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use super::Error;
use rustc_hex::{FromHex, ToHex};
use serde::{
de::{Error as SerdeError, Visitor},
Deserialize, Deserializer, Serialize, Serializer,
};
use std::{fmt, str};
#[derive(Debug, PartialEq)]
pub struct Uuid([u8; 16]);
impl From<[u8; 16]> for Uuid {
fn from(uuid: [u8; 16]) -> Self {
Uuid(uuid)
}
}
impl<'a> Into<String> for &'a Uuid {
fn into(self) -> String {
let d1 = &self.0[0..4];
let d2 = &self.0[4..6];
let d3 = &self.0[6..8];
let d4 = &self.0[8..10];
let d5 = &self.0[10..16];
[d1, d2, d3, d4, d5]
.iter()
.map(|d| d.to_hex())
.collect::<Vec<String>>()
.join("-")
}
}
impl Into<String> for Uuid {
fn into(self) -> String {
Into::into(&self)
}
}
impl Into<[u8; 16]> for Uuid {
fn into(self) -> [u8; 16] {
self.0
}
}
impl fmt::Display for Uuid {
fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
let s: String = (self as &Uuid).into();
write!(f, "{}", s)
}
}
fn copy_into(from: &str, into: &mut [u8]) -> Result<(), Error> {
let from = from.from_hex().map_err(|_| Error::InvalidUuid)?;
if from.len() != into.len() {
return Err(Error::InvalidUuid);
}
into.copy_from_slice(&from);
Ok(())
}
impl str::FromStr for Uuid {
type Err = Error;
fn from_str(s: &str) -> Result<Self, Self::Err> {
let parts: Vec<&str> = s.split("-").collect();
if parts.len() != 5 {
return Err(Error::InvalidUuid);
}
let mut uuid = [0u8; 16];
copy_into(parts[0], &mut uuid[0..4])?;
copy_into(parts[1], &mut uuid[4..6])?;
copy_into(parts[2], &mut uuid[6..8])?;
copy_into(parts[3], &mut uuid[8..10])?;
copy_into(parts[4], &mut uuid[10..16])?;
Ok(Uuid(uuid))
}
}
impl From<&'static str> for Uuid {
fn from(s: &'static str) -> Self {
s.parse().expect(&format!(
"invalid string literal for {}: '{}'",
stringify!(Self),
s
))
}
}
impl Serialize for Uuid {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
let s: String = self.into();
serializer.serialize_str(&s)
}
}
impl<'a> Deserialize<'a> for Uuid {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'a>,
{
deserializer.deserialize_any(UuidVisitor)
}
}
struct UuidVisitor;
impl<'a> Visitor<'a> for UuidVisitor {
type Value = Uuid;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
write!(formatter, "a valid hex-encoded UUID")
}
fn visit_str<E>(self, value: &str) -> Result<Self::Value, E>
where
E: SerdeError,
{
value.parse().map_err(SerdeError::custom)
}
fn visit_string<E>(self, value: String) -> Result<Self::Value, E>
where
E: SerdeError,
{
self.visit_str(value.as_ref())
}
}
#[cfg(test)]
mod tests {
use super::Uuid;
#[test]
fn uuid_from_str() {
let uuid: Uuid = "3198bc9c-6672-5ab3-d995-4942343ae5b6".into();
assert_eq!(
uuid,
Uuid::from([
0x31, 0x98, 0xbc, 0x9c, 0x66, 0x72, 0x5a, 0xb3, 0xd9, 0x95, 0x49, 0x42, 0x34, 0x3a,
0xe5, 0xb6
])
);
}
#[test]
fn uuid_from_and_to_str() {
let from = "3198bc9c-6672-5ab3-d995-4942343ae5b6";
let uuid: Uuid = from.into();
let to: String = uuid.into();
assert_eq!(from, &to);
}
}