Files
Stalwart/crates/store/src/query/sort.rs

403 lines
15 KiB
Rust

/*
* Copyright (c) 2023 Stalwart Labs Ltd.
*
* This file is part of the Stalwart Mail Server.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as
* published by the Free Software Foundation, either version 3 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
* in the LICENSE file at the top-level directory of this distribution.
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* You can be released from the requirements of the AGPLv3 license by
* purchasing a commercial license. Please contact licensing@stalw.art
* for more details.
*/
use std::cmp::Ordering;
use ahash::{AHashMap, AHashSet};
use crate::{
write::{key::DeserializeBigEndian, ValueClass},
IndexKeyPrefix, IterateParams, Store, ValueKey, U32_LEN,
};
use super::{Comparator, ResultSet, SortedResultSet};
pub struct Pagination {
requested_position: i32,
position: i32,
pub limit: usize,
anchor: u32,
anchor_offset: i32,
has_anchor: bool,
anchor_found: bool,
pub ids: Vec<u64>,
prefix_key: Option<ValueKey<ValueClass>>,
prefix_unique: bool,
}
impl Store {
pub async fn sort(
&self,
result_set: ResultSet,
mut comparators: Vec<Comparator>,
mut paginate: Pagination,
) -> crate::Result<SortedResultSet> {
paginate.limit = match (result_set.results.len(), paginate.limit) {
(0, _) => {
return Ok(SortedResultSet {
position: paginate.position,
ids: vec![],
found_anchor: true,
});
}
(_, 0) => result_set.results.len() as usize,
(a, b) => std::cmp::min(a as usize, b),
};
if comparators.len() == 1 && !paginate.prefix_unique {
match comparators.pop().unwrap() {
Comparator::Field { field, ascending } => {
let mut results = result_set.results;
self.iterate(
IterateParams::new(
IndexKeyPrefix {
account_id: result_set.account_id,
collection: result_set.collection,
field,
},
IndexKeyPrefix {
account_id: result_set.account_id,
collection: result_set.collection,
field: field + 1,
},
)
.no_values()
.set_ascending(ascending),
|key, _| {
let document_id = key.deserialize_be_u32(key.len() - U32_LEN)?;
Ok(!results.remove(document_id) || paginate.add(0, document_id))
},
)
.await?;
// Add remaining items not present in the index
if !results.is_empty() && !paginate.is_full() {
for document_id in results {
if !paginate.add(0, document_id) {
break;
}
}
}
}
Comparator::DocumentSet { set, ascending } => {
let in_set = &result_set.results & &set;
let not_in_set = &result_set.results ^ &in_set;
let sets = if ascending {
[in_set, not_in_set]
} else {
[not_in_set, in_set]
};
'outer: for set in sets {
for document_id in set {
if !paginate.add(0, document_id) {
break 'outer;
}
}
}
}
}
// Obtain prefixes
let prefix_key = paginate.prefix_key.take();
let mut sorted_results = paginate.build();
if let Some(prefix_key) = prefix_key {
for id in sorted_results.ids.iter_mut() {
if let Some(prefix_id) = self
.get_value::<u32>(prefix_key.clone().with_document_id(*id as u32))
.await?
{
*id |= (prefix_id as u64) << 32;
}
}
}
Ok(sorted_results)
} else if comparators.len() > 1 {
//TODO improve this algorithm, avoid re-sorting in memory.
let mut sorted_ids = AHashMap::with_capacity(paginate.limit);
for (pos, comparator) in comparators.into_iter().take(4).enumerate() {
match comparator {
Comparator::Field { field, ascending } => {
let mut results = result_set.results.clone();
let mut prev_data = vec![];
let mut has_grouped_ids = false;
let mut idx = 0;
self.iterate(
IterateParams::new(
IndexKeyPrefix {
account_id: result_set.account_id,
collection: result_set.collection,
field,
},
IndexKeyPrefix {
account_id: result_set.account_id,
collection: result_set.collection,
field: field + 1,
},
)
.no_values()
.set_ascending(ascending),
|key, _| {
let id_pos = key.len() - U32_LEN;
let document_id = key.deserialize_be_u32(id_pos)?;
Ok(if results.remove(document_id) {
let data = key.get(IndexKeyPrefix::len()..id_pos).ok_or_else(
|| {
crate::Error::InternalError(
"Invalid key found in index".to_string(),
)
},
)?;
debug_assert!(!data.is_empty());
if data != prev_data {
idx += 1;
prev_data = data.to_vec();
} else {
has_grouped_ids = true;
}
sorted_ids.entry(document_id).or_insert([0u32; 4])[pos] = idx;
!results.is_empty()
} else {
true
})
},
)
.await?;
// Add remaining items not present in the index
if !results.is_empty() {
idx += 1;
for document_id in results {
sorted_ids.entry(document_id).or_insert([0u32; 4])[pos] = idx;
}
} else if !has_grouped_ids {
// If we are sorting by multiple fields and we don't have grouped ids, we can
// stop here
break;
}
}
Comparator::DocumentSet { set, ascending } => {
let in_set = &result_set.results & &set;
let not_in_set = &result_set.results ^ &in_set;
let sets = if ascending {
[(in_set, 0), (not_in_set, 1)]
} else {
[(not_in_set, 0), (in_set, 1)]
};
for (document_ids, idx) in sets {
for document_id in document_ids {
sorted_ids.entry(document_id).or_insert([0u32; 4])[pos] = idx;
}
}
}
}
}
let mut seen_prefixes = AHashSet::new();
let mut sorted_ids = sorted_ids.into_iter().collect::<Vec<_>>();
sorted_ids.sort_by(|a, b| match a.1.cmp(&b.1) {
Ordering::Equal => a.0.cmp(&b.0),
other => other,
});
for (document_id, _) in sorted_ids {
// Obtain document prefixId
let prefix_id = if let Some(prefix_key) = &paginate.prefix_key {
if let Some(prefix_id) = self
.get_value(prefix_key.clone().with_document_id(document_id))
.await?
{
if paginate.prefix_unique && !seen_prefixes.insert(prefix_id) {
continue;
}
prefix_id
} else {
// Document no longer exists?
continue;
}
} else {
0
};
// Add document to results
if !paginate.add(prefix_id, document_id) {
break;
}
}
Ok(paginate.build())
} else {
let mut seen_prefixes = AHashSet::new();
for document_id in result_set.results {
// Obtain document prefixId
let prefix_id = if let Some(prefix_key) = &paginate.prefix_key {
if let Some(prefix_id) = self
.get_value(prefix_key.clone().with_document_id(document_id))
.await?
{
if paginate.prefix_unique && !seen_prefixes.insert(prefix_id) {
continue;
}
prefix_id
} else {
// Document no longer exists?
continue;
}
} else {
0
};
// Add document to results
if !paginate.add(prefix_id, document_id) {
break;
}
}
Ok(paginate.build())
}
}
}
impl Pagination {
pub fn new(limit: usize, position: i32, anchor: Option<u32>, anchor_offset: i32) -> Self {
let (has_anchor, anchor) = anchor.map(|anchor| (true, anchor)).unwrap_or((false, 0));
Self {
requested_position: position,
position,
limit,
anchor,
anchor_offset,
has_anchor,
anchor_found: false,
ids: Vec::with_capacity(limit),
prefix_key: None,
prefix_unique: false,
}
}
pub fn with_prefix_key(mut self, prefix_key: ValueKey<ValueClass>) -> Self {
self.prefix_key = Some(prefix_key);
self
}
pub fn with_prefix_unique(mut self, prefix_unique: bool) -> Self {
self.prefix_unique = prefix_unique;
self
}
pub fn add(&mut self, prefix_id: u32, document_id: u32) -> bool {
let id = ((prefix_id as u64) << 32) | document_id as u64;
// Pagination
if !self.has_anchor {
if self.position >= 0 {
if self.position > 0 {
self.position -= 1;
} else {
self.ids.push(id);
if self.ids.len() == self.limit {
return false;
}
}
} else {
self.ids.push(id);
}
} else if self.anchor_offset >= 0 {
if !self.anchor_found {
if document_id != self.anchor {
return true;
}
self.anchor_found = true;
}
if self.anchor_offset > 0 {
self.anchor_offset -= 1;
} else {
self.ids.push(id);
if self.ids.len() == self.limit {
return false;
}
}
} else {
self.anchor_found = document_id == self.anchor;
self.ids.push(id);
if self.anchor_found {
self.position = self.anchor_offset;
return false;
}
}
true
}
pub fn is_full(&self) -> bool {
self.ids.len() == self.limit
}
pub fn build(self) -> SortedResultSet {
let mut result = SortedResultSet {
ids: self.ids,
position: 0,
found_anchor: !self.has_anchor || self.anchor_found,
};
if result.found_anchor {
if !self.has_anchor && self.requested_position >= 0 {
result.position = if self.position == 0 {
self.requested_position
} else {
0
};
} else if self.position >= 0 {
result.position = self.position;
} else {
let position = self.position.unsigned_abs() as usize;
let start_offset = if position < result.ids.len() {
result.ids.len() - position
} else {
0
};
result.position = start_offset as i32;
let end_offset = if self.limit > 0 {
std::cmp::min(start_offset + self.limit, result.ids.len())
} else {
result.ids.len()
};
result.ids = result.ids[start_offset..end_offset].to_vec()
}
}
result
}
}