Crate base64id

This crate allows for fixed length 64, 32 and 16 bit integers to be represented as base64url encoded strings. This is useful for exchanging unique identifiers in a web based contexts; eg. sending an SQL primary key to a client with as few character as possible.

This crate is #![no_std].

Quick Start

Add the following to your Cargo.toml file.

[dependencies]
base64id = "0.4"

Encoding

You can convert signed or unsigned integers to a Base64Id struct as follows:

use base64id::Base64Id;

#[derive(Base64Id)]
struct MyId(i64);

fn main() {
    let int: i64 = 1;
    let id = MyId::from(int);

    println!("{id}"); // AAAAAAAAAAE
}

Decoding

You can use FromStr and From<{integer}> to convert a String to a Base64Id struct and then into an i64 as follows:

use base64id::{Base64Id, Error};
use std::str::FromStr;

#[derive(Base64Id)]
struct MyId(i64);

fn main() -> Result<(), Error> {
    let id_str = MyId::from_str("PDFehCFVGqA")?;
    let id_int = i64::from(id_str);

    println!("{}", id_int); // 4337351837722417824

    Ok(())
}

Refer to the Error enum regarding decode errors.

Serde

Support for Serde is possible through the use of the base64id derive macro helper attribute.

use base64id::Base64Id;
use serde_json::Result;

#[derive(Base64Id)]
#[base64id(Serialize, Deserialize)]
struct MyId(i32);

fn main() -> Result<()> {
    let id = MyId(897100256);

    println!("{}", serde_json::to_string(&id)?); // "NXip4A"

    Ok(())
}

Enums

Error

Enum for base64url decoding errors

Derive Macros

Base64Id

Create your own base64id tuple struct