kevy_embedded/
ops_atomic_all.rs

1//! Cross-shard read-modify-write closure:
2//! `Store::atomic_all_shards`.
3//!
4//! `atomic_all_shards(|tx| { ... })` holds a write lock on every
5//! shard for the closure body. Operations inside the closure are
6//! routed to their owning shards, and AOF writes are batched
7//! per-shard with one fsync per shard at commit time.
8//!
9//! Heavier than [`Store::atomic`](crate::Store::atomic): every
10//! reader and writer on the affected shards blocks until the
11//! closure returns. Use it only when the closure genuinely needs
12//! more than one shard and atomicity across them is required.
13
14use std::io;
15use std::sync::RwLockWriteGuard;
16
17use crate::shard::shard_idx;
18use crate::store::{Inner, Store, commit_write, store_err};
19
20#[cfg(not(target_arch = "wasm32"))]
21use crate::replica_glue::ensure_writable;
22
23#[cfg(target_arch = "wasm32")]
24fn ensure_writable(_s: &Store) -> io::Result<()> { Ok(()) }
25
26/// Context handed to the `atomic_all_shards` closure body. Methods
27/// route to the right shard by hashing the key.
28pub struct AtomicAllShards<'a> {
29    guards: Vec<RwLockWriteGuard<'a, Inner>>,
30    /// (shard_idx, serialised RESP-frame parts) queued for AOF commit.
31    log: Vec<(usize, Vec<Vec<u8>>)>,
32}
33
34impl<'a> AtomicAllShards<'a> {
35    fn idx(&self, key: &[u8]) -> usize {
36        shard_idx(key, self.guards.len())
37    }
38
39    fn log_arg(&mut self, idx: usize, parts: &[&[u8]]) {
40        self.log
41            .push((idx, parts.iter().map(|p| p.to_vec()).collect()));
42    }
43
44    // ---- string ops -----------------------------------------------
45
46    /// `SET key value` — always succeeds.
47    pub fn set(&mut self, key: &[u8], value: &[u8]) -> bool {
48        let i = self.idx(key);
49        let ok = self.guards[i]
50            .store
51            .set(key, value.to_vec(), None, false, false);
52        self.log_arg(i, &[b"SET", key, value]);
53        ok
54    }
55
56    /// `GET key`.
57    pub fn get(&mut self, key: &[u8]) -> io::Result<Option<Vec<u8>>> {
58        let i = self.idx(key);
59        self.guards[i]
60            .store
61            .get(key)
62            .map(|opt| opt.as_deref().map(<[u8]>::to_vec))
63            .map_err(store_err)
64    }
65
66    /// `INCR key`.
67    pub fn incr(&mut self, key: &[u8]) -> io::Result<i64> {
68        let i = self.idx(key);
69        let n = self.guards[i].store.incr_by(key, 1).map_err(store_err)?;
70        self.log_arg(i, &[b"INCR", key]);
71        Ok(n)
72    }
73
74    /// `INCRBY key delta`.
75    pub fn incr_by(&mut self, key: &[u8], delta: i64) -> io::Result<i64> {
76        let i = self.idx(key);
77        let n = self.guards[i].store.incr_by(key, delta).map_err(store_err)?;
78        let s = format!("{delta}");
79        self.log_arg(i, &[b"INCRBY", key, s.as_bytes()]);
80        Ok(n)
81    }
82
83    // ---- hash ops --------------------------------------------------
84
85    /// `HSET key field value [field value ...]`. Returns count newly
86    /// added (existing fields are overwritten but not counted).
87    pub fn hset(&mut self, key: &[u8], pairs: &[(&[u8], &[u8])]) -> io::Result<usize> {
88        let i = self.idx(key);
89        let owned: Vec<(Vec<u8>, Vec<u8>)> = pairs
90            .iter()
91            .map(|(f, v)| (f.to_vec(), v.to_vec()))
92            .collect();
93        let n = self.guards[i]
94            .store
95            .hset(key, &owned)
96            .map_err(store_err)?;
97        let mut parts: Vec<&[u8]> = Vec::with_capacity(2 + pairs.len() * 2);
98        parts.push(b"HSET");
99        parts.push(key);
100        for (f, v) in pairs {
101            parts.push(f);
102            parts.push(v);
103        }
104        self.log_arg(i, &parts);
105        Ok(n)
106    }
107
108    /// `HGET key field` — `None` when the key or field is absent.
109    pub fn hget(&mut self, key: &[u8], field: &[u8]) -> io::Result<Option<Vec<u8>>> {
110        let i = self.idx(key);
111        Ok(self.guards[i]
112            .store
113            .hget(key, field)
114            .map_err(store_err)?
115            .map(<[u8]>::to_vec))
116    }
117
118    /// `HINCRBY key field delta` — returns the field's new value.
119    pub fn hincrby(&mut self, key: &[u8], field: &[u8], delta: i64) -> io::Result<i64> {
120        let i = self.idx(key);
121        let n = self.guards[i]
122            .store
123            .hincrby(key, field, delta)
124            .map_err(store_err)?;
125        let s = format!("{delta}");
126        self.log_arg(i, &[b"HINCRBY", key, field, s.as_bytes()]);
127        Ok(n)
128    }
129
130    // ---- zset ops --------------------------------------------------
131
132    /// `ZADD key score member [score member ...]`. Returns count newly
133    /// added (score updates of existing members are not counted).
134    pub fn zadd(&mut self, key: &[u8], pairs: &[(f64, &[u8])]) -> io::Result<usize> {
135        let i = self.idx(key);
136        let owned: Vec<(f64, Vec<u8>)> =
137            pairs.iter().map(|(s, m)| (*s, m.to_vec())).collect();
138        let n = self.guards[i]
139            .store
140            .zadd(key, &owned)
141            .map_err(store_err)?;
142        let score_strs: Vec<Vec<u8>> = pairs
143            .iter()
144            .map(|(s, _)| format!("{s}").into_bytes())
145            .collect();
146        let mut parts: Vec<&[u8]> = Vec::with_capacity(2 + pairs.len() * 2);
147        parts.push(b"ZADD");
148        parts.push(key);
149        for (j, (_, m)) in pairs.iter().enumerate() {
150            parts.push(&score_strs[j]);
151            parts.push(m);
152        }
153        self.log_arg(i, &parts);
154        Ok(n)
155    }
156
157    /// `ZINCRBY key delta member` — returns the member's new score.
158    pub fn zincrby(&mut self, key: &[u8], delta: f64, member: &[u8]) -> io::Result<f64> {
159        let i = self.idx(key);
160        let n = self.guards[i]
161            .store
162            .zincrby(key, delta, member)
163            .map_err(store_err)?;
164        let s = format!("{delta}");
165        self.log_arg(i, &[b"ZINCRBY", key, s.as_bytes(), member]);
166        Ok(n)
167    }
168
169    /// `ZSCORE key member` (v2.1: parity with [`super::ops_atomic::AtomicCtx`]).
170    pub fn zscore(&mut self, key: &[u8], member: &[u8]) -> io::Result<Option<f64>> {
171        let i = self.idx(key);
172        self.guards[i].store.zscore(key, member).map_err(store_err)
173    }
174
175    // ---- keyspace ops (v2.1 — Pipeline write parity) ---------------
176
177    /// `DEL key [key ...]` — keys may span shards; each key's delete
178    /// is applied and AOF-logged on its own shard.
179    pub fn del(&mut self, keys: &[&[u8]]) -> usize {
180        let mut n = 0;
181        for k in keys {
182            let i = self.idx(k);
183            if self.guards[i].store.del_borrowed(&[k]) > 0 {
184                n += 1;
185                self.log_arg(i, &[b"DEL", k]);
186            }
187        }
188        n
189    }
190
191    /// `EXISTS key [key ...]` — count of the given keys that exist.
192    pub fn exists(&mut self, keys: &[&[u8]]) -> usize {
193        keys.iter()
194            .filter(|k| {
195                let i = self.idx(k);
196                self.guards[i].store.key_exists(k)
197            })
198            .count()
199    }
200
201    // ---- hash ops --------------------------------------------------
202
203    /// `HDEL key field [field ...]`.
204    pub fn hdel(&mut self, key: &[u8], fields: &[&[u8]]) -> io::Result<usize> {
205        let i = self.idx(key);
206        let owned: Vec<Vec<u8>> = fields.iter().map(|f| f.to_vec()).collect();
207        let removed = self.guards[i].store.hdel(key, &owned).map_err(store_err)?;
208        if removed > 0 {
209            let mut argv: Vec<&[u8]> = Vec::with_capacity(2 + fields.len());
210            argv.push(b"HDEL");
211            argv.push(key);
212            argv.extend_from_slice(fields);
213            self.log_arg(i, &argv);
214        }
215        Ok(removed)
216    }
217
218    /// `HGETALL key` — `(field, value)` pairs.
219    pub fn hgetall(&mut self, key: &[u8]) -> io::Result<Vec<(Vec<u8>, Vec<u8>)>> {
220        let i = self.idx(key);
221        let flat = self.guards[i].store.hgetall(key).map_err(store_err)?;
222        let mut out = Vec::with_capacity(flat.len() / 2);
223        let mut it = flat.into_iter();
224        while let (Some(f), Some(v)) = (it.next(), it.next()) {
225            out.push((f, v));
226        }
227        Ok(out)
228    }
229
230    /// `HMGET key field [field ...]` — `None` per absent field.
231    pub fn hmget(&mut self, key: &[u8], fields: &[&[u8]]) -> io::Result<Vec<Option<Vec<u8>>>> {
232        let i = self.idx(key);
233        self.guards[i].store.hmget_borrowed(key, fields).map_err(store_err)
234    }
235
236    /// `HEXISTS key field`.
237    pub fn hexists(&mut self, key: &[u8], field: &[u8]) -> io::Result<bool> {
238        let i = self.idx(key);
239        self.guards[i].store.hexists(key, field).map_err(store_err)
240    }
241
242    // ---- set ops ---------------------------------------------------
243
244    /// `SADD key member [member ...]`.
245    pub fn sadd(&mut self, key: &[u8], members: &[&[u8]]) -> io::Result<usize> {
246        let i = self.idx(key);
247        let owned: Vec<Vec<u8>> = members.iter().map(|m| m.to_vec()).collect();
248        let added = self.guards[i].store.sadd(key, &owned).map_err(store_err)?;
249        if added > 0 {
250            let mut argv: Vec<&[u8]> = Vec::with_capacity(2 + members.len());
251            argv.push(b"SADD");
252            argv.push(key);
253            argv.extend_from_slice(members);
254            self.log_arg(i, &argv);
255        }
256        Ok(added)
257    }
258
259    /// `SREM key member [member ...]`.
260    pub fn srem(&mut self, key: &[u8], members: &[&[u8]]) -> io::Result<usize> {
261        let i = self.idx(key);
262        let owned: Vec<Vec<u8>> = members.iter().map(|m| m.to_vec()).collect();
263        let removed = self.guards[i].store.srem(key, &owned).map_err(store_err)?;
264        if removed > 0 {
265            let mut argv: Vec<&[u8]> = Vec::with_capacity(2 + members.len());
266            argv.push(b"SREM");
267            argv.push(key);
268            argv.extend_from_slice(members);
269            self.log_arg(i, &argv);
270        }
271        Ok(removed)
272    }
273
274    // ---- list ops --------------------------------------------------
275
276    /// `LPUSH key value [value ...]` — returns the new list length.
277    pub fn lpush(&mut self, key: &[u8], values: &[&[u8]]) -> io::Result<usize> {
278        let i = self.idx(key);
279        let owned: Vec<Vec<u8>> = values.iter().map(|v| v.to_vec()).collect();
280        let len = self.guards[i].store.lpush(key, &owned).map_err(store_err)?;
281        let mut argv: Vec<&[u8]> = Vec::with_capacity(2 + values.len());
282        argv.push(b"LPUSH");
283        argv.push(key);
284        argv.extend_from_slice(values);
285        self.log_arg(i, &argv);
286        Ok(len)
287    }
288
289    /// `RPUSH key value [value ...]` — returns the new list length.
290    pub fn rpush(&mut self, key: &[u8], values: &[&[u8]]) -> io::Result<usize> {
291        let i = self.idx(key);
292        let owned: Vec<Vec<u8>> = values.iter().map(|v| v.to_vec()).collect();
293        let len = self.guards[i].store.rpush(key, &owned).map_err(store_err)?;
294        let mut argv: Vec<&[u8]> = Vec::with_capacity(2 + values.len());
295        argv.push(b"RPUSH");
296        argv.push(key);
297        argv.extend_from_slice(values);
298        self.log_arg(i, &argv);
299        Ok(len)
300    }
301
302    // ---- zset ops --------------------------------------------------
303
304    /// `ZREM key member [member ...]`.
305    pub fn zrem(&mut self, key: &[u8], members: &[&[u8]]) -> io::Result<usize> {
306        let i = self.idx(key);
307        let owned: Vec<Vec<u8>> = members.iter().map(|m| m.to_vec()).collect();
308        let removed = self.guards[i].store.zrem(key, &owned).map_err(store_err)?;
309        if removed > 0 {
310            let mut argv: Vec<&[u8]> = Vec::with_capacity(2 + members.len());
311            argv.push(b"ZREM");
312            argv.push(key);
313            argv.extend_from_slice(members);
314            self.log_arg(i, &argv);
315        }
316        Ok(removed)
317    }
318
319    /// `ZCARD key` — member count; 0 when absent.
320    pub fn zcard(&mut self, key: &[u8]) -> io::Result<usize> {
321        let i = self.idx(key);
322        self.guards[i].store.zcard(key).map_err(store_err)
323    }
324
325    /// Flags-aware `ZADD` (v2.1). AOF logs the applied pairs as plain
326    /// `ZADD` — the effect, never the condition (deterministic replay).
327    pub fn zadd_flags(
328        &mut self,
329        key: &[u8],
330        pairs: &[(f64, &[u8])],
331        flags: kevy_store::ZaddFlags,
332    ) -> io::Result<kevy_store::ZaddReport> {
333        if !flags.valid() {
334            return Err(io::Error::new(io::ErrorKind::InvalidInput, "invalid ZADD flag combo"));
335        }
336        let i = self.idx(key);
337        let rep = self.guards[i]
338            .store
339            .zadd_flags_borrowed(key, pairs, flags)
340            .map_err(store_err)?;
341        if !rep.applied.is_empty() {
342            let score_strs: Vec<Vec<u8>> = rep
343                .applied
344                .iter()
345                .map(|(s, _)| format!("{s}").into_bytes())
346                .collect();
347            let mut parts: Vec<&[u8]> = Vec::with_capacity(2 + rep.applied.len() * 2);
348            parts.push(b"ZADD");
349            parts.push(key);
350            for (j, (_, m)) in rep.applied.iter().enumerate() {
351                parts.push(&score_strs[j]);
352                parts.push(m);
353            }
354            self.log_arg(i, &parts);
355        }
356        Ok(rep)
357    }
358}
359
360impl Store {
361    /// Run `body` as a transaction holding write locks on EVERY
362    /// shard for the closure's duration. Reads inside the closure
363    /// see prior writes (full read-modify-write). On closure
364    /// return, AOF writes commit with one fsync per shard.
365    ///
366    /// Cost: blocks every other writer + reader on this Store for
367    /// the closure body. Use when atomic multi-shard semantics are
368    /// required; otherwise prefer the single-shard `atomic`.
369    pub fn atomic_all_shards<R>(
370        &self,
371        body: impl FnOnce(&mut AtomicAllShards<'_>) -> io::Result<R>,
372    ) -> io::Result<R> {
373        ensure_writable(self)?;
374        // Take every shard's write lock in shard-index order
375        // (deterministic order avoids deadlock).
376        let guards: Vec<RwLockWriteGuard<'_, Inner>> = self
377            .shards
378            .iter()
379            .map(|s| s.write().expect("lock poisoned"))
380            .collect();
381        let mut ctx = AtomicAllShards { guards, log: Vec::new() };
382        let r = body(&mut ctx)?;
383        // Commit AOF entries per-shard.
384        let log = std::mem::take(&mut ctx.log);
385        for (idx, parts) in log {
386            let g = &mut ctx.guards[idx];
387            let refs: Vec<&[u8]> = parts.iter().map(|v| v.as_slice()).collect();
388            commit_write(g, &refs)?;
389        }
390        Ok(r)
391    }
392}
393
394/// Parity manifest (v2.1): command names `AtomicAllShards` implements.
395/// MUST stay identical to `ops_atomic::ATOMIC_OPS` (the two ctxs
396/// drifted before — zscore was missing here).
397#[cfg_attr(not(test), allow(dead_code))]
398pub(crate) const ATOMIC_ALL_OPS: &[&str] = &[
399    "SET", "GET", "INCR", "INCRBY", "HSET", "HGET", "HINCRBY", "ZADD",
400    "ZINCRBY", "ZSCORE", "DEL", "EXISTS", "HDEL", "HGETALL", "HMGET",
401    "HEXISTS", "SADD", "SREM", "LPUSH", "RPUSH", "ZREM", "ZCARD",
402];
kevy_embedded/ops_atomic_all.rs

kevy_embedded/
ops_atomic_all.rs
