1 files changed, 32 insertions, 0 deletions
diff --git a/client_options.go b/client_options.go
index 7f23c24..5ed7d2c 100644
--- a/client_options.go
+++ b/client_options.go
@@ -3,10 +3,42 @@
 
 package duitku
 
+import (
+	"fmt"
+	"net/url"
+)
+
 // ClientOptions configuration for HTTP client.
 type ClientOptions struct {
 	ServerUrl string
 	UserID    string
 	Email     string
 	ApiKey    string
+
+	// The hostname extracted from ServerUrl.
+	host string
+}
+
+// validate each field values.
+func (opts *ClientOptions) validate() (err error) {
+	var (
+		urlServer *url.URL
+	)
+
+	urlServer, err = url.Parse(opts.ServerUrl)
+	if err != nil {
+		return fmt.Errorf(`invalid or empty ServerUrl: %s`, opts.ServerUrl)
+	}
+	opts.host = urlServer.Host
+
+	if len(opts.UserID) == 0 {
+		return fmt.Errorf(`invalid or empty UserID: %s`, opts.UserID)
+	}
+	if len(opts.Email) == 0 {
+		return fmt.Errorf(`invalid or empty Email: %s`, opts.Email)
+	}
+	if len(opts.ApiKey) == 0 {
+		return fmt.Errorf(`invalid or empty ApiKey: %s`, opts.ApiKey)
+	}
+	return nil
 }