Added ToClientTimezone() function to convert time to client's local time.

pkg/utils/dwelling.go

@@ -1,6 +1,10 @@
 package utils
 
-import "strings"
+import (
+	"net/http"
+	"strings"
+	"time"
+)
 
 // MainSite returns homepage address depending on network used.
 func MainSite(host string) string {
@@ -12,3 +16,18 @@ func MainSite(host string) string {
 
 	return "https://arav.top"
 }
+
+// ToClientTimezone converts given time to timezone set in a
+// X-Client-Timezone header. If this header is not set, then
+// converts to UTC.
+func ToClientTimezone(t time.Time, r *http.Request) time.Time {
+	if tz := r.Header.Get("X-Client-Timezone"); tz != "" {
+		loc, err := time.LoadLocation(tz)
+		if err != nil {
+			return t.UTC()
+		}
+		return t.In(loc)
+	} else {
+		return t.UTC()
+	}
+}