reifydb-store-multi 0.5.0

// SPDX-License-Identifier: Apache-2.0
// Copyright (c) 2025 ReifyDB

//! Multi-version storage backend for OLTP traffic. Implements the `MultiVersionStore` family of traits from
//! `core::interface::store` so the engine can read at a snapshot, write a new version, and step backwards through
//! history without coordinating with concurrent readers.
//!
//! The backend is tiered: hot writes land in the in-memory buffer, the flusher migrates them to persistent storage
//! at commit boundaries, and the garbage collector reclaims versions that have aged out behind the configured
//! retention. The persistent tier is pluggable - a SQLite-backed implementation is the default but the trait surface
//! is what the engine binds to, so other backends can be slotted in.
//!
//! Invariant: a row at `version V` is the value visible to a reader whose snapshot is `>= V` and where no later
//! version exists at `V' <= snapshot`. Commit must publish all deltas of a transaction atomically with respect to
//! readers; partial visibility breaks snapshot isolation.

#![cfg_attr(not(debug_assertions), deny(clippy::disallowed_methods))]
#![cfg_attr(debug_assertions, warn(clippy::disallowed_methods))]
#![cfg_attr(not(debug_assertions), deny(warnings))]
#![allow(clippy::tabs_in_doc_comments)]

use reifydb_core::{
	event::EventBus,
	interface::version::{ComponentType, HasVersion, SystemVersion},
};
use reifydb_type::Result;

pub mod buffer;
pub mod flush;
pub mod gc;
pub mod persistent;
pub mod tier;

pub mod config;
pub mod multi;
pub mod store;

use config::{BufferConfig, MultiStoreConfig};
use reifydb_core::{
	common::CommitVersion,
	delta::Delta,
	encoded::key::{EncodedKey, EncodedKeyRange},
	interface::store::{
		MultiVersionCommit, MultiVersionContains, MultiVersionGet, MultiVersionGetPrevious, MultiVersionRow,
		MultiVersionStore,
	},
};
use reifydb_type::util::cowvec::CowVec;
use store::StandardMultiStore;

pub mod memory {}
pub mod sqlite {}

pub struct MultiStoreVersion;

impl HasVersion for MultiStoreVersion {
	fn version(&self) -> SystemVersion {
		SystemVersion {
			name: env!("CARGO_PKG_NAME")
				.strip_prefix("reifydb-")
				.unwrap_or(env!("CARGO_PKG_NAME"))
				.to_string(),
			version: env!("CARGO_PKG_VERSION").to_string(),
			description: "Multi-version storage for OLTP operations with MVCC support".to_string(),
			r#type: ComponentType::Module,
		}
	}
}

#[repr(u8)]
#[derive(Clone)]
pub enum MultiStore {
	Standard(StandardMultiStore) = 0,
}

impl MultiStore {
	pub fn standard(config: MultiStoreConfig) -> Self {
		Self::Standard(StandardMultiStore::new(config).unwrap())
	}
}

impl MultiStore {
	pub fn testing_memory() -> Self {
		MultiStore::Standard(StandardMultiStore::testing_memory())
	}

	pub fn testing_memory_with_eventbus(event_bus: EventBus) -> Self {
		MultiStore::Standard(StandardMultiStore::testing_memory_with_eventbus(event_bus))
	}

	#[cfg(all(feature = "sqlite", not(target_arch = "wasm32")))]
	pub fn testing_memory_with_persistent_sqlite() -> Self {
		MultiStore::Standard(StandardMultiStore::testing_memory_with_persistent_sqlite())
	}

	#[cfg(all(feature = "sqlite", not(target_arch = "wasm32")))]
	pub fn testing_memory_with_persistent_sqlite_with_eventbus(event_bus: EventBus) -> Self {
		MultiStore::Standard(StandardMultiStore::testing_memory_with_persistent_sqlite_with_eventbus(event_bus))
	}

	pub fn flush_pending_blocking(&self) {
		match self {
			MultiStore::Standard(store) => store.flush_pending_blocking(),
		}
	}

	pub fn buffer(&self) -> Option<&buffer::tier::MultiBufferTier> {
		match self {
			MultiStore::Standard(store) => store.buffer(),
		}
	}

	pub fn persistent(&self) -> Option<&persistent::MultiPersistentTier> {
		match self {
			MultiStore::Standard(store) => store.persistent(),
		}
	}
}

impl MultiVersionGet for MultiStore {
	#[inline]
	fn get(&self, key: &EncodedKey, version: CommitVersion) -> Result<Option<MultiVersionRow>> {
		match self {
			MultiStore::Standard(store) => MultiVersionGet::get(store, key, version),
		}
	}
}

impl MultiVersionContains for MultiStore {
	#[inline]
	fn contains(&self, key: &EncodedKey, version: CommitVersion) -> Result<bool> {
		match self {
			MultiStore::Standard(store) => MultiVersionContains::contains(store, key, version),
		}
	}
}

impl MultiVersionCommit for MultiStore {
	#[inline]
	fn commit(&self, deltas: CowVec<Delta>, version: CommitVersion) -> Result<()> {
		match self {
			MultiStore::Standard(store) => store.commit(deltas, version),
		}
	}
}

impl MultiVersionGetPrevious for MultiStore {
	#[inline]
	fn get_previous_version(
		&self,
		key: &EncodedKey,
		before_version: CommitVersion,
	) -> Result<Option<MultiVersionRow>> {
		match self {
			MultiStore::Standard(store) => store.get_previous_version(key, before_version),
		}
	}
}

pub type MultiVersionRangeIterator<'a> = Box<dyn Iterator<Item = Result<MultiVersionRow>> + Send + 'a>;

impl MultiStore {
	pub fn range(
		&self,
		range: EncodedKeyRange,
		version: CommitVersion,
		batch_size: usize,
	) -> MultiVersionRangeIterator<'_> {
		match self {
			MultiStore::Standard(store) => Box::new(store.range(range, version, batch_size)),
		}
	}

	pub fn range_rev(
		&self,
		range: EncodedKeyRange,
		version: CommitVersion,
		batch_size: usize,
	) -> MultiVersionRangeIterator<'_> {
		match self {
			MultiStore::Standard(store) => Box::new(store.range_rev(range, version, batch_size)),
		}
	}
}

impl MultiVersionStore for MultiStore {}