updb/tx/
mod.rs

1#![deny(unsafe_code)]
2
3use std::sync::Arc;
4
5use arc_swap::ArcSwap;
6use imbl::OrdMap;
7use tokio::sync::OwnedMutexGuard;
8
9use crate::error::Error;
10
11pub struct Tx<K, V> {
12    pub(crate) closed: bool,
13    pub(crate) writable: bool,
14    pub(crate) imm_data: OrdMap<K, V>,
15    pub(crate) lst_data: Arc<ArcSwap<OrdMap<K, V>>>,
16    pub(crate) writ_mux: Option<OwnedMutexGuard<()>>,
17}
18
19impl<K, V> Tx<K, V>
20where
21    K: Ord + Clone,
22    V: Eq + Clone,
23{
24    pub(crate) fn new(
25        data_ptr: Arc<ArcSwap<OrdMap<K, V>>>,
26        writable: bool,
27        guard: Option<OwnedMutexGuard<()>>,
28    ) -> Tx<K, V> {
29        Tx {
30            writable,
31            closed: false,
32            imm_data: (*(*data_ptr.load())).clone(),
33            lst_data: data_ptr.clone(),
34            writ_mux: guard,
35        }
36    }
37
38    pub fn closed(&self) -> bool {
39        self.closed
40    }
41
42    pub fn rollback(&mut self) -> Result<(), Error> {
43        if self.closed {
44            return Err(Error::TxClosed);
45        }
46
47        self.closed = true;
48
49        if let Some(lock) = &self.writ_mux.take() {
50            drop(lock);
51        }
52
53        Ok(())
54    }
55
56    pub fn commit(&mut self) -> Result<(), Error> {
57        if self.closed {
58            return Err(Error::TxClosed);
59        }
60
61        if !self.writable {
62            return Err(Error::TxNotWritable);
63        }
64
65        self.closed = true;
66
67        self.lst_data.store(Arc::new(self.imm_data.clone()));
68
69        if let Some(lock) = &self.writ_mux.take() {
70            drop(lock);
71        }
72
73        Ok(())
74    }
75
76    pub fn exists(&self, key: K) -> Result<bool, Error> {
77        if self.closed {
78            return Err(Error::TxClosed);
79        }
80
81        Ok(self.imm_data.contains_key(&key))
82    }
83
84    pub fn get(&self, key: K) -> Result<Option<V>, Error> {
85        if self.closed {
86            return Err(Error::TxClosed);
87        }
88
89        Ok(self.imm_data.get(&key).cloned())
90    }
91
92    pub fn set(&mut self, key: K, value: V) -> Result<(), Error> {
93        if self.closed {
94            return Err(Error::TxClosed);
95        }
96
97        if !self.writable {
98            return Err(Error::TxNotWritable);
99        }
100
101        self.imm_data.insert(key, value);
102
103        Ok(())
104    }
105
106    pub fn del(&mut self, key: K) -> Result<(), Error> {
107        if self.closed {
108            return Err(Error::TxClosed);
109        }
110
111        if !self.writable {
112            return Err(Error::TxNotWritable);
113        }
114
115        self.imm_data.remove(&key);
116
117        Ok(())
118    }
119}
updb/tx/mod.rs

updb/tx/
mod.rs
