risingwave_hummock_sdk/
key.rs

1// Copyright 2025 RisingWave Labs
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//     http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15use std::borrow::Borrow;
16use std::cmp::Ordering;
17use std::fmt::Debug;
18use std::iter::once;
19use std::ops::Bound::*;
20use std::ops::{Bound, Deref, DerefMut, RangeBounds};
21use std::ptr;
22
23use bytes::{Buf, BufMut, Bytes, BytesMut};
24use risingwave_common::catalog::TableId;
25use risingwave_common::hash::VirtualNode;
26use risingwave_common_estimate_size::EstimateSize;
27
28use crate::{EpochWithGap, HummockEpoch};
29
30pub const EPOCH_LEN: usize = std::mem::size_of::<HummockEpoch>();
31pub const TABLE_PREFIX_LEN: usize = std::mem::size_of::<u32>();
32// Max length for key overlap and diff length. See KeyPrefix::encode.
33pub const MAX_KEY_LEN: usize = u16::MAX as usize;
34
35pub type KeyPayloadType = Bytes;
36pub type TableKeyRange = (
37    Bound<TableKey<KeyPayloadType>>,
38    Bound<TableKey<KeyPayloadType>>,
39);
40pub type UserKeyRange = (
41    Bound<UserKey<KeyPayloadType>>,
42    Bound<UserKey<KeyPayloadType>>,
43);
44pub type UserKeyRangeRef<'a> = (Bound<UserKey<&'a [u8]>>, Bound<UserKey<&'a [u8]>>);
45pub type FullKeyRange = (
46    Bound<FullKey<KeyPayloadType>>,
47    Bound<FullKey<KeyPayloadType>>,
48);
49
50pub fn is_empty_key_range(key_range: &TableKeyRange) -> bool {
51    match key_range {
52        (Included(start), Excluded(end)) => start == end,
53        _ => false,
54    }
55}
56
57/// Returns left inclusive and right exclusive vnode index of the given range.
58///
59/// # Vnode count unawareness
60///
61/// Note that this function is not aware of the vnode count that is actually used in this table.
62/// For example, if the total vnode count is 256, `Unbounded` can be a correct end bound for vnode 255,
63/// but this function will still return `Excluded(256)`.
64///
65/// See also [`vnode`] and [`end_bound_of_vnode`] which hold such invariant.
66pub fn vnode_range(range: &TableKeyRange) -> (usize, usize) {
67    let (left, right) = range;
68    let left = match left {
69        Included(key) | Excluded(key) => key.vnode_part().to_index(),
70        Unbounded => 0,
71    };
72    let right = match right {
73        Included(key) => key.vnode_part().to_index() + 1,
74        Excluded(key) => {
75            let (vnode, inner_key) = key.split_vnode();
76            if inner_key.is_empty() {
77                // When the exclusive end key range contains only a vnode,
78                // the whole vnode is excluded.
79                vnode.to_index()
80            } else {
81                vnode.to_index() + 1
82            }
83        }
84        Unbounded => VirtualNode::MAX_REPRESENTABLE.to_index() + 1,
85    };
86    (left, right)
87}
88
89/// Ensure there is only one vnode involved in table key range and return the vnode.
90///
91/// # Vnode count unawareness
92///
93/// Note that this function is not aware of the vnode count that is actually used in this table.
94/// For example, if the total vnode count is 256, `Unbounded` can be a correct end bound for vnode 255,
95/// but this function will still require `Excluded(256)`.
96///
97/// See also [`vnode_range`] and [`end_bound_of_vnode`] which hold such invariant.
98pub fn vnode(range: &TableKeyRange) -> VirtualNode {
99    let (l, r_exclusive) = vnode_range(range);
100    assert_eq!(r_exclusive - l, 1);
101    VirtualNode::from_index(l)
102}
103
104/// Converts user key to full key by appending `epoch` to the user key.
105pub fn key_with_epoch(mut user_key: Vec<u8>, epoch: HummockEpoch) -> Vec<u8> {
106    let res = epoch.to_be();
107    user_key.reserve(EPOCH_LEN);
108    let buf = user_key.chunk_mut();
109
110    // TODO: check whether this hack improves performance
111    unsafe {
112        ptr::copy_nonoverlapping(
113            &res as *const _ as *const u8,
114            buf.as_mut_ptr() as *mut _,
115            EPOCH_LEN,
116        );
117        user_key.advance_mut(EPOCH_LEN);
118    }
119
120    user_key
121}
122
123/// Splits a full key into its user key part and epoch part.
124#[inline]
125pub fn split_key_epoch(full_key: &[u8]) -> (&[u8], &[u8]) {
126    let pos = full_key
127        .len()
128        .checked_sub(EPOCH_LEN)
129        .unwrap_or_else(|| panic!("bad full key format: {:?}", full_key));
130    full_key.split_at(pos)
131}
132
133/// Extract encoded [`UserKey`] from encoded [`FullKey`] without epoch part
134pub fn user_key(full_key: &[u8]) -> &[u8] {
135    split_key_epoch(full_key).0
136}
137
138/// Extract table key from encoded [`UserKey`] without table id part
139pub fn table_key(user_key: &[u8]) -> &[u8] {
140    &user_key[TABLE_PREFIX_LEN..]
141}
142
143#[inline(always)]
144/// Extract encoded [`UserKey`] from encoded [`FullKey`] but allow empty slice
145pub fn get_user_key(full_key: &[u8]) -> Vec<u8> {
146    if full_key.is_empty() {
147        vec![]
148    } else {
149        user_key(full_key).to_vec()
150    }
151}
152
153/// Extract table id from encoded [`FullKey`]
154#[inline(always)]
155pub fn get_table_id(full_key: &[u8]) -> u32 {
156    let mut buf = full_key;
157    buf.get_u32()
158}
159
160// Copyright 2016 TiKV Project Authors. Licensed under Apache-2.0.
161
162/// Computes the next key of the given key.
163///
164/// If the key has no successor key (e.g. the input is "\xff\xff"), the result
165/// would be an empty vector.
166///
167/// # Examples
168///
169/// ```rust
170/// use risingwave_hummock_sdk::key::next_key;
171/// assert_eq!(next_key(b"123"), b"124");
172/// assert_eq!(next_key(b"12\xff"), b"13");
173/// assert_eq!(next_key(b"\xff\xff"), b"");
174/// assert_eq!(next_key(b"\xff\xfe"), b"\xff\xff");
175/// assert_eq!(next_key(b"T"), b"U");
176/// assert_eq!(next_key(b""), b"");
177/// ```
178pub fn next_key(key: &[u8]) -> Vec<u8> {
179    if let Some((s, e)) = next_key_no_alloc(key) {
180        let mut res = Vec::with_capacity(s.len() + 1);
181        res.extend_from_slice(s);
182        res.push(e);
183        res
184    } else {
185        Vec::new()
186    }
187}
188
189/// Computes the previous key of the given key.
190///
191/// If the key has no predecessor key (e.g. the input is "\x00\x00"), the result
192/// would be a "\xff\xff" vector.
193///
194/// # Examples
195///
196/// ```rust
197/// use risingwave_hummock_sdk::key::prev_key;
198/// assert_eq!(prev_key(b"123"), b"122");
199/// assert_eq!(prev_key(b"12\x00"), b"11\xff");
200/// assert_eq!(prev_key(b"\x00\x00"), b"\xff\xff");
201/// assert_eq!(prev_key(b"\x00\x01"), b"\x00\x00");
202/// assert_eq!(prev_key(b"T"), b"S");
203/// assert_eq!(prev_key(b""), b"");
204/// ```
205pub fn prev_key(key: &[u8]) -> Vec<u8> {
206    let pos = key.iter().rposition(|b| *b != 0x00);
207    match pos {
208        Some(pos) => {
209            let mut res = Vec::with_capacity(key.len());
210            res.extend_from_slice(&key[0..pos]);
211            res.push(key[pos] - 1);
212            if pos + 1 < key.len() {
213                res.push(b"\xff".to_owned()[0]);
214            }
215            res
216        }
217        None => {
218            vec![0xff; key.len()]
219        }
220    }
221}
222
223fn next_key_no_alloc(key: &[u8]) -> Option<(&[u8], u8)> {
224    let pos = key.iter().rposition(|b| *b != 0xff)?;
225    Some((&key[..pos], key[pos] + 1))
226}
227
228// End Copyright 2016 TiKV Project Authors. Licensed under Apache-2.0.
229
230/// compute the next epoch, and don't change the bytes of the u8 slice.
231/// # Examples
232///
233/// ```rust
234/// use risingwave_hummock_sdk::key::next_epoch;
235/// assert_eq!(next_epoch(b"123"), b"124");
236/// assert_eq!(next_epoch(b"\xff\x00\xff"), b"\xff\x01\x00");
237/// assert_eq!(next_epoch(b"\xff\xff"), b"\x00\x00");
238/// assert_eq!(next_epoch(b"\x00\x00"), b"\x00\x01");
239/// assert_eq!(next_epoch(b"S"), b"T");
240/// assert_eq!(next_epoch(b""), b"");
241/// ```
242pub fn next_epoch(epoch: &[u8]) -> Vec<u8> {
243    let pos = epoch.iter().rposition(|b| *b != 0xff);
244    match pos {
245        Some(mut pos) => {
246            let mut res = Vec::with_capacity(epoch.len());
247            res.extend_from_slice(&epoch[0..pos]);
248            res.push(epoch[pos] + 1);
249            while pos + 1 < epoch.len() {
250                res.push(0x00);
251                pos += 1;
252            }
253            res
254        }
255        None => {
256            vec![0x00; epoch.len()]
257        }
258    }
259}
260
261/// compute the prev epoch, and don't change the bytes of the u8 slice.
262/// # Examples
263///
264/// ```rust
265/// use risingwave_hummock_sdk::key::prev_epoch;
266/// assert_eq!(prev_epoch(b"124"), b"123");
267/// assert_eq!(prev_epoch(b"\xff\x01\x00"), b"\xff\x00\xff");
268/// assert_eq!(prev_epoch(b"\x00\x00"), b"\xff\xff");
269/// assert_eq!(prev_epoch(b"\x00\x01"), b"\x00\x00");
270/// assert_eq!(prev_epoch(b"T"), b"S");
271/// assert_eq!(prev_epoch(b""), b"");
272/// ```
273pub fn prev_epoch(epoch: &[u8]) -> Vec<u8> {
274    let pos = epoch.iter().rposition(|b| *b != 0x00);
275    match pos {
276        Some(mut pos) => {
277            let mut res = Vec::with_capacity(epoch.len());
278            res.extend_from_slice(&epoch[0..pos]);
279            res.push(epoch[pos] - 1);
280            while pos + 1 < epoch.len() {
281                res.push(0xff);
282                pos += 1;
283            }
284            res
285        }
286        None => {
287            vec![0xff; epoch.len()]
288        }
289    }
290}
291
292/// compute the next full key of the given full key
293///
294/// if the `user_key` has no successor key, the result will be a empty vec
295pub fn next_full_key(full_key: &[u8]) -> Vec<u8> {
296    let (user_key, epoch) = split_key_epoch(full_key);
297    let prev_epoch = prev_epoch(epoch);
298    let mut res = Vec::with_capacity(full_key.len());
299    if prev_epoch.cmp(&vec![0xff; prev_epoch.len()]) == Ordering::Equal {
300        let next_user_key = next_key(user_key);
301        if next_user_key.is_empty() {
302            return Vec::new();
303        }
304        res.extend_from_slice(next_user_key.as_slice());
305        res.extend_from_slice(prev_epoch.as_slice());
306        res
307    } else {
308        res.extend_from_slice(user_key);
309        res.extend_from_slice(prev_epoch.as_slice());
310        res
311    }
312}
313
314/// compute the prev full key of the given full key
315///
316/// if the `user_key` has no predecessor key, the result will be a empty vec
317pub fn prev_full_key(full_key: &[u8]) -> Vec<u8> {
318    let (user_key, epoch) = split_key_epoch(full_key);
319    let next_epoch = next_epoch(epoch);
320    let mut res = Vec::with_capacity(full_key.len());
321    if next_epoch.cmp(&vec![0x00; next_epoch.len()]) == Ordering::Equal {
322        let prev_user_key = prev_key(user_key);
323        if prev_user_key.cmp(&vec![0xff; prev_user_key.len()]) == Ordering::Equal {
324            return Vec::new();
325        }
326        res.extend_from_slice(prev_user_key.as_slice());
327        res.extend_from_slice(next_epoch.as_slice());
328        res
329    } else {
330        res.extend_from_slice(user_key);
331        res.extend_from_slice(next_epoch.as_slice());
332        res
333    }
334}
335
336/// [`Unbounded`] if the vnode is the maximum representable value (i.e. [`VirtualNode::MAX_REPRESENTABLE`]),
337/// otherwise [`Excluded`] the next vnode.
338///
339/// Note that this function is not aware of the vnode count that is actually used in this table.
340/// For example, if the total vnode count is 256, `Unbounded` can be a correct end bound for vnode 255,
341/// but this function will still return `Excluded(256)`. See also [`vnode`] and [`vnode_range`] which
342/// rely on such invariant.
343pub fn end_bound_of_vnode(vnode: VirtualNode) -> Bound<Bytes> {
344    if vnode == VirtualNode::MAX_REPRESENTABLE {
345        Unbounded
346    } else {
347        let end_bound_index = vnode.to_index() + 1;
348        Excluded(Bytes::copy_from_slice(
349            &VirtualNode::from_index(end_bound_index).to_be_bytes(),
350        ))
351    }
352}
353
354/// Get the end bound of the given `prefix` when transforming it to a key range.
355pub fn end_bound_of_prefix(prefix: &[u8]) -> Bound<Bytes> {
356    if let Some((s, e)) = next_key_no_alloc(prefix) {
357        let mut buf = BytesMut::with_capacity(s.len() + 1);
358        buf.extend_from_slice(s);
359        buf.put_u8(e);
360        Excluded(buf.freeze())
361    } else {
362        Unbounded
363    }
364}
365
366/// Get the start bound of the given `prefix` when it is excluded from the range.
367pub fn start_bound_of_excluded_prefix(prefix: &[u8]) -> Bound<Bytes> {
368    if let Some((s, e)) = next_key_no_alloc(prefix) {
369        let mut buf = BytesMut::with_capacity(s.len() + 1);
370        buf.extend_from_slice(s);
371        buf.put_u8(e);
372        Included(buf.freeze())
373    } else {
374        panic!("the prefix is the maximum value")
375    }
376}
377
378/// Transform the given `prefix` to a key range.
379pub fn range_of_prefix(prefix: &[u8]) -> (Bound<Bytes>, Bound<Bytes>) {
380    if prefix.is_empty() {
381        (Unbounded, Unbounded)
382    } else {
383        (
384            Included(Bytes::copy_from_slice(prefix)),
385            end_bound_of_prefix(prefix),
386        )
387    }
388}
389
390pub fn prefix_slice_with_vnode(vnode: VirtualNode, slice: &[u8]) -> Bytes {
391    let prefix = vnode.to_be_bytes();
392    let mut buf = BytesMut::with_capacity(prefix.len() + slice.len());
393    buf.extend_from_slice(&prefix);
394    buf.extend_from_slice(slice);
395    buf.freeze()
396}
397
398/// Prepend the `prefix` to the given key `range`.
399pub fn prefixed_range_with_vnode<B: AsRef<[u8]>>(
400    range: impl RangeBounds<B>,
401    vnode: VirtualNode,
402) -> TableKeyRange {
403    let prefixed = |b: &B| -> Bytes { prefix_slice_with_vnode(vnode, b.as_ref()) };
404
405    let start: Bound<Bytes> = match range.start_bound() {
406        Included(b) => Included(prefixed(b)),
407        Excluded(b) => {
408            assert!(!b.as_ref().is_empty());
409            Excluded(prefixed(b))
410        }
411        Unbounded => Included(Bytes::copy_from_slice(&vnode.to_be_bytes())),
412    };
413
414    let end = match range.end_bound() {
415        Included(b) => Included(prefixed(b)),
416        Excluded(b) => {
417            assert!(!b.as_ref().is_empty());
418            Excluded(prefixed(b))
419        }
420        Unbounded => end_bound_of_vnode(vnode),
421    };
422
423    map_table_key_range((start, end))
424}
425
426pub trait SetSlice<S: AsRef<[u8]> + ?Sized> {
427    fn set(&mut self, value: &S);
428}
429
430impl<S: AsRef<[u8]> + ?Sized> SetSlice<S> for Vec<u8> {
431    fn set(&mut self, value: &S) {
432        self.clear();
433        self.extend_from_slice(value.as_ref());
434    }
435}
436
437impl SetSlice<Bytes> for Bytes {
438    fn set(&mut self, value: &Bytes) {
439        *self = value.clone()
440    }
441}
442
443pub trait CopyFromSlice: Send + 'static {
444    fn copy_from_slice(slice: &[u8]) -> Self;
445}
446
447impl CopyFromSlice for Vec<u8> {
448    fn copy_from_slice(slice: &[u8]) -> Self {
449        Vec::from(slice)
450    }
451}
452
453impl CopyFromSlice for Bytes {
454    fn copy_from_slice(slice: &[u8]) -> Self {
455        Bytes::copy_from_slice(slice)
456    }
457}
458
459impl CopyFromSlice for () {
460    fn copy_from_slice(_: &[u8]) -> Self {}
461}
462
463/// [`TableKey`] is an internal concept in storage. It's a wrapper around the key directly from the
464/// user, to make the code clearer and avoid confusion with encoded [`UserKey`] and [`FullKey`].
465///
466/// Its name come from the assumption that Hummock is always accessed by a table-like structure
467/// identified by a [`TableId`].
468#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Default)]
469pub struct TableKey<T: AsRef<[u8]>>(pub T);
470
471impl<T: AsRef<[u8]>> Debug for TableKey<T> {
472    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
473        write!(f, "TableKey {{ {} }}", hex::encode(self.0.as_ref()))
474    }
475}
476
477impl<T: AsRef<[u8]>> Deref for TableKey<T> {
478    type Target = T;
479
480    fn deref(&self) -> &Self::Target {
481        &self.0
482    }
483}
484
485impl<T: AsRef<[u8]>> DerefMut for TableKey<T> {
486    fn deref_mut(&mut self) -> &mut Self::Target {
487        &mut self.0
488    }
489}
490
491impl<T: AsRef<[u8]>> AsRef<[u8]> for TableKey<T> {
492    fn as_ref(&self) -> &[u8] {
493        self.0.as_ref()
494    }
495}
496
497impl TableKey<Bytes> {
498    pub fn split_vnode_bytes(&self) -> (VirtualNode, Bytes) {
499        debug_assert!(
500            self.0.len() >= VirtualNode::SIZE,
501            "too short table key: {:?}",
502            self.0.as_ref()
503        );
504        let (vnode, _) = self.0.split_first_chunk::<{ VirtualNode::SIZE }>().unwrap();
505        (
506            VirtualNode::from_be_bytes(*vnode),
507            self.0.slice(VirtualNode::SIZE..),
508        )
509    }
510}
511
512impl<T: AsRef<[u8]>> TableKey<T> {
513    pub fn split_vnode(&self) -> (VirtualNode, &[u8]) {
514        debug_assert!(
515            self.0.as_ref().len() >= VirtualNode::SIZE,
516            "too short table key: {:?}",
517            self.0.as_ref()
518        );
519        let (vnode, inner_key) = self
520            .0
521            .as_ref()
522            .split_first_chunk::<{ VirtualNode::SIZE }>()
523            .unwrap();
524        (VirtualNode::from_be_bytes(*vnode), inner_key)
525    }
526
527    pub fn vnode_part(&self) -> VirtualNode {
528        self.split_vnode().0
529    }
530
531    pub fn key_part(&self) -> &[u8] {
532        self.split_vnode().1
533    }
534
535    pub fn to_ref(&self) -> TableKey<&[u8]> {
536        TableKey(self.0.as_ref())
537    }
538}
539
540impl<T: AsRef<[u8]>> Borrow<[u8]> for TableKey<T> {
541    fn borrow(&self) -> &[u8] {
542        self.0.as_ref()
543    }
544}
545
546impl EstimateSize for TableKey<Bytes> {
547    fn estimated_heap_size(&self) -> usize {
548        self.0.estimated_heap_size()
549    }
550}
551
552impl TableKey<&[u8]> {
553    pub fn copy_into<T: CopyFromSlice + AsRef<[u8]>>(&self) -> TableKey<T> {
554        TableKey(T::copy_from_slice(self.as_ref()))
555    }
556}
557
558#[inline]
559pub fn map_table_key_range(range: (Bound<KeyPayloadType>, Bound<KeyPayloadType>)) -> TableKeyRange {
560    (range.0.map(TableKey), range.1.map(TableKey))
561}
562
563pub fn gen_key_from_bytes(vnode: VirtualNode, payload: &[u8]) -> TableKey<Bytes> {
564    TableKey(Bytes::from(
565        [vnode.to_be_bytes().as_slice(), payload].concat(),
566    ))
567}
568
569pub fn gen_key_from_str(vnode: VirtualNode, payload: &str) -> TableKey<Bytes> {
570    gen_key_from_bytes(vnode, payload.as_bytes())
571}
572
573/// [`UserKey`] is is an internal concept in storage. In the storage interface, user specifies
574/// `table_key` and `table_id` (in `ReadOptions` or `WriteOptions`) as the input. The storage
575/// will group these two values into one struct for convenient filtering.
576///
577/// The encoded format is | `table_id` | `table_key` |.
578#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Default)]
579pub struct UserKey<T: AsRef<[u8]>> {
580    // When comparing `UserKey`, we first compare `table_id`, then `table_key`. So the order of
581    // declaration matters.
582    pub table_id: TableId,
583    pub table_key: TableKey<T>,
584}
585
586impl<T: AsRef<[u8]>> Debug for UserKey<T> {
587    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
588        write!(f, "UserKey {{ {}, {:?} }}", self.table_id, self.table_key)
589    }
590}
591
592impl<T: AsRef<[u8]>> UserKey<T> {
593    pub fn new(table_id: TableId, table_key: TableKey<T>) -> Self {
594        Self {
595            table_id,
596            table_key,
597        }
598    }
599
600    /// Pass the inner type of `table_key` to make the code less verbose.
601    pub fn for_test(table_id: TableId, table_key: T) -> Self {
602        Self {
603            table_id,
604            table_key: TableKey(table_key),
605        }
606    }
607
608    /// Encode in to a buffer.
609    pub fn encode_into(&self, buf: &mut impl BufMut) {
610        buf.put_u32(self.table_id.as_raw_id());
611        buf.put_slice(self.table_key.as_ref());
612    }
613
614    pub fn encode_table_key_into(&self, buf: &mut impl BufMut) {
615        buf.put_slice(self.table_key.as_ref());
616    }
617
618    pub fn encode(&self) -> Vec<u8> {
619        let mut ret = Vec::with_capacity(TABLE_PREFIX_LEN + self.table_key.as_ref().len());
620        self.encode_into(&mut ret);
621        ret
622    }
623
624    pub fn is_empty(&self) -> bool {
625        self.table_key.as_ref().is_empty()
626    }
627
628    /// Get the length of the encoded format.
629    pub fn encoded_len(&self) -> usize {
630        self.table_key.as_ref().len() + TABLE_PREFIX_LEN
631    }
632
633    pub fn get_vnode_id(&self) -> usize {
634        self.table_key.vnode_part().to_index()
635    }
636}
637
638impl<'a> UserKey<&'a [u8]> {
639    /// Construct a [`UserKey`] from a byte slice. Its `table_key` will be a part of the input
640    /// `slice`.
641    pub fn decode(slice: &'a [u8]) -> Self {
642        let table_id: u32 = (&slice[..]).get_u32();
643
644        Self {
645            table_id: TableId::new(table_id),
646            table_key: TableKey(&slice[TABLE_PREFIX_LEN..]),
647        }
648    }
649
650    pub fn to_vec(self) -> UserKey<Vec<u8>> {
651        self.copy_into()
652    }
653
654    pub fn copy_into<T: CopyFromSlice + AsRef<[u8]>>(self) -> UserKey<T> {
655        UserKey {
656            table_id: self.table_id,
657            table_key: TableKey(T::copy_from_slice(self.table_key.0)),
658        }
659    }
660}
661
662impl<T: AsRef<[u8]> + Clone> UserKey<&T> {
663    pub fn cloned(self) -> UserKey<T> {
664        UserKey {
665            table_id: self.table_id,
666            table_key: TableKey(self.table_key.0.clone()),
667        }
668    }
669}
670
671impl<T: AsRef<[u8]>> UserKey<T> {
672    pub fn as_ref(&self) -> UserKey<&[u8]> {
673        UserKey::new(self.table_id, TableKey(self.table_key.as_ref()))
674    }
675}
676
677impl<T: AsRef<[u8]>> UserKey<T> {
678    /// Use this method to override an old `UserKey<Vec<u8>>` with a `UserKey<&[u8]>` to own the
679    /// table key without reallocating a new `UserKey` object.
680    pub fn set<F>(&mut self, other: UserKey<F>)
681    where
682        T: SetSlice<F>,
683        F: AsRef<[u8]>,
684    {
685        self.table_id = other.table_id;
686        self.table_key.0.set(&other.table_key.0);
687    }
688}
689
690impl UserKey<Vec<u8>> {
691    pub fn into_bytes(self) -> UserKey<Bytes> {
692        UserKey {
693            table_id: self.table_id,
694            table_key: TableKey(Bytes::from(self.table_key.0)),
695        }
696    }
697}
698
699/// [`FullKey`] is an internal concept in storage. It associates [`UserKey`] with an epoch.
700///
701/// The encoded format is | `user_key` | `epoch` |.
702#[derive(Clone, Copy, PartialEq, Eq, Hash, Default)]
703pub struct FullKey<T: AsRef<[u8]>> {
704    pub user_key: UserKey<T>,
705    pub epoch_with_gap: EpochWithGap,
706}
707
708impl<T: AsRef<[u8]>> Debug for FullKey<T> {
709    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
710        write!(
711            f,
712            "FullKey {{ {:?}, epoch: {}, epoch_with_gap: {}, spill_offset: {}}}",
713            self.user_key,
714            self.epoch_with_gap.pure_epoch(),
715            self.epoch_with_gap.as_u64(),
716            self.epoch_with_gap.as_u64() - self.epoch_with_gap.pure_epoch(),
717        )
718    }
719}
720
721impl<T: AsRef<[u8]>> FullKey<T> {
722    pub fn new(table_id: TableId, table_key: TableKey<T>, epoch: HummockEpoch) -> Self {
723        Self {
724            user_key: UserKey::new(table_id, table_key),
725            epoch_with_gap: EpochWithGap::new(epoch, 0),
726        }
727    }
728
729    pub fn new_with_gap_epoch(
730        table_id: TableId,
731        table_key: TableKey<T>,
732        epoch_with_gap: EpochWithGap,
733    ) -> Self {
734        Self {
735            user_key: UserKey::new(table_id, table_key),
736            epoch_with_gap,
737        }
738    }
739
740    pub fn from_user_key(user_key: UserKey<T>, epoch: HummockEpoch) -> Self {
741        Self {
742            user_key,
743            epoch_with_gap: EpochWithGap::new_from_epoch(epoch),
744        }
745    }
746
747    /// Pass the inner type of `table_key` to make the code less verbose.
748    pub fn for_test(table_id: TableId, table_key: T, epoch: HummockEpoch) -> Self {
749        Self {
750            user_key: UserKey::for_test(table_id, table_key),
751            epoch_with_gap: EpochWithGap::new(epoch, 0),
752        }
753    }
754
755    /// Encode in to a buffer.
756    pub fn encode_into(&self, buf: &mut impl BufMut) {
757        self.user_key.encode_into(buf);
758        buf.put_u64(self.epoch_with_gap.as_u64());
759    }
760
761    pub fn encode(&self) -> Vec<u8> {
762        let mut buf = Vec::with_capacity(
763            TABLE_PREFIX_LEN + self.user_key.table_key.as_ref().len() + EPOCH_LEN,
764        );
765        self.encode_into(&mut buf);
766        buf
767    }
768
769    // Encode in to a buffer.
770    pub fn encode_into_without_table_id(&self, buf: &mut impl BufMut) {
771        self.user_key.encode_table_key_into(buf);
772        buf.put_u64(self.epoch_with_gap.as_u64());
773    }
774
775    pub fn encode_reverse_epoch(&self) -> Vec<u8> {
776        let mut buf = Vec::with_capacity(
777            TABLE_PREFIX_LEN + self.user_key.table_key.as_ref().len() + EPOCH_LEN,
778        );
779        self.user_key.encode_into(&mut buf);
780        buf.put_u64(u64::MAX - self.epoch_with_gap.as_u64());
781        buf
782    }
783
784    pub fn is_empty(&self) -> bool {
785        self.user_key.is_empty()
786    }
787
788    /// Get the length of the encoded format.
789    pub fn encoded_len(&self) -> usize {
790        self.user_key.encoded_len() + EPOCH_LEN
791    }
792}
793
794impl<'a> FullKey<&'a [u8]> {
795    /// Construct a [`FullKey`] from a byte slice.
796    pub fn decode(slice: &'a [u8]) -> Self {
797        let epoch_pos = slice.len() - EPOCH_LEN;
798        let epoch = (&slice[epoch_pos..]).get_u64();
799
800        Self {
801            user_key: UserKey::decode(&slice[..epoch_pos]),
802            epoch_with_gap: EpochWithGap::from_u64(epoch),
803        }
804    }
805
806    /// Construct a [`FullKey`] from a byte slice without `table_id` encoded.
807    pub fn from_slice_without_table_id(
808        table_id: TableId,
809        slice_without_table_id: &'a [u8],
810    ) -> Self {
811        let epoch_pos = slice_without_table_id.len() - EPOCH_LEN;
812        let epoch = (&slice_without_table_id[epoch_pos..]).get_u64();
813
814        Self {
815            user_key: UserKey::new(table_id, TableKey(&slice_without_table_id[..epoch_pos])),
816            epoch_with_gap: EpochWithGap::from_u64(epoch),
817        }
818    }
819
820    /// Construct a [`FullKey`] from a byte slice.
821    pub fn decode_reverse_epoch(slice: &'a [u8]) -> Self {
822        let epoch_pos = slice.len() - EPOCH_LEN;
823        let epoch = (&slice[epoch_pos..]).get_u64();
824
825        Self {
826            user_key: UserKey::decode(&slice[..epoch_pos]),
827            epoch_with_gap: EpochWithGap::from_u64(u64::MAX - epoch),
828        }
829    }
830
831    pub fn to_vec(self) -> FullKey<Vec<u8>> {
832        self.copy_into()
833    }
834
835    pub fn copy_into<T: CopyFromSlice + AsRef<[u8]>>(self) -> FullKey<T> {
836        FullKey {
837            user_key: self.user_key.copy_into(),
838            epoch_with_gap: self.epoch_with_gap,
839        }
840    }
841}
842
843impl FullKey<Vec<u8>> {
844    /// Calling this method may accidentally cause memory allocation when converting `Vec` into
845    /// `Bytes`
846    pub fn into_bytes(self) -> FullKey<Bytes> {
847        FullKey {
848            epoch_with_gap: self.epoch_with_gap,
849            user_key: self.user_key.into_bytes(),
850        }
851    }
852}
853
854impl<T: AsRef<[u8]>> FullKey<T> {
855    pub fn to_ref(&self) -> FullKey<&[u8]> {
856        FullKey {
857            user_key: self.user_key.as_ref(),
858            epoch_with_gap: self.epoch_with_gap,
859        }
860    }
861}
862
863impl<T: AsRef<[u8]>> FullKey<T> {
864    /// Use this method to override an old `FullKey<Vec<u8>>` with a `FullKey<&[u8]>` to own the
865    /// table key without reallocating a new `FullKey` object.
866    pub fn set<F>(&mut self, other: FullKey<F>)
867    where
868        T: SetSlice<F>,
869        F: AsRef<[u8]>,
870    {
871        self.user_key.set(other.user_key);
872        self.epoch_with_gap = other.epoch_with_gap;
873    }
874}
875
876impl<T: AsRef<[u8]> + Ord + Eq> Ord for FullKey<T> {
877    fn cmp(&self, other: &Self) -> std::cmp::Ordering {
878        // When `user_key` is the same, greater epoch comes first.
879        self.user_key
880            .cmp(&other.user_key)
881            .then_with(|| other.epoch_with_gap.cmp(&self.epoch_with_gap))
882    }
883}
884
885impl<T: AsRef<[u8]> + Ord + Eq> PartialOrd for FullKey<T> {
886    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
887        Some(self.cmp(other))
888    }
889}
890
891pub mod range_delete_backward_compatibility_serde_struct {
892    use bytes::{Buf, BufMut};
893    use risingwave_common::catalog::TableId;
894    use serde::{Deserialize, Serialize};
895
896    #[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
897    pub struct TableKey(Vec<u8>);
898
899    #[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
900    #[serde(from = "UserKeySerde", into = "UserKeySerde")]
901    pub struct UserKey {
902        // When comparing `UserKey`, we first compare `table_id`, then `table_key`. So the order of
903        // declaration matters.
904        pub table_id: TableId,
905        pub table_key: TableKey,
906    }
907
908    #[derive(Deserialize, Serialize)]
909    pub struct TableIdSerde {
910        table_id: u32,
911    }
912
913    #[derive(Deserialize, Serialize)]
914    struct UserKeySerde {
915        table_id: TableIdSerde,
916        table_key: TableKey,
917    }
918
919    impl From<UserKeySerde> for UserKey {
920        fn from(value: UserKeySerde) -> Self {
921            Self {
922                table_id: TableId::new(value.table_id.table_id),
923                table_key: value.table_key,
924            }
925        }
926    }
927
928    impl From<UserKey> for UserKeySerde {
929        fn from(value: UserKey) -> Self {
930            Self {
931                table_id: TableIdSerde {
932                    table_id: value.table_id.as_raw_id(),
933                },
934                table_key: value.table_key,
935            }
936        }
937    }
938
939    impl UserKey {
940        pub fn decode_length_prefixed(buf: &mut &[u8]) -> Self {
941            let table_id = buf.get_u32();
942            let len = buf.get_u32() as usize;
943            let data = buf[..len].to_vec();
944            buf.advance(len);
945            UserKey {
946                table_id: TableId::new(table_id),
947                table_key: TableKey(data),
948            }
949        }
950
951        pub fn encode_length_prefixed(&self, mut buf: impl BufMut) {
952            buf.put_u32(self.table_id.as_raw_id());
953            buf.put_u32(self.table_key.0.as_slice().len() as u32);
954            buf.put_slice(self.table_key.0.as_slice());
955        }
956    }
957
958    #[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
959    pub struct PointRange {
960        // When comparing `PointRange`, we first compare `left_user_key`, then
961        // `is_exclude_left_key`. Therefore the order of declaration matters.
962        pub left_user_key: UserKey,
963        /// `PointRange` represents the left user key itself if `is_exclude_left_key==false`
964        /// while represents the right δ Neighborhood of the left user key if
965        /// `is_exclude_left_key==true`.
966        pub is_exclude_left_key: bool,
967    }
968}
969
970pub trait EmptySliceRef {
971    fn empty_slice_ref<'a>() -> &'a Self;
972}
973
974static EMPTY_BYTES: Bytes = Bytes::new();
975impl EmptySliceRef for Bytes {
976    fn empty_slice_ref<'a>() -> &'a Self {
977        &EMPTY_BYTES
978    }
979}
980
981static EMPTY_VEC: Vec<u8> = Vec::new();
982impl EmptySliceRef for Vec<u8> {
983    fn empty_slice_ref<'a>() -> &'a Self {
984        &EMPTY_VEC
985    }
986}
987
988const EMPTY_SLICE: &[u8] = b"";
989impl EmptySliceRef for &[u8] {
990    fn empty_slice_ref<'b>() -> &'b Self {
991        &EMPTY_SLICE
992    }
993}
994
995/// Bound table key range with table id to generate a new user key range.
996pub fn bound_table_key_range<T: AsRef<[u8]> + EmptySliceRef>(
997    table_id: TableId,
998    table_key_range: &impl RangeBounds<TableKey<T>>,
999) -> (Bound<UserKey<&T>>, Bound<UserKey<&T>>) {
1000    let start = match table_key_range.start_bound() {
1001        Included(b) => Included(UserKey::new(table_id, TableKey(&b.0))),
1002        Excluded(b) => Excluded(UserKey::new(table_id, TableKey(&b.0))),
1003        Unbounded => Included(UserKey::new(table_id, TableKey(T::empty_slice_ref()))),
1004    };
1005
1006    let end = match table_key_range.end_bound() {
1007        Included(b) => Included(UserKey::new(table_id, TableKey(&b.0))),
1008        Excluded(b) => Excluded(UserKey::new(table_id, TableKey(&b.0))),
1009        Unbounded => {
1010            if let Some(next_table_id) = table_id.as_raw_id().checked_add(1) {
1011                Excluded(UserKey::new(
1012                    next_table_id.into(),
1013                    TableKey(T::empty_slice_ref()),
1014                ))
1015            } else {
1016                Unbounded
1017            }
1018        }
1019    };
1020
1021    (start, end)
1022}
1023
1024/// TODO: Temporary bypass full key check. Remove this field after #15099 is resolved.
1025pub struct FullKeyTracker<T: AsRef<[u8]> + Ord + Eq, const SKIP_DEDUP: bool = false> {
1026    pub latest_full_key: FullKey<T>,
1027    last_observed_epoch_with_gap: EpochWithGap,
1028}
1029
1030impl<T: AsRef<[u8]> + Ord + Eq, const SKIP_DEDUP: bool> FullKeyTracker<T, SKIP_DEDUP> {
1031    pub fn new(init_full_key: FullKey<T>) -> Self {
1032        let epoch_with_gap = init_full_key.epoch_with_gap;
1033        Self {
1034            latest_full_key: init_full_key,
1035            last_observed_epoch_with_gap: epoch_with_gap,
1036        }
1037    }
1038
1039    /// Check and observe a new full key during iteration
1040    ///
1041    /// # Examples:
1042    /// ```
1043    /// use bytes::Bytes;
1044    /// use risingwave_common::catalog::TableId;
1045    /// use risingwave_common::util::epoch::EPOCH_AVAILABLE_BITS;
1046    /// use risingwave_hummock_sdk::EpochWithGap;
1047    /// use risingwave_hummock_sdk::key::{FullKey, FullKeyTracker, TableKey};
1048    ///
1049    /// let table_id = TableId::new(1);
1050    /// let full_key1 = FullKey::new(table_id, TableKey(Bytes::from("c")), 5 << EPOCH_AVAILABLE_BITS);
1051    /// let mut a: FullKeyTracker<_> = FullKeyTracker::<Bytes>::new(full_key1.clone());
1052    ///
1053    /// // Panic on non-decreasing epoch observed for the same user key.
1054    /// // let full_key_with_larger_epoch = FullKey::new(table_id, TableKey(Bytes::from("c")), 6 << EPOCH_AVAILABLE_BITS);
1055    /// // a.observe(full_key_with_larger_epoch);
1056    ///
1057    /// // Panic on non-increasing user key observed.
1058    /// // let full_key_with_smaller_user_key = FullKey::new(table_id, TableKey(Bytes::from("b")), 3 << EPOCH_AVAILABLE_BITS);
1059    /// // a.observe(full_key_with_smaller_user_key);
1060    ///
1061    /// let full_key2 = FullKey::new(table_id, TableKey(Bytes::from("c")), 3 << EPOCH_AVAILABLE_BITS);
1062    /// assert_eq!(a.observe(full_key2.clone()), false);
1063    /// assert_eq!(a.latest_user_key(), &full_key2.user_key);
1064    ///
1065    /// let full_key3 = FullKey::new(table_id, TableKey(Bytes::from("f")), 4 << EPOCH_AVAILABLE_BITS);
1066    /// assert_eq!(a.observe(full_key3.clone()), true);
1067    /// assert_eq!(a.latest_user_key(), &full_key3.user_key);
1068    /// ```
1069    ///
1070    /// Return:
1071    /// - If the provided `key` contains a new user key, return true.
1072    /// - Otherwise: return false
1073    pub fn observe<F>(&mut self, key: FullKey<F>) -> bool
1074    where
1075        T: SetSlice<F>,
1076        F: AsRef<[u8]>,
1077    {
1078        self.observe_multi_version(key.user_key, once(key.epoch_with_gap))
1079    }
1080
1081    /// `epochs` comes from greater to smaller
1082    pub fn observe_multi_version<F>(
1083        &mut self,
1084        user_key: UserKey<F>,
1085        mut epochs: impl Iterator<Item = EpochWithGap>,
1086    ) -> bool
1087    where
1088        T: SetSlice<F>,
1089        F: AsRef<[u8]>,
1090    {
1091        let max_epoch_with_gap = epochs.next().expect("non-empty");
1092        let min_epoch_with_gap = epochs.fold(
1093            max_epoch_with_gap,
1094            |prev_epoch_with_gap, curr_epoch_with_gap| {
1095                assert!(
1096                    prev_epoch_with_gap > curr_epoch_with_gap,
1097                    "epoch list not sorted. prev: {:?}, curr: {:?}, user_key: {:?}",
1098                    prev_epoch_with_gap,
1099                    curr_epoch_with_gap,
1100                    user_key
1101                );
1102                curr_epoch_with_gap
1103            },
1104        );
1105        match self
1106            .latest_full_key
1107            .user_key
1108            .as_ref()
1109            .cmp(&user_key.as_ref())
1110        {
1111            Ordering::Less => {
1112                // Observe a new user key
1113
1114                // Reset epochs
1115                self.last_observed_epoch_with_gap = min_epoch_with_gap;
1116
1117                // Take the previous key and set latest key
1118                self.latest_full_key.set(FullKey {
1119                    user_key,
1120                    epoch_with_gap: min_epoch_with_gap,
1121                });
1122                true
1123            }
1124            Ordering::Equal => {
1125                if max_epoch_with_gap > self.last_observed_epoch_with_gap
1126                    || (!SKIP_DEDUP && max_epoch_with_gap == self.last_observed_epoch_with_gap)
1127                {
1128                    // Epoch from the same user key should be monotonically decreasing
1129                    panic!(
1130                        "key {:?} epoch {:?} >= prev epoch {:?}",
1131                        user_key, max_epoch_with_gap, self.last_observed_epoch_with_gap
1132                    );
1133                }
1134                self.last_observed_epoch_with_gap = min_epoch_with_gap;
1135                false
1136            }
1137            Ordering::Greater => {
1138                // User key should be monotonically increasing
1139                panic!(
1140                    "key {:?} <= prev key {:?}",
1141                    user_key,
1142                    FullKey {
1143                        user_key: self.latest_full_key.user_key.as_ref(),
1144                        epoch_with_gap: self.last_observed_epoch_with_gap
1145                    }
1146                );
1147            }
1148        }
1149    }
1150
1151    pub fn latest_user_key(&self) -> &UserKey<T> {
1152        &self.latest_full_key.user_key
1153    }
1154}
1155
1156#[cfg(test)]
1157mod tests {
1158    use risingwave_common::util::epoch::test_epoch;
1159
1160    use super::*;
1161
1162    #[test]
1163    fn test_encode_decode() {
1164        let epoch = test_epoch(1);
1165        let table_key = b"abc".to_vec();
1166        let key = FullKey::for_test(TableId::new(0), &table_key[..], 0);
1167        let buf = key.encode();
1168        assert_eq!(FullKey::decode(&buf), key);
1169        let key = FullKey::for_test(TableId::new(1), &table_key[..], epoch);
1170        let buf = key.encode();
1171        assert_eq!(FullKey::decode(&buf), key);
1172        let mut table_key = vec![1];
1173        let a = FullKey::for_test(TableId::new(1), table_key.clone(), epoch);
1174        table_key[0] = 2;
1175        let b = FullKey::for_test(TableId::new(1), table_key.clone(), epoch);
1176        table_key[0] = 129;
1177        let c = FullKey::for_test(TableId::new(1), table_key, epoch);
1178        assert!(a.lt(&b));
1179        assert!(b.lt(&c));
1180    }
1181
1182    #[test]
1183    fn test_key_cmp() {
1184        let epoch = test_epoch(1);
1185        let epoch2 = test_epoch(2);
1186        // 1 compared with 256 under little-endian encoding would return wrong result.
1187        let key1 = FullKey::for_test(TableId::new(0), b"0".to_vec(), epoch);
1188        let key2 = FullKey::for_test(TableId::new(1), b"0".to_vec(), epoch);
1189        let key3 = FullKey::for_test(TableId::new(1), b"1".to_vec(), epoch2);
1190        let key4 = FullKey::for_test(TableId::new(1), b"1".to_vec(), epoch);
1191
1192        assert_eq!(key1.cmp(&key1), Ordering::Equal);
1193        assert_eq!(key1.cmp(&key2), Ordering::Less);
1194        assert_eq!(key2.cmp(&key3), Ordering::Less);
1195        assert_eq!(key3.cmp(&key4), Ordering::Less);
1196    }
1197
1198    #[test]
1199    fn test_prev_key() {
1200        assert_eq!(prev_key(b"123"), b"122");
1201        assert_eq!(prev_key(b"12\x00"), b"11\xff");
1202        assert_eq!(prev_key(b"\x00\x00"), b"\xff\xff");
1203        assert_eq!(prev_key(b"\x00\x01"), b"\x00\x00");
1204        assert_eq!(prev_key(b"T"), b"S");
1205        assert_eq!(prev_key(b""), b"");
1206    }
1207
1208    #[test]
1209    fn test_bound_table_key_range() {
1210        assert_eq!(
1211            bound_table_key_range(
1212                TableId::default(),
1213                &(
1214                    Included(TableKey(b"a".to_vec())),
1215                    Included(TableKey(b"b".to_vec()))
1216                )
1217            ),
1218            (
1219                Included(UserKey::for_test(TableId::default(), &b"a".to_vec())),
1220                Included(UserKey::for_test(TableId::default(), &b"b".to_vec()),)
1221            )
1222        );
1223        assert_eq!(
1224            bound_table_key_range(
1225                TableId::from(1),
1226                &(Included(TableKey(b"a".to_vec())), Unbounded)
1227            ),
1228            (
1229                Included(UserKey::for_test(TableId::from(1), &b"a".to_vec())),
1230                Excluded(UserKey::for_test(TableId::from(2), &b"".to_vec()),)
1231            )
1232        );
1233        assert_eq!(
1234            bound_table_key_range(
1235                TableId::from(u32::MAX),
1236                &(Included(TableKey(b"a".to_vec())), Unbounded)
1237            ),
1238            (
1239                Included(UserKey::for_test(TableId::from(u32::MAX), &b"a".to_vec())),
1240                Unbounded,
1241            )
1242        );
1243    }
1244
1245    #[test]
1246    fn test_next_full_key() {
1247        let user_key = b"aaa".to_vec();
1248        let epoch: HummockEpoch = 3;
1249        let mut full_key = key_with_epoch(user_key, epoch);
1250        full_key = next_full_key(full_key.as_slice());
1251        assert_eq!(full_key, key_with_epoch(b"aaa".to_vec(), 2));
1252        full_key = next_full_key(full_key.as_slice());
1253        assert_eq!(full_key, key_with_epoch(b"aaa".to_vec(), 1));
1254        full_key = next_full_key(full_key.as_slice());
1255        assert_eq!(full_key, key_with_epoch(b"aaa".to_vec(), 0));
1256        full_key = next_full_key(full_key.as_slice());
1257        assert_eq!(
1258            full_key,
1259            key_with_epoch("aab".as_bytes().to_vec(), HummockEpoch::MAX)
1260        );
1261        assert_eq!(
1262            next_full_key(&key_with_epoch(b"\xff".to_vec(), 0)),
1263            Vec::<u8>::new()
1264        );
1265    }
1266
1267    #[test]
1268    fn test_prev_full_key() {
1269        let user_key = b"aab";
1270        let epoch: HummockEpoch = HummockEpoch::MAX - 3;
1271        let mut full_key = key_with_epoch(user_key.to_vec(), epoch);
1272        full_key = prev_full_key(full_key.as_slice());
1273        assert_eq!(
1274            full_key,
1275            key_with_epoch(b"aab".to_vec(), HummockEpoch::MAX - 2)
1276        );
1277        full_key = prev_full_key(full_key.as_slice());
1278        assert_eq!(
1279            full_key,
1280            key_with_epoch(b"aab".to_vec(), HummockEpoch::MAX - 1)
1281        );
1282        full_key = prev_full_key(full_key.as_slice());
1283        assert_eq!(full_key, key_with_epoch(b"aab".to_vec(), HummockEpoch::MAX));
1284        full_key = prev_full_key(full_key.as_slice());
1285        assert_eq!(full_key, key_with_epoch(b"aaa".to_vec(), 0));
1286
1287        assert_eq!(
1288            prev_full_key(&key_with_epoch(b"\x00".to_vec(), HummockEpoch::MAX)),
1289            Vec::<u8>::new()
1290        );
1291    }
1292
1293    #[test]
1294    fn test_user_key_order() {
1295        let a = UserKey::new(TableId::new(1), TableKey(b"aaa".to_vec()));
1296        let b = UserKey::new(TableId::new(2), TableKey(b"aaa".to_vec()));
1297        let c = UserKey::new(TableId::new(2), TableKey(b"bbb".to_vec()));
1298        assert!(a.lt(&b));
1299        assert!(b.lt(&c));
1300        let a = a.encode();
1301        let b = b.encode();
1302        let c = c.encode();
1303        assert!(a.lt(&b));
1304        assert!(b.lt(&c));
1305    }
1306
1307    #[test]
1308    fn test_prefixed_range_with_vnode() {
1309        let concat = |vnode: usize, b: &[u8]| -> Bytes {
1310            prefix_slice_with_vnode(VirtualNode::from_index(vnode), b)
1311        };
1312        assert_eq!(
1313            prefixed_range_with_vnode(
1314                (Included(Bytes::from("1")), Included(Bytes::from("2"))),
1315                VirtualNode::from_index(233),
1316            ),
1317            (
1318                Included(TableKey(concat(233, b"1"))),
1319                Included(TableKey(concat(233, b"2")))
1320            )
1321        );
1322        assert_eq!(
1323            prefixed_range_with_vnode(
1324                (Excluded(Bytes::from("1")), Excluded(Bytes::from("2"))),
1325                VirtualNode::from_index(233),
1326            ),
1327            (
1328                Excluded(TableKey(concat(233, b"1"))),
1329                Excluded(TableKey(concat(233, b"2")))
1330            )
1331        );
1332        assert_eq!(
1333            prefixed_range_with_vnode(
1334                (Bound::<Bytes>::Unbounded, Bound::<Bytes>::Unbounded),
1335                VirtualNode::from_index(233),
1336            ),
1337            (
1338                Included(TableKey(concat(233, b""))),
1339                Excluded(TableKey(concat(234, b"")))
1340            )
1341        );
1342        let max_vnode = VirtualNode::MAX_REPRESENTABLE.to_index();
1343        assert_eq!(
1344            prefixed_range_with_vnode(
1345                (Bound::<Bytes>::Unbounded, Bound::<Bytes>::Unbounded),
1346                VirtualNode::from_index(max_vnode),
1347            ),
1348            (Included(TableKey(concat(max_vnode, b""))), Unbounded)
1349        );
1350        let second_max_vnode = max_vnode - 1;
1351        assert_eq!(
1352            prefixed_range_with_vnode(
1353                (Bound::<Bytes>::Unbounded, Bound::<Bytes>::Unbounded),
1354                VirtualNode::from_index(second_max_vnode),
1355            ),
1356            (
1357                Included(TableKey(concat(second_max_vnode, b""))),
1358                Excluded(TableKey(concat(max_vnode, b"")))
1359            )
1360        );
1361    }
1362
1363    #[test]
1364    fn test_single_vnode_range() {
1365        let left_bound = vec![
1366            Included(b"0".as_slice()),
1367            Excluded(b"0".as_slice()),
1368            Unbounded,
1369        ];
1370        let right_bound = vec![
1371            Included(b"1".as_slice()),
1372            Excluded(b"1".as_slice()),
1373            Unbounded,
1374        ];
1375        for vnode in 0..VirtualNode::MAX_COUNT {
1376            for left in &left_bound {
1377                for right in &right_bound {
1378                    assert_eq!(
1379                        (vnode, vnode + 1),
1380                        vnode_range(&prefixed_range_with_vnode::<&[u8]>(
1381                            (*left, *right),
1382                            VirtualNode::from_index(vnode)
1383                        ))
1384                    )
1385                }
1386            }
1387        }
1388    }
1389}
risingwave_hummock_sdk/key.rs

risingwave_hummock_sdk/
key.rs
