rust / (de)serialize DateTime to Sql

datetime.rs

use rusqlite::{ToSql, types::{FromSql, FromSqlResult, ToSqlOutput, ValueRef}};
use miniserde::{Deserialize, Serialize, de::Visitor, make_place, ser::Fragment};
use miniserde::Result;

make_place!(Place);

#[derive(Serialize, Clone, Deserialize, Debug)]
pub struct DateTime(
    pub time::OffsetDateTime
);

impl FromSql for DateTime {
    fn column_result(value: ValueRef) -> FromSqlResult<Self> {
        i64::column_result(value).map(|as_i64| {
            DateTime(time::OffsetDateTime::from_unix_timestamp(as_i64))
        })
    }
}

impl ToSql for DateTime {
    fn to_sql(&self) -> rusqlite::Result<ToSqlOutput> {
        Ok(self.0.timestamp().into())
    }
}

impl Serialize for DateTime {
    fn begin(&self) -> Fragment {
        Fragment::I64(self.0.timestamp().into())
    }
}

impl Deserialize for DateTime {
    fn begin(out: &mut Option<Self>) -> &mut dyn Visitor {
        impl Visitor for Place<DateTime> {
            fn negative(&mut self, n: i64) -> Result<()> {
                self.out = Some(DateTime(time::OffsetDateTime::from_unix_timestamp(n)));
                Ok(())
            }
        }
        Place::new(out)
    }
}