trueno_db/kv/
memory.rs

1//! In-memory KV store implementation using `DashMap`.
2//!
3//! This is the default backend - data is lost on process restart.
4//! For persistence, use `ParquetKvStore` (future).
5
6use super::KvStore;
7use crate::Result;
8use dashmap::DashMap;
9
10/// In-memory key-value store using lock-free concurrent hashmap.
11///
12/// Thread-safe and optimized for high-concurrency read/write workloads.
13/// Uses `DashMap` internally for O(1) average-case operations.
14///
15/// # Example
16///
17/// ```rust
18/// use trueno_db::kv::{KvStore, MemoryKvStore};
19///
20/// # async fn example() -> trueno_db::Result<()> {
21/// let store = MemoryKvStore::new();
22/// store.set("hello", b"world".to_vec()).await?;
23/// assert_eq!(store.get("hello").await?, Some(b"world".to_vec()));
24/// # Ok(())
25/// # }
26/// ```
27pub struct MemoryKvStore {
28    store: DashMap<String, Vec<u8>>,
29}
30
31impl MemoryKvStore {
32    /// Create a new in-memory KV store.
33    #[must_use]
34    pub fn new() -> Self {
35        Self { store: DashMap::new() }
36    }
37
38    /// Create with pre-allocated capacity.
39    #[must_use]
40    pub fn with_capacity(capacity: usize) -> Self {
41        Self { store: DashMap::with_capacity(capacity) }
42    }
43
44    /// Get the number of entries in the store.
45    #[must_use]
46    pub fn len(&self) -> usize {
47        self.store.len()
48    }
49
50    /// Check if the store is empty.
51    #[must_use]
52    pub fn is_empty(&self) -> bool {
53        self.store.is_empty()
54    }
55
56    /// Clear all entries.
57    pub fn clear(&self) {
58        self.store.clear();
59    }
60}
61
62impl Default for MemoryKvStore {
63    fn default() -> Self {
64        Self::new()
65    }
66}
67
68impl KvStore for MemoryKvStore {
69    async fn get(&self, key: &str) -> Result<Option<Vec<u8>>> {
70        Ok(self.store.get(key).map(|v| v.value().clone()))
71    }
72
73    async fn set(&self, key: &str, value: Vec<u8>) -> Result<()> {
74        self.store.insert(key.to_string(), value);
75        Ok(())
76    }
77
78    async fn delete(&self, key: &str) -> Result<()> {
79        self.store.remove(key);
80        Ok(())
81    }
82
83    async fn exists(&self, key: &str) -> Result<bool> {
84        Ok(self.store.contains_key(key))
85    }
86}
trueno_db/kv/memory.rs

trueno_db/kv/
memory.rs
