1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
|
use super::Config;
use crate::Result;
use std::{future::Future, pin::Pin, sync::Arc};
#[cfg(feature = "sled")]
pub mod sled;
#[cfg(feature = "sqlite")]
pub mod sqlite;
#[cfg(feature = "heed")]
pub mod heed;
#[cfg(feature = "rocksdb")]
pub mod rocksdb;
#[cfg(feature = "persy")]
pub mod persy;
#[cfg(any(
feature = "sqlite",
feature = "rocksdb",
feature = "heed",
feature = "persy"
))]
pub mod watchers;
pub trait KeyValueDatabaseEngine: Send + Sync {
fn open(config: &Config) -> Result<Self>
where
Self: Sized;
fn open_tree(&self, name: &'static str) -> Result<Arc<dyn KvTree>>;
fn flush(&self) -> Result<()>;
fn cleanup(&self) -> Result<()> {
Ok(())
}
fn memory_usage(&self) -> Result<String> {
Ok("Current database engine does not support memory usage reporting.".to_owned())
}
fn clear_caches(&self) {}
}
pub trait KvTree: Send + Sync {
fn get(&self, key: &[u8]) -> Result<Option<Vec<u8>>>;
fn insert(&self, key: &[u8], value: &[u8]) -> Result<()>;
fn insert_batch(&self, iter: &mut dyn Iterator<Item = (Vec<u8>, Vec<u8>)>) -> Result<()>;
fn remove(&self, key: &[u8]) -> Result<()>;
fn iter<'a>(&'a self) -> Box<dyn Iterator<Item = (Vec<u8>, Vec<u8>)> + 'a>;
fn iter_from<'a>(
&'a self,
from: &[u8],
backwards: bool,
) -> Box<dyn Iterator<Item = (Vec<u8>, Vec<u8>)> + 'a>;
fn increment(&self, key: &[u8]) -> Result<Vec<u8>>;
fn increment_batch(&self, iter: &mut dyn Iterator<Item = Vec<u8>>) -> Result<()>;
fn scan_prefix<'a>(
&'a self,
prefix: Vec<u8>,
) -> Box<dyn Iterator<Item = (Vec<u8>, Vec<u8>)> + 'a>;
fn watch_prefix<'a>(&'a self, prefix: &[u8]) -> Pin<Box<dyn Future<Output = ()> + Send + 'a>>;
fn clear(&self) -> Result<()> {
for (key, _) in self.iter() {
self.remove(&key)?;
}
Ok(())
}
}
|
