In the Savon site I found that options to pass the SSL certificate file, but I didin’t understand it, since why do we need to have the ssl certificate to consume the API? Also let me know the way to consume the SOAP service with SSL.
The specific error you’re getting is HTTPI complaining that the SSL cert of the remote server can’t be verified. You’ll need to include (at a minimum) the certificate of the CA who issued the remote server’s key in ssl_ca_cert_file (also in the documentation you linked to).