Improve compatibility with old browsers (#136)

Reviewed-on: #136

backend/main.go

@@ -43,6 +43,11 @@ type ServerConfig struct {
 	Started chan bool
 }
 
+const DefaultDomain = "localhost:8080"
+
+// The domain that the server is reachable at.
+var domain = DefaultDomain
+
 func getUsers(c *gin.Context) {
 	users, err := db.GetUsers()
 	if err != nil {
@@ -706,5 +711,10 @@ func main() {
 		config.Datasource = "allowance_planner.db3"
 		log.Printf("Warning: No DB_PATH set, using default of %s", config.Datasource)
 	}
+	domain = os.Getenv("DOMAIN")
+	if domain == "" {
+		domain = DefaultDomain
+		log.Printf("Warning: No DOMAIN set, using default of %s", domain)
+	}
 	start(context.Background(), &config)
 }