value' => 'Simple Description' ),

            array( 'attribute_code' => 'short_description', 'value' => 'Simple  Short Description' ),

            )

Error being the following, which is the only error I get regardless of what combination of sku and category even if the sku is not made yet and I am creating a new product..

"{"message":"URL key for specified store already exists."}"

You have to check below code for set product in category with position,

   <?php            

        $url="http://127.0.0.1/magento2.1/"; //your custom site url...

        $token_url=$url."rest/V1/integration/admin/token";



        //Below 9 is category id....

        $product_url=$url. "rest/V1/categories/9/products"; 

        $username="admin";

        $password="admin123";

        //Authentication rest API magento2, get access token

        $ch = curl_init();

        $data = array("username" => $username, "password" => $password);

        $data_string = json_encode($data);



        $ch = curl_init($token_url);

        curl_setopt($ch, CURLOPT_CUSTOMREQUEST, "POST");

        curl_setopt($ch, CURLOPT_POSTFIELDS, $data_string);

        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);

        curl_setopt($ch, CURLOPT_HTTPHEADER, array(

            'Content-Type: application/json',

            'Content-Length: ' . strlen($data_string))

            );

        $token = curl_exec($ch);

        $adminToken=  json_decode($token);



        //9 is category id...

        $sampleProductData = array(

                    "sku" => "24-MB01",

                    "position" => 5,

                    "category_id" => "9",

                    "extension_attributes" => array()

        );

        $categoryData = json_encode(array('productLink' => $sampleProductData));



        $setHaders = array('Content-Type:application/json','Authorization:Bearer '.$adminToken);

        $ch = curl_init();

        curl_setopt($ch,CURLOPT_URL, $product_url);

        curl_setopt($ch,CURLOPT_POSTFIELDS, $categoryData);

        curl_setopt($ch, CURLOPT_CUSTOMREQUEST, "POST");

        curl_setopt($ch, CURLOPT_HTTPHEADER, $setHaders);

        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);

        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);

        $response = curl_exec($ch);

        curl_close($ch);