adding timestamp to utils

timestamp/timestamp.go

@@ -0,0 +1,55 @@
+package timestamp
+
+import (
+    "fmt"
+    "time"
+)
+
+const Format = "2006-01-02 15:04:05"
+
+type Timestamp struct {
+    when time.Time
+}
+
+func Now() Timestamp {
+    return Timestamp{when: time.Now()}
+}
+
+func NewTimestamp(t time.Time) Timestamp {
+    return Timestamp{when: t}
+}
+
+func (t Timestamp) Add(d time.Duration) Timestamp {
+    return Timestamp{when: t.when.Add(d)}
+}
+
+func (t Timestamp) After(other Timestamp) bool {
+    return t.when.After(other.when)
+}
+
+func (t Timestamp) MarshalJSON() ([]byte, error) {
+    if t.when.IsZero() {
+        return []byte("\"\""), nil
+    }
+    return []byte(fmt.Sprintf("\"%s\"", t.when.Format(Format))), nil
+}
+
+func (t *Timestamp) UnmarshalJSON(b []byte) (err error) {
+    if string(b) == "\"\"" {
+        return
+    }
+    t.when, err = time.Parse(Format, string(b[1:len(b)-1]))
+    return
+}
+
+func (t Timestamp) Format(layout string) string {
+    return t.when.Format(layout)
+}
+
+func (t Timestamp) IsZero() bool {
+    return t.when.IsZero()
+}
+
+func (t Timestamp) Time() time.Time {
+    return t.when
+}