time/serde/timestamp/
milliseconds.rs

1//! Treat an [`OffsetDateTime`] as a [Unix timestamp] with milliseconds for
2//! the purposes of serde.
3//!
4//! Use this module in combination with serde's [`#[with]`][with] attribute.
5//!
6//! When deserializing, the offset is assumed to be UTC.
7//!
8//! [Unix timestamp]: https://en.wikipedia.org/wiki/Unix_time
9//! [with]: https://serde.rs/field-attrs.html#with
10
11use serde::{de, Deserialize, Deserializer, Serialize, Serializer};
12
13use crate::OffsetDateTime;
14
15/// Serialize an `OffsetDateTime` as its Unix timestamp with milliseconds
16#[inline]
17pub fn serialize<S: Serializer>(
18    datetime: &OffsetDateTime,
19    serializer: S,
20) -> Result<S::Ok, S::Error> {
21    let timestamp = datetime.unix_timestamp_nanos() / 1_000_000;
22    timestamp.serialize(serializer)
23}
24
25/// Deserialize an `OffsetDateTime` from its Unix timestamp with milliseconds
26#[inline]
27pub fn deserialize<'a, D: Deserializer<'a>>(deserializer: D) -> Result<OffsetDateTime, D::Error> {
28    let value: i128 = <_>::deserialize(deserializer)?;
29    OffsetDateTime::from_unix_timestamp_nanos(value * 1_000_000)
30        .map_err(|err| de::Error::invalid_value(de::Unexpected::Signed(err.value), &err))
31}
32
33/// Treat an `Option<OffsetDateTime>` as a [Unix timestamp] with milliseconds
34/// for the purposes of serde.
35///
36/// Use this module in combination with serde's [`#[with]`][with] attribute.
37///
38/// When deserializing, the offset is assumed to be UTC.
39///
40/// [Unix timestamp]: https://en.wikipedia.org/wiki/Unix_time
41/// [with]: https://serde.rs/field-attrs.html#with
42pub mod option {
43    use super::*;
44
45    /// Serialize an `Option<OffsetDateTime>` as its Unix timestamp with milliseconds
46    #[inline]
47    pub fn serialize<S: Serializer>(
48        option: &Option<OffsetDateTime>,
49        serializer: S,
50    ) -> Result<S::Ok, S::Error> {
51        option
52            .map(|timestamp| timestamp.unix_timestamp_nanos() / 1_000_000)
53            .serialize(serializer)
54    }
55
56    /// Deserialize an `Option<OffsetDateTime>` from its Unix timestamp with milliseconds
57    #[inline]
58    pub fn deserialize<'a, D: Deserializer<'a>>(
59        deserializer: D,
60    ) -> Result<Option<OffsetDateTime>, D::Error> {
61        Option::deserialize(deserializer)?
62            .map(|value: i128| OffsetDateTime::from_unix_timestamp_nanos(value * 1_000_000))
63            .transpose()
64            .map_err(|err| de::Error::invalid_value(de::Unexpected::Signed(err.value), &err))
65    }
66}