php - Why isn't my XML API request accepted by the API?

I have been trying, for days, to send a simple XML request to an API. Even with the help of the tech support, absolutely nothing works. I still get an error telling me that my XML isn't well-formed or is invalid.

Here is my cURL request:

$data = array_merge([
            'ssl_transaction_type' => "$transactionType",
            'ssl_merchant_id' => $this->merchant_id,
            'ssl_user_id' => $this->user_id,
            'ssl_pin' => $this->pin
        ], $data);
        
        $xml = new \SimpleXMLElement('<txn/>');
        $data = array_flip($data);
        array_walk_recursive($data, array ($xml, 'addChild'));
    
        $ch = curl_init(); 
        curl_setopt($ch, CURLOPT_URL, $this->getXMLUrl());
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
        curl_setopt($ch, CURLOPT_POST, true);
        curl_setopt($ch, CURLOPT_HTTPHEADER, array(
            'Content-type: application/x-www-form-urlencoded'
        ));     
        curl_setopt($ch, CURLOPT_POSTFIELDS, http_build_query(array("xmldata=" . explode(PHP_EOL, $xml->asXML())[1])));
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
        curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false);
    
        $response = curl_exec($ch);
Copy code

Why do I explode the XML? It's because I need to only get the part with the root, not the version, etc. according to the tech support.

I followed this: XML request is not well-formed or request is incomplete but it still doesn't work.

Didn't find the answer?

Our community is visited by hundreds of web development professionals every day. Ask your question and get a quick answer for free.