kv_core/storage/
mod.rs

1//! Storage implementations for the KV service
2//! 
3//! Provides different storage backends: in-memory, disk persistence, and AOF.
4
5pub mod memory;
6pub mod disk;
7pub mod aof;
8
9pub use memory::MemoryStorage;
10pub use disk::DiskStorage;
11pub use aof::AOFStorage;
12
13use async_trait::async_trait;
14use crate::{KVResult, Key, Entry, DatabaseId, PersistenceMode};
15
16/// Trait for storage backends
17#[async_trait]
18pub trait Storage: Send + Sync {
19    /// Get an entry by key
20    async fn get(&self, database_id: DatabaseId, key: &Key) -> KVResult<Option<Entry>>;
21    
22    /// Set an entry
23    async fn set(&self, database_id: DatabaseId, key: Key, entry: Entry) -> KVResult<()>;
24    
25    /// Delete an entry
26    async fn delete(&self, database_id: DatabaseId, key: &Key) -> KVResult<bool>;
27    
28    /// Check if a key exists
29    async fn exists(&self, database_id: DatabaseId, key: &Key) -> KVResult<bool>;
30    
31    /// Get all keys in a database
32    async fn keys(&self, database_id: DatabaseId) -> KVResult<Vec<Key>>;
33    
34    /// Get keys matching a pattern
35    async fn keys_pattern(&self, database_id: DatabaseId, pattern: &str) -> KVResult<Vec<Key>>;
36    
37    /// Clear all data in a database
38    async fn clear_database(&self, database_id: DatabaseId) -> KVResult<()>;
39    
40    /// Get database statistics
41    async fn get_stats(&self, database_id: DatabaseId) -> KVResult<StorageStats>;
42    
43    /// Flush all pending writes
44    async fn flush(&self) -> KVResult<()>;
45    
46    /// Close the storage backend
47    async fn close(&self) -> KVResult<()>;
48}
49
50/// Statistics for storage usage
51#[derive(Debug, Clone)]
52pub struct StorageStats {
53    pub total_keys: u64,
54    pub memory_usage: u64,
55    pub disk_usage: Option<u64>,
56    pub last_flush: Option<chrono::DateTime<chrono::Utc>>,
57}
58
59/// Storage factory for creating storage backends
60pub struct StorageFactory;
61
62impl StorageFactory {
63    /// Create a storage backend based on persistence mode
64    /// 
65    /// # Errors
66    /// Returns error if storage creation fails
67    pub async fn create(
68        mode: PersistenceMode,
69        data_dir: &str,
70        database_id: DatabaseId,
71    ) -> KVResult<Box<dyn Storage>> {
72        match mode {
73            PersistenceMode::Memory => {
74                Ok(Box::new(MemoryStorage::new()))
75            }
76            PersistenceMode::AOF => {
77                let aof_path = format!("{data_dir}/db_{database_id}.aof");
78                Ok(Box::new(AOFStorage::new(&aof_path).await?))
79            }
80            PersistenceMode::Full => {
81                let db_path = format!("{data_dir}/db_{database_id}");
82                Ok(Box::new(DiskStorage::new(&db_path)?))
83            }
84            PersistenceMode::Hybrid => {
85                // For hybrid mode, we'll use memory storage with AOF logging
86                let aof_path = format!("{data_dir}/db_{database_id}.aof");
87                Ok(Box::new(AOFStorage::new(&aof_path).await?))
88            }
89        }
90    }
91}
kv_core/storage/mod.rs

kv_core/storage/
mod.rs
