vibesql_storage/database/
transaction_api.rs

1// ============================================================================
2// Transaction Management API
3// ============================================================================
4//
5// This module provides transaction management methods for the Database struct.
6// Methods are implemented via an impl block on the Database type.
7
8use super::transactions::TransactionChange;
9use super::Database;
10use crate::wal::{DurabilityMode, TransactionDurability, WalOp};
11use crate::StorageError;
12
13impl Database {
14    // ============================================================================
15    // Transaction Management
16    // ============================================================================
17
18    /// Record a change in the current transaction (if any)
19    pub fn record_change(&mut self, change: TransactionChange) {
20        self.lifecycle.transaction_manager_mut().record_change(change);
21    }
22
23    /// Begin a new transaction
24    pub fn begin_transaction(&mut self) -> Result<(), StorageError> {
25        self.begin_transaction_with_durability(TransactionDurability::Default)
26    }
27
28    /// Begin a new transaction with a specific durability hint
29    ///
30    /// The durability hint controls how the transaction's changes are persisted.
31    /// See [`TransactionDurability`] for available options.
32    pub fn begin_transaction_with_durability(
33        &mut self,
34        durability: TransactionDurability,
35    ) -> Result<(), StorageError> {
36        let catalog = &self.catalog.clone();
37        self.lifecycle.transaction_manager_mut().begin_transaction_with_durability(
38            catalog,
39            &self.tables,
40            durability,
41        )?;
42
43        // Emit WAL entry for persistence
44        if let Some(txn_id) = self.transaction_id() {
45            self.emit_wal_op(WalOp::TxnBegin { txn_id });
46        }
47
48        Ok(())
49    }
50
51    /// Commit the current transaction
52    pub fn commit_transaction(&mut self) -> Result<(), StorageError> {
53        // Get transaction ID and durability hint before committing (they will be cleared after)
54        let txn_id = self.transaction_id();
55        let durability_hint = self.lifecycle.transaction_manager().get_durability();
56
57        self.lifecycle.transaction_manager_mut().commit_transaction()?;
58
59        // Emit WAL entry for persistence
60        if let Some(txn_id) = txn_id {
61            self.emit_wal_op(WalOp::TxnCommit { txn_id });
62        }
63
64        // Apply durability-based sync at commit time
65        if let Some(hint) = durability_hint {
66            let db_mode = self
67                .persistence_engine
68                .as_ref()
69                .map(|e| e.durability_mode())
70                .unwrap_or(DurabilityMode::Lazy);
71
72            let resolved_mode = hint.resolve(db_mode);
73            if resolved_mode.sync_on_commit() {
74                self.sync_persistence()?;
75            }
76        }
77
78        Ok(())
79    }
80
81    /// Rollback the current transaction
82    pub fn rollback_transaction(&mut self) -> Result<(), StorageError> {
83        // Get transaction ID before rolling back (it will be cleared after)
84        let txn_id = self.transaction_id();
85
86        self.lifecycle.perform_rollback(&mut self.catalog, &mut self.tables)?;
87
88        // Emit WAL entry for persistence
89        if let Some(txn_id) = txn_id {
90            self.emit_wal_op(WalOp::TxnRollback { txn_id });
91        }
92
93        Ok(())
94    }
95
96    /// Check if we're currently in a transaction
97    pub fn in_transaction(&self) -> bool {
98        self.lifecycle.transaction_manager().in_transaction()
99    }
100
101    /// Get current transaction ID (for debugging)
102    pub fn transaction_id(&self) -> Option<u64> {
103        self.lifecycle.transaction_manager().transaction_id()
104    }
105
106    /// Create a savepoint within the current transaction
107    pub fn create_savepoint(&mut self, name: String) -> Result<(), StorageError> {
108        self.lifecycle.transaction_manager_mut().create_savepoint(name)
109    }
110
111    /// Rollback to a named savepoint
112    pub fn rollback_to_savepoint(&mut self, name: String) -> Result<(), StorageError> {
113        let changes_to_undo =
114            self.lifecycle.transaction_manager_mut().rollback_to_savepoint(name)?;
115
116        for change in changes_to_undo.into_iter().rev() {
117            self.undo_change(change)?;
118        }
119
120        Ok(())
121    }
122
123    /// Undo a single transaction change
124    fn undo_change(&mut self, change: TransactionChange) -> Result<(), StorageError> {
125        match change {
126            TransactionChange::Insert { table_name, row } => {
127                let table = self
128                    .get_table_mut(&table_name)
129                    .ok_or_else(|| StorageError::TableNotFound(table_name.clone()))?;
130                table.remove_row(&row)?;
131            }
132            TransactionChange::Update { table_name, old_row, new_row: _ } => {
133                let table = self
134                    .get_table_mut(&table_name)
135                    .ok_or_else(|| StorageError::TableNotFound(table_name.clone()))?;
136                table.remove_row(&old_row)?;
137                table.insert(old_row)?;
138            }
139            TransactionChange::Delete { table_name, row } => {
140                let table = self
141                    .get_table_mut(&table_name)
142                    .ok_or_else(|| StorageError::TableNotFound(table_name.clone()))?;
143                table.insert(row)?;
144            }
145        }
146        Ok(())
147    }
148
149    /// Release (destroy) a named savepoint
150    pub fn release_savepoint(&mut self, name: String) -> Result<(), StorageError> {
151        self.lifecycle.transaction_manager_mut().release_savepoint(name)
152    }
153}
vibesql_storage/database/transaction_api.rs

vibesql_storage/database/
transaction_api.rs
