icydb_core/db/
registry.rs

1//! Module: db::registry
2//! Responsibility: thread-local store registry lifecycle and lookup authority.
3//! Does not own: store encode/decode semantics or query/executor planning behavior.
4//! Boundary: manages registry state for named data/index stores and typed registry errors.
5
6use crate::{
7    db::{data::DataStore, index::IndexStore},
8    error::{ErrorClass, ErrorOrigin, InternalError},
9};
10use std::{cell::RefCell, thread::LocalKey};
11use thiserror::Error as ThisError;
12
13///
14/// StoreRegistryError
15///
16
17#[derive(Debug, ThisError)]
18#[expect(clippy::enum_variant_names)]
19pub enum StoreRegistryError {
20    #[error("store '{0}' not found")]
21    StoreNotFound(String),
22
23    #[error("store '{0}' already registered")]
24    StoreAlreadyRegistered(String),
25
26    #[error(
27        "store '{name}' reuses the same row/index store pair already registered as '{existing_name}'"
28    )]
29    StoreHandlePairAlreadyRegistered { name: String, existing_name: String },
30}
31
32impl StoreRegistryError {
33    pub(crate) const fn class(&self) -> ErrorClass {
34        match self {
35            Self::StoreNotFound(_) => ErrorClass::Internal,
36            Self::StoreAlreadyRegistered(_) | Self::StoreHandlePairAlreadyRegistered { .. } => {
37                ErrorClass::InvariantViolation
38            }
39        }
40    }
41}
42
43impl From<StoreRegistryError> for InternalError {
44    fn from(err: StoreRegistryError) -> Self {
45        Self::classified(err.class(), ErrorOrigin::Store, err.to_string())
46    }
47}
48
49///
50/// StoreHandle
51/// Bound pair of row and index stores for one schema `Store` path.
52///
53
54#[derive(Clone, Copy, Debug)]
55pub struct StoreHandle {
56    data: &'static LocalKey<RefCell<DataStore>>,
57    index: &'static LocalKey<RefCell<IndexStore>>,
58}
59
60impl StoreHandle {
61    /// Build a store handle from thread-local row/index stores.
62    #[must_use]
63    pub const fn new(
64        data: &'static LocalKey<RefCell<DataStore>>,
65        index: &'static LocalKey<RefCell<IndexStore>>,
66    ) -> Self {
67        Self { data, index }
68    }
69
70    /// Borrow the row store immutably.
71    pub fn with_data<R>(&self, f: impl FnOnce(&DataStore) -> R) -> R {
72        self.data.with_borrow(f)
73    }
74
75    /// Borrow the row store mutably.
76    pub fn with_data_mut<R>(&self, f: impl FnOnce(&mut DataStore) -> R) -> R {
77        self.data.with_borrow_mut(f)
78    }
79
80    /// Borrow the index store immutably.
81    pub fn with_index<R>(&self, f: impl FnOnce(&IndexStore) -> R) -> R {
82        self.index.with_borrow(f)
83    }
84
85    /// Borrow the index store mutably.
86    pub fn with_index_mut<R>(&self, f: impl FnOnce(&mut IndexStore) -> R) -> R {
87        self.index.with_borrow_mut(f)
88    }
89
90    /// Return whether this store pair currently carries a synchronized
91    /// secondary covering-authority witness.
92    #[must_use]
93    pub(in crate::db) fn secondary_covering_authoritative(&self) -> bool {
94        self.with_data(DataStore::secondary_covering_authoritative)
95            && self.with_index(IndexStore::secondary_covering_authoritative)
96    }
97
98    /// Mark this row/index store pair as synchronized for witness-backed
99    /// secondary covering after successful commit or recovery.
100    pub(in crate::db) fn mark_secondary_covering_authoritative(&self) {
101        self.with_data_mut(DataStore::mark_secondary_covering_authoritative);
102        self.with_index_mut(IndexStore::mark_secondary_covering_authoritative);
103    }
104
105    /// Return the raw row-store accessor.
106    #[must_use]
107    pub const fn data_store(&self) -> &'static LocalKey<RefCell<DataStore>> {
108        self.data
109    }
110
111    /// Return the raw index-store accessor.
112    #[must_use]
113    pub const fn index_store(&self) -> &'static LocalKey<RefCell<IndexStore>> {
114        self.index
115    }
116}
117
118///
119/// StoreRegistry
120/// Thread-local registry for both row and index stores.
121///
122
123#[derive(Default)]
124pub struct StoreRegistry {
125    stores: Vec<(&'static str, StoreHandle)>,
126}
127
128impl StoreRegistry {
129    /// Create an empty store registry.
130    #[must_use]
131    pub fn new() -> Self {
132        Self::default()
133    }
134
135    /// Iterate registered stores.
136    ///
137    /// Iteration order follows registration order. Semantic result ordering
138    /// must still not depend on this iteration order; callers that need
139    /// deterministic ordering must sort by store path.
140    pub fn iter(&self) -> impl Iterator<Item = (&'static str, StoreHandle)> {
141        self.stores.iter().copied()
142    }
143
144    /// Register a `Store` path to its row/index store pair.
145    pub fn register_store(
146        &mut self,
147        name: &'static str,
148        data: &'static LocalKey<RefCell<DataStore>>,
149        index: &'static LocalKey<RefCell<IndexStore>>,
150    ) -> Result<(), InternalError> {
151        if self
152            .stores
153            .iter()
154            .any(|(existing_name, _)| *existing_name == name)
155        {
156            return Err(StoreRegistryError::StoreAlreadyRegistered(name.to_string()).into());
157        }
158
159        // Keep one canonical logical store name per physical row/index store pair.
160        if let Some(existing_name) =
161            self.stores
162                .iter()
163                .find_map(|(existing_name, existing_handle)| {
164                    (std::ptr::eq(existing_handle.data_store(), data)
165                        && std::ptr::eq(existing_handle.index_store(), index))
166                    .then_some(*existing_name)
167                })
168        {
169            return Err(StoreRegistryError::StoreHandlePairAlreadyRegistered {
170                name: name.to_string(),
171                existing_name: existing_name.to_string(),
172            }
173            .into());
174        }
175
176        self.stores.push((name, StoreHandle::new(data, index)));
177
178        Ok(())
179    }
180
181    /// Look up a store handle by path.
182    pub fn try_get_store(&self, path: &str) -> Result<StoreHandle, InternalError> {
183        self.stores
184            .iter()
185            .find_map(|(existing_path, handle)| (*existing_path == path).then_some(*handle))
186            .ok_or_else(|| StoreRegistryError::StoreNotFound(path.to_string()).into())
187    }
188}
189
190///
191/// TESTS
192///
193
194#[cfg(test)]
195mod tests {
196    use crate::{
197        db::{data::DataStore, index::IndexStore, registry::StoreRegistry},
198        error::{ErrorClass, ErrorOrigin},
199        testing::test_memory,
200    };
201    use std::{cell::RefCell, ptr};
202
203    const STORE_PATH: &str = "store_registry_tests::Store";
204    const ALIAS_STORE_PATH: &str = "store_registry_tests::StoreAlias";
205
206    thread_local! {
207        static TEST_DATA_STORE: RefCell<DataStore> = RefCell::new(DataStore::init(test_memory(151)));
208        static TEST_INDEX_STORE: RefCell<IndexStore> =
209            RefCell::new(IndexStore::init(test_memory(152)));
210    }
211
212    fn test_registry() -> StoreRegistry {
213        let mut registry = StoreRegistry::new();
214        registry
215            .register_store(STORE_PATH, &TEST_DATA_STORE, &TEST_INDEX_STORE)
216            .expect("test store registration should succeed");
217        registry
218    }
219
220    #[test]
221    fn register_store_binds_data_and_index_handles() {
222        let registry = test_registry();
223        let handle = registry
224            .try_get_store(STORE_PATH)
225            .expect("registered store path should resolve");
226
227        assert!(
228            ptr::eq(handle.data_store(), &TEST_DATA_STORE),
229            "store handle should expose the registered data store accessor"
230        );
231        assert!(
232            ptr::eq(handle.index_store(), &TEST_INDEX_STORE),
233            "store handle should expose the registered index store accessor"
234        );
235
236        let data_rows = handle.with_data(|store| store.len());
237        let index_rows = handle.with_index(IndexStore::len);
238        assert_eq!(data_rows, 0, "fresh test data store should be empty");
239        assert_eq!(index_rows, 0, "fresh test index store should be empty");
240    }
241
242    #[test]
243    fn missing_store_path_rejected_before_access() {
244        let registry = StoreRegistry::new();
245        let err = registry
246            .try_get_store("store_registry_tests::Missing")
247            .expect_err("missing path should fail lookup");
248
249        assert_eq!(err.class, ErrorClass::Internal);
250        assert_eq!(err.origin, ErrorOrigin::Store);
251        assert!(
252            err.message
253                .contains("store 'store_registry_tests::Missing' not found"),
254            "missing store lookup should include the missing path"
255        );
256    }
257
258    #[test]
259    fn duplicate_store_registration_is_rejected() {
260        let mut registry = StoreRegistry::new();
261        registry
262            .register_store(STORE_PATH, &TEST_DATA_STORE, &TEST_INDEX_STORE)
263            .expect("initial store registration should succeed");
264
265        let err = registry
266            .register_store(STORE_PATH, &TEST_DATA_STORE, &TEST_INDEX_STORE)
267            .expect_err("duplicate registration should fail");
268        assert_eq!(err.class, ErrorClass::InvariantViolation);
269        assert_eq!(err.origin, ErrorOrigin::Store);
270        assert!(
271            err.message
272                .contains("store 'store_registry_tests::Store' already registered"),
273            "duplicate registration should include the conflicting path"
274        );
275    }
276
277    #[test]
278    fn alias_store_registration_reusing_same_store_pair_is_rejected() {
279        let mut registry = StoreRegistry::new();
280        registry
281            .register_store(STORE_PATH, &TEST_DATA_STORE, &TEST_INDEX_STORE)
282            .expect("initial store registration should succeed");
283
284        let err = registry
285            .register_store(ALIAS_STORE_PATH, &TEST_DATA_STORE, &TEST_INDEX_STORE)
286            .expect_err("alias registration reusing the same store pair should fail");
287        assert_eq!(err.class, ErrorClass::InvariantViolation);
288        assert_eq!(err.origin, ErrorOrigin::Store);
289        assert!(
290            err.message.contains(
291                "store 'store_registry_tests::StoreAlias' reuses the same row/index store pair"
292            ),
293            "alias registration should include conflicting alias path"
294        );
295        assert!(
296            err.message
297                .contains("registered as 'store_registry_tests::Store'"),
298            "alias registration should include original path"
299        );
300    }
301}
icydb_core/db/registry.rs

icydb_core/db/
registry.rs
