How to set request headers in SOAP request using NuSOAP toolkit - api

Question

could anyone tell me how to add request headers for subscription keys in SOAP request.
I am using NuSOAP toolkit for making SOAP calls. Setting keys for authorisation SOAP calls seems difficult for me. Unless I pass the subscription keys in request headers, I didn't get an access.
I tried:
$this->nusoap_client->setHeaders("<soapHeader xmlns='http://test.com/'>
<Ocp-Apim-Subscription-Key>***mykey***</Ocp-Apim-Subscription-Key>
</soapHeader>");
but it adding keys to the soap header instead of request header.
Then I tried :
header("Ocp-Apim-Subscription-Key: ***mykey***");
but still no hope, its added to the response header now.
I am using $this->nusoap_client->call() for making SOAP call, and the response getting is
{ "statusCode": 401, "message": "Access denied due to missing subscription key. Make sure to include subscription key when making requests to an API." }
thanks in advance.

Answer 1

Well, I found a solution myself. Don't know if it is the right way or not! Anyway I would like to post my solution here, it may find useful to someone.
I solved this issue by modifying the nusoap library class file. Modified function soap_transport_http to set headers as:
$this->setHeader('Ocp-Apim-Subscription-Key', '***myKey***');
May be it is not the right way to modify headers in SOAP request, but it works for me. Please put your answer if you find better solution.