created_at2022-04-16 11:09:57.970418
updated_at2024-01-26 05:14:50.722757
descriptionHigh-performance ISO8601 Timestamp formatting and parsing
Nova (novacrazy)



ISO8601 Timestamp Documentation MIT/Apache-2 licensed

This crate provides high-performance formatting and parsing routines for ISO8601 timestamps, primarily focused on UTC values but with support for parsing (and automatically applying) UTC Offsets.

The primary purpose of this is to keep the lightweight representation of timestamps within data structures, and only formatting it to a string when needed via Serde.

The Timestamp struct is only 12 bytes, while the formatted strings can be as large as 35 bytes, and care is taken to avoid heap allocations when formatting.


use serde::{Serialize, Deserialize};
use smol_str::SmolStr; // stack-allocation for small strings
use iso8601_timestamp::Timestamp;

#[derive(Debug, Clone, Serialize)]
pub struct Event {
    name: SmolStr,
    ts: Timestamp,
    value: i32,

when serialized to JSON could result in:

    "name": "some_event",
    "ts": "2021-10-17T02:03:01Z",
    "value": 42

When serializing to non-human-readable formats, such as binary formats, the Timestamp will be written as an i64 representing milliseconds since the Unix Epoch. This way it only uses 8 bytes instead of 24.

Similarly, when deserializing, it supports either an ISO8601 string or an i64 representing a unix timestamp in milliseconds.

Cargo Features

  • std (default)

    • Enables standard library features, such as getting the current time.
  • lookup (default)

    • Enables use of a 200-byte lookup table during formatting. Slightly faster with a hot cache. Disabling saves 200 bytes at a ~20% slowdown.
  • serde (default)

    • Enables serde implementations for Timestamp and TimestampStr
  • rkyv

    • Enables rkyv archive support for Timestamp, serializing it as a 64-bit signed unix offset in milliseconds.
  • verify

    • Verifies numeric inputs when parsing and fails when non-numeric input is found.
    • When disabled, parsing ignores invalid input, possibly giving garbage timestamps.
  • nightly

    • Enables nightly-specific optimizations, but without it will fallback to workarounds to enable the same optimizations.
  • pg

    • Enables ToSql/FromSql implementations for Timestamp so it can be directly stored/fetched from a PostgreSQL database using rust-postgres
  • rusqlite

    • Enables ToSql/FromSql implementations for Timestamp so it can be stored/fetched from an rusqlite/sqlite3 database
  • diesel/diesel-pg

    • Enables support for diesel ToSql/FromSql and AsExpression
  • schema

    • Enables implementation for JsonSchema for generating a JSON schema on the fly using schemars.
  • bson

    • Enables visit_map implementation to handle deserialising BSON (MongoDB) DateTime format, { $date: string }.
  • rand

    • Enables rand implementations, to generate random timestamps.
  • quickcheck

    • Enables quickcheck's Arbitrary implementation on Timestamp
  • worker

    • Enables support for now_utc() in Cloudflare workers
  • js

    • Enables support for now_utc() in WASM using js-sys
  • ramhorns

    • Implements Content for Timestamp, formatting it as a regular ISO8601 timestamp. Note that ramhorns is GPLv3.
Commit count: 108

cargo fmt