code refactor

pkg/avatars/gravatar_provider.go

@@ -0,0 +1,31 @@
+package avatars
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/mayswind/ezbookkeeping/pkg/models"
+	"github.com/mayswind/ezbookkeeping/pkg/utils"
+)
+
+// Reference: https://en.gravatar.com/site/implement/hash/
+const gravatarUrlFormat = "https://www.gravatar.com/avatar/%s"
+
+// GravatarAvatarProvider represents the gravatar avatar provider
+type GravatarAvatarProvider struct {
+}
+
+// NewGravatarAvatarProvider returns a new gravatar avatar provider
+func NewGravatarAvatarProvider() *GravatarAvatarProvider {
+	return &GravatarAvatarProvider{}
+}
+
+// GetAvatarUrl returns the gravatar url
+func (p *GravatarAvatarProvider) GetAvatarUrl(user *models.User) string {
+	email := user.Email
+	email = strings.TrimSpace(email)
+	email = strings.ToLower(email)
+	emailMd5 := utils.MD5EncodeToString([]byte(email))
+
+	return fmt.Sprintf(gravatarUrlFormat, emailMd5)
+}