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