lighthouse/beacon_node/store/src/memory_store.rs
Adam Szkoda 9db0c28051
Make key value storage abstractions more accurate (#1267)
* Layer do_atomically() abstractions properly

* Reduce allocs and DRY get_key_for_col()

* Parameterize HotColdDB with hot and cold item stores

* -impl Store for MemoryStore

* Replace Store uses with HotColdDB

* Ditch Store trait

* cargo fmt

* Style fix

* Readd missing dep that broke the build
2020-06-16 11:34:04 +10:00

80 lines
2.3 KiB
Rust

use super::{Error, ItemStore, KeyValueStore, KeyValueStoreOp};
use parking_lot::RwLock;
use std::collections::HashMap;
use std::marker::PhantomData;
use types::*;
type DBHashMap = HashMap<Vec<u8>, Vec<u8>>;
/// A thread-safe `HashMap` wrapper.
pub struct MemoryStore<E: EthSpec> {
db: RwLock<DBHashMap>,
_phantom: PhantomData<E>,
}
impl<E: EthSpec> Clone for MemoryStore<E> {
fn clone(&self) -> Self {
Self {
db: RwLock::new(self.db.read().clone()),
_phantom: PhantomData,
}
}
}
impl<E: EthSpec> MemoryStore<E> {
/// Create a new, empty database.
pub fn open() -> Self {
Self {
db: RwLock::new(HashMap::new()),
_phantom: PhantomData,
}
}
fn get_key_for_col(col: &str, key: &[u8]) -> Vec<u8> {
let mut col = col.as_bytes().to_vec();
col.append(&mut key.to_vec());
col
}
}
impl<E: EthSpec> KeyValueStore<E> for MemoryStore<E> {
/// Get the value of some key from the database. Returns `None` if the key does not exist.
fn get_bytes(&self, col: &str, key: &[u8]) -> Result<Option<Vec<u8>>, Error> {
let column_key = Self::get_key_for_col(col, key);
Ok(self.db.read().get(&column_key).cloned())
}
/// Puts a key in the database.
fn put_bytes(&self, col: &str, key: &[u8], val: &[u8]) -> Result<(), Error> {
let column_key = Self::get_key_for_col(col, key);
self.db.write().insert(column_key, val.to_vec());
Ok(())
}
/// Return true if some key exists in some column.
fn key_exists(&self, col: &str, key: &[u8]) -> Result<bool, Error> {
let column_key = Self::get_key_for_col(col, key);
Ok(self.db.read().contains_key(&column_key))
}
/// Delete some key from the database.
fn key_delete(&self, col: &str, key: &[u8]) -> Result<(), Error> {
let column_key = Self::get_key_for_col(col, key);
self.db.write().remove(&column_key);
Ok(())
}
fn do_atomically(&self, batch: &[KeyValueStoreOp]) -> Result<(), Error> {
for op in batch {
match op {
KeyValueStoreOp::DeleteKey(hash) => {
self.db.write().remove(hash);
}
}
}
Ok(())
}
}
impl<E: EthSpec> ItemStore<E> for MemoryStore<E> {}