enhance(model):调整自定义的日期类型，以及相关的查询。

model/types.go

@@ -19,10 +19,34 @@ func NewDate(t time.Time) Date {
 	}
 	t = t.In(loc)
 	return Date{
-		Time: time.Date(0, 1, 1, t.Hour(), t.Minute(), t.Second(), t.Nanosecond(), loc),
+		Time: time.Date(t.Year(), t.Month(), t.Day(), 0, 0, 0, 0, loc),
 	}
 }
 
+func NewEmptyDate() Date {
+	loc, err := time.LoadLocation("Asia/Shanghai")
+	if err != nil {
+		panic(err)
+	}
+	return Date{
+		Time: time.Date(0, 1, 1, 0, 0, 0, 0, loc),
+	}
+}
+
+func ParseDate(t string) (Date, error) {
+	loc, err := time.LoadLocation("Asia/Shanghai")
+	if err != nil {
+		return NewEmptyDate(), fmt.Errorf("unable to load time zone, %w", err)
+	}
+	d, err := time.ParseInLocation("2006-01-02", t, loc)
+	if err != nil {
+		return NewEmptyDate(), fmt.Errorf("unable to parse given time, %w", err)
+	}
+	return Date{
+		Time: d,
+	}, nil
+}
+
 var _ driver.Valuer = (*Date)(nil)
 
 func (d Date) Value() (driver.Value, error) {
@@ -62,7 +86,7 @@ func (d *Date) Scan(src interface{}) (err error) {
 var _ json.Marshaler = (*Date)(nil)
 
 func (d Date) MarshalJSON() ([]byte, error) {
-	return []byte(d.Time.Format("2006-01-02")), nil
+	return json.Marshal(d.Time.Format("2006-01-02"))
 }
 
 var _ json.Unmarshaler = (*Date)(nil)
@@ -72,7 +96,11 @@ func (d *Date) UnmarshalJSON(raw []byte) error {
 	if err != nil {
 		return fmt.Errorf("unable to load time zone, %w", err)
 	}
-	s := string(raw)
+	var s string
+	err = json.Unmarshal(raw, &s)
+	if err != nil {
+		return fmt.Errorf("unable to unmarshal value, %w", err)
+	}
 	d.Time, err = time.ParseInLocation("2006-01-02", s, loc)
 	return err
 }