service_oauth_authentication.go
func serviceOAuth(certFilePath string) (*serviceOAuthAuthentication, error) {
	// First we read the cert
	certs := x509.NewCertPool()
	pemData, err := ioutil.ReadFile(certFilePath)
	if err != nil {
		return nil, err
	}
	certs.AppendCertsFromPEM(pemData)
	mTLSConfig := &tls.Config{
		RootCAs: certs, //Add the cert as a TLS config
	}
	a := serviceOAuthAuthentication{
		BaseUrl: "https://coinbase.com/",
		Client: http.Client{
			Transport: &http.Transport{
				Dial:            dialTimeout,
				TLSClientConfig: mTLSConfig,
			},
		},
	}
	return &a, nil
}
func serviceOAuth(certFilePath string) (*serviceOAuthAuthentication, error) {
	// First we read the cert
	certs := x509.NewCertPool()
	pemData, err := ioutil.ReadFile(certFilePath)
	if err != nil {
		return nil, err
	}
	certs.AppendCertsFromPEM(pemData)
	mTLSConfig := &tls.Config{
		RootCAs: certs, //Add the cert as a TLS config
	}
	a := serviceOAuthAuthentication{
		BaseUrl: "https://coinbase.com/",
		Client: http.Client{
			Transport: &http.Transport{
				Dial:            dialTimeout,
				TLSClientConfig: mTLSConfig,
			},
		},
	}
	return &a, nil
}
// ServiceOAuth instantiates ServiceOAuthAuthentication with the coinbase certificate file