garage/src/util/data.rs
Alex Auvolat 1bcd6fabbd
New buckets for 0.6.0: small changes
- Fix bucket delete

- fix merge of bucket creation date

- Replace deletable with option in aliases
    Rationale: if two aliases point to conflicting bucket, resolving
    by making an arbitrary choice risks making data accessible when it
    shouldn't be. We'd rather resolve to deleting the alias until
    someone puts it back.
2022-01-04 12:52:47 +01:00

173 lines
4.1 KiB
Rust

//! Contains common types and functions related to serialization and integrity
use rand::Rng;
use serde::de::{self, Visitor};
use serde::{Deserialize, Deserializer, Serialize, Serializer};
use std::fmt;
/// An array of 32 bytes
#[derive(Default, Clone, Hash, PartialEq, Eq, PartialOrd, Ord, Copy)]
pub struct FixedBytes32([u8; 32]);
impl From<[u8; 32]> for FixedBytes32 {
fn from(x: [u8; 32]) -> FixedBytes32 {
FixedBytes32(x)
}
}
impl std::convert::AsRef<[u8]> for FixedBytes32 {
fn as_ref(&self) -> &[u8] {
&self.0[..]
}
}
impl fmt::Debug for FixedBytes32 {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "{}…", hex::encode(&self.0[..8]))
}
}
struct FixedBytes32Visitor;
impl<'de> Visitor<'de> for FixedBytes32Visitor {
type Value = FixedBytes32;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("a byte slice of size 32")
}
fn visit_bytes<E: de::Error>(self, value: &[u8]) -> Result<Self::Value, E> {
if value.len() == 32 {
let mut res = [0u8; 32];
res.copy_from_slice(value);
Ok(res.into())
} else {
Err(E::custom(format!(
"Invalid byte string length {}, expected 32",
value.len()
)))
}
}
}
impl<'de> Deserialize<'de> for FixedBytes32 {
fn deserialize<D: Deserializer<'de>>(deserializer: D) -> Result<FixedBytes32, D::Error> {
deserializer.deserialize_bytes(FixedBytes32Visitor)
}
}
impl Serialize for FixedBytes32 {
fn serialize<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error> {
serializer.serialize_bytes(&self.0[..])
}
}
impl FixedBytes32 {
/// Access the content as a slice
pub fn as_slice(&self) -> &[u8] {
&self.0[..]
}
/// Access the content as a mutable slice
pub fn as_slice_mut(&mut self) -> &mut [u8] {
&mut self.0[..]
}
/// Copy to a slice
pub fn to_vec(self) -> Vec<u8> {
self.0.to_vec()
}
/// Try building a FixedBytes32 from a slice
/// Return None if the slice is not 32 bytes long
pub fn try_from(by: &[u8]) -> Option<Self> {
if by.len() != 32 {
return None;
}
let mut ret = [0u8; 32];
ret.copy_from_slice(by);
Some(Self(ret))
}
}
impl From<netapp::NodeID> for FixedBytes32 {
fn from(node_id: netapp::NodeID) -> FixedBytes32 {
FixedBytes32::try_from(node_id.as_ref()).unwrap()
}
}
impl From<FixedBytes32> for netapp::NodeID {
fn from(bytes: FixedBytes32) -> netapp::NodeID {
netapp::NodeID::from_slice(bytes.as_slice()).unwrap()
}
}
/// A 32 bytes UUID
pub type Uuid = FixedBytes32;
/// A 256 bit cryptographic hash, can be sha256 or blake2 depending on provenance
pub type Hash = FixedBytes32;
/// Compute the sha256 of a slice
pub fn sha256sum(data: &[u8]) -> Hash {
use sha2::{Digest, Sha256};
let mut hasher = Sha256::new();
hasher.update(data);
let mut hash = [0u8; 32];
hash.copy_from_slice(&hasher.finalize()[..]);
hash.into()
}
/// Compute the blake2 of a slice
pub fn blake2sum(data: &[u8]) -> Hash {
use blake2::{Blake2b, Digest};
let mut hasher = Blake2b::new();
hasher.update(data);
let mut hash = [0u8; 32];
hash.copy_from_slice(&hasher.finalize()[..32]);
hash.into()
}
/// A 64 bit non cryptographic hash
pub type FastHash = u64;
/// Compute a (non cryptographic) of a slice
pub fn fasthash(data: &[u8]) -> FastHash {
use xxhash_rust::xxh3::Xxh3;
let mut h = Xxh3::new();
h.update(data);
h.digest()
}
/// Generate a random 32 bytes UUID
pub fn gen_uuid() -> Uuid {
rand::thread_rng().gen::<[u8; 32]>().into()
}
// RMP serialization with names of fields and variants
/// Serialize to MessagePack
pub fn rmp_to_vec_all_named<T>(val: &T) -> Result<Vec<u8>, rmp_serde::encode::Error>
where
T: Serialize + ?Sized,
{
let mut wr = Vec::with_capacity(128);
let mut se = rmp_serde::Serializer::new(&mut wr)
.with_struct_map()
.with_string_variants();
val.serialize(&mut se)?;
Ok(wr)
}
/// Serialize to JSON, truncating long result
pub fn debug_serialize<T: Serialize>(x: T) -> String {
match serde_json::to_string(&x) {
Ok(ss) => {
if ss.len() > 100 {
// TODO this can panic if 100 is not a codepoint boundary, but inside a 2 Bytes
// (or more) codepoint
ss[..100].to_string()
} else {
ss
}
}
Err(e) => format!("<JSON serialization error: {}>", e),
}
}