adding fqdn config item to be used on the payment url building (#23)

Author: theflyingcodr

config/config.go

@@ -12,6 +12,7 @@ import (
 const (
 	EnvServerPort           = "server.port"
 	EnvServerHost           = "server.host"
+	EnvServerFQDN           = "server.fqdn"
 	EnvServerSwaggerEnabled = "server.swagger.enabled"
 	EnvEnvironment          = "env.environment"
 	EnvBitcoinNetwork       = "env.bitcoin.network"
@@ -93,6 +94,9 @@ type Logging struct {
 type Server struct {
 	Port     string
 	Hostname string
+	// FQDN - fully qualified domain name, used to form the paymentRequest
+	// payment URL as this may be different from the hostname + port.
+	FQDN string
 	// SwaggerEnabled if true we will include an endpoint to serve swagger documents.
 	SwaggerEnabled bool
 }

config/defaults.go

@@ -13,6 +13,7 @@ func SetupDefaults() {
 	// Web server defaults
 	viper.SetDefault(EnvServerHost, "p4")
 	viper.SetDefault(EnvServerPort, ":8445")
+	viper.SetDefault(EnvServerFQDN, "p4:8445")
 	viper.SetDefault(EnvServerSwaggerEnabled, true)
 
 	// Environment Defaults

config/viper.go

@@ -26,6 +26,7 @@ func (v *ViperConfig) WithServer() ConfigurationLoader {
 		Port:           viper.GetString(EnvServerPort),
 		Hostname:       viper.GetString(EnvServerHost),
 		SwaggerEnabled: viper.GetBool(EnvServerSwaggerEnabled),
+		FQDN:           viper.GetString(EnvServerFQDN),
 	}
 	return v
 }

service/paymentrequest.go

@@ -57,7 +57,7 @@ func (p *paymentRequest) CreatePaymentRequest(ctx context.Context, args p4.Payme
 		FeeRate:             dests.Fees,
 		CreationTimestamp:   time.Now().UTC(),
 		ExpirationTimestamp: time.Now().Add(24 * time.Hour).UTC(),
-		PaymentURL:          fmt.Sprintf("http://%s%s/api/v1/payment/%s", p.walletCfg.Hostname, "", args.PaymentID),
+		PaymentURL:          fmt.Sprintf("http://%s/api/v1/payment/%s", p.walletCfg.FQDN, args.PaymentID),
 		Memo:                fmt.Sprintf("invoice %s", args.PaymentID),
 		MerchantData: &p4.MerchantData{
 			AvatarURL:    merchant.AvatarURL,