garage/src/model/object_table.rs
Alex Auvolat 08bcd51956
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continuous-integration/drone/push Build is passing
GC object table in a specific case
2021-03-16 16:51:15 +01:00

230 lines
5.2 KiB
Rust

use serde::{Deserialize, Serialize};
use std::collections::BTreeMap;
use std::sync::Arc;
use garage_util::background::BackgroundRunner;
use garage_util::data::*;
use garage_table::crdt::*;
use garage_table::replication::sharded::*;
use garage_table::*;
use crate::version_table::*;
#[derive(PartialEq, Clone, Debug, Serialize, Deserialize)]
pub struct Object {
// Primary key
pub bucket: String,
// Sort key
pub key: String,
// Data
versions: Vec<ObjectVersion>,
}
impl Object {
pub fn new(bucket: String, key: String, versions: Vec<ObjectVersion>) -> Self {
let mut ret = Self {
bucket,
key,
versions: vec![],
};
for v in versions {
ret.add_version(v)
.expect("Twice the same ObjectVersion in Object constructor");
}
ret
}
/// Adds a version if it wasn't already present
pub fn add_version(&mut self, new: ObjectVersion) -> Result<(), ()> {
match self
.versions
.binary_search_by(|v| v.cmp_key().cmp(&new.cmp_key()))
{
Err(i) => {
self.versions.insert(i, new);
Ok(())
}
Ok(_) => Err(()),
}
}
pub fn versions(&self) -> &[ObjectVersion] {
&self.versions[..]
}
}
#[derive(PartialEq, Clone, Debug, Serialize, Deserialize)]
pub struct ObjectVersion {
pub uuid: UUID,
pub timestamp: u64,
pub state: ObjectVersionState,
}
#[derive(PartialEq, Clone, Debug, Serialize, Deserialize)]
pub enum ObjectVersionState {
Uploading(ObjectVersionHeaders),
Complete(ObjectVersionData),
Aborted,
}
impl CRDT for ObjectVersionState {
fn merge(&mut self, other: &Self) {
use ObjectVersionState::*;
match other {
Aborted => {
*self = Aborted;
}
Complete(b) => match self {
Aborted => {}
Complete(a) => {
a.merge(b);
}
Uploading(_) => {
*self = Complete(b.clone());
}
},
Uploading(_) => {}
}
}
}
#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Debug, Serialize, Deserialize)]
pub enum ObjectVersionData {
DeleteMarker,
Inline(ObjectVersionMeta, #[serde(with = "serde_bytes")] Vec<u8>),
FirstBlock(ObjectVersionMeta, Hash),
}
impl AutoCRDT for ObjectVersionData {
const WARN_IF_DIFFERENT: bool = true;
}
#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Debug, Serialize, Deserialize)]
pub struct ObjectVersionMeta {
pub headers: ObjectVersionHeaders,
pub size: u64,
pub etag: String,
}
#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Debug, Serialize, Deserialize)]
pub struct ObjectVersionHeaders {
pub content_type: String,
pub other: BTreeMap<String, String>,
}
impl ObjectVersion {
fn cmp_key(&self) -> (u64, UUID) {
(self.timestamp, self.uuid)
}
pub fn is_uploading(&self) -> bool {
match self.state {
ObjectVersionState::Uploading(_) => true,
_ => false,
}
}
pub fn is_complete(&self) -> bool {
match self.state {
ObjectVersionState::Complete(_) => true,
_ => false,
}
}
pub fn is_data(&self) -> bool {
match self.state {
ObjectVersionState::Complete(ObjectVersionData::DeleteMarker) => false,
ObjectVersionState::Complete(_) => true,
_ => false,
}
}
}
impl Entry<String, String> for Object {
fn partition_key(&self) -> &String {
&self.bucket
}
fn sort_key(&self) -> &String {
&self.key
}
fn is_tombstone(&self) -> bool {
self.versions.len() == 1 && self.versions[0].state == ObjectVersionState::Complete(ObjectVersionData::DeleteMarker)
}
}
impl CRDT for Object {
fn merge(&mut self, other: &Self) {
// Merge versions from other into here
for other_v in other.versions.iter() {
match self
.versions
.binary_search_by(|v| v.cmp_key().cmp(&other_v.cmp_key()))
{
Ok(i) => {
self.versions[i].state.merge(&other_v.state);
}
Err(i) => {
self.versions.insert(i, other_v.clone());
}
}
}
// Remove versions which are obsolete, i.e. those that come
// before the last version which .is_complete().
let last_complete = self
.versions
.iter()
.enumerate()
.rev()
.filter(|(_, v)| v.is_complete())
.next()
.map(|(vi, _)| vi);
if let Some(last_vi) = last_complete {
self.versions = self.versions.drain(last_vi..).collect::<Vec<_>>();
}
}
}
pub struct ObjectTable {
pub background: Arc<BackgroundRunner>,
pub version_table: Arc<Table<VersionTable, TableShardedReplication>>,
}
impl TableSchema for ObjectTable {
type P = String;
type S = String;
type E = Object;
type Filter = DeletedFilter;
fn updated(&self, old: Option<Self::E>, new: Option<Self::E>) {
let version_table = self.version_table.clone();
self.background.spawn(async move {
if let (Some(old_v), Some(new_v)) = (old, new) {
// Propagate deletion of old versions
for v in old_v.versions.iter() {
let newly_deleted = match new_v
.versions
.binary_search_by(|nv| nv.cmp_key().cmp(&v.cmp_key()))
{
Err(_) => true,
Ok(i) => {
new_v.versions[i].state == ObjectVersionState::Aborted
&& v.state != ObjectVersionState::Aborted
}
};
if newly_deleted {
let deleted_version =
Version::new(v.uuid, old_v.bucket.clone(), old_v.key.clone(), true);
version_table.insert(&deleted_version).await?;
}
}
}
Ok(())
})
}
fn matches_filter(entry: &Self::E, filter: &Self::Filter) -> bool {
let deleted = !entry.versions.iter().any(|v| v.is_data());
filter.apply(deleted)
}
}