continuwuity/src/service/rooms/search/data.rs
Jason Volk 7ad7badd60 devirtualize service Data traits
Signed-off-by: Jason Volk <jason@zemos.net>
2024-06-30 18:01:20 +00:00

95 lines
2.7 KiB
Rust

use std::sync::Arc;
use database::KvTree;
use ruma::RoomId;
use crate::{services, utils, KeyValueDatabase, Result};
type SearchPdusResult<'a> = Result<Option<(Box<dyn Iterator<Item = Vec<u8>> + 'a>, Vec<String>)>>;
pub struct Data {
tokenids: Arc<dyn KvTree>,
}
impl Data {
pub(super) fn new(db: &Arc<KeyValueDatabase>) -> Self {
Self {
tokenids: db.tokenids.clone(),
}
}
pub(super) fn index_pdu(&self, shortroomid: u64, pdu_id: &[u8], message_body: &str) -> Result<()> {
let mut batch = tokenize(message_body).map(|word| {
let mut key = shortroomid.to_be_bytes().to_vec();
key.extend_from_slice(word.as_bytes());
key.push(0xFF);
key.extend_from_slice(pdu_id); // TODO: currently we save the room id a second time here
(key, Vec::new())
});
self.tokenids.insert_batch(&mut batch)
}
pub(super) fn deindex_pdu(&self, shortroomid: u64, pdu_id: &[u8], message_body: &str) -> Result<()> {
let batch = tokenize(message_body).map(|word| {
let mut key = shortroomid.to_be_bytes().to_vec();
key.extend_from_slice(word.as_bytes());
key.push(0xFF);
key.extend_from_slice(pdu_id); // TODO: currently we save the room id a second time here
key
});
for token in batch {
self.tokenids.remove(&token)?;
}
Ok(())
}
pub(super) fn search_pdus<'a>(&'a self, room_id: &RoomId, search_string: &str) -> SearchPdusResult<'a> {
let prefix = services()
.rooms
.short
.get_shortroomid(room_id)?
.expect("room exists")
.to_be_bytes()
.to_vec();
let words: Vec<_> = tokenize(search_string).collect();
let iterators = words.clone().into_iter().map(move |word| {
let mut prefix2 = prefix.clone();
prefix2.extend_from_slice(word.as_bytes());
prefix2.push(0xFF);
let prefix3 = prefix2.clone();
let mut last_possible_id = prefix2.clone();
last_possible_id.extend_from_slice(&u64::MAX.to_be_bytes());
self.tokenids
.iter_from(&last_possible_id, true) // Newest pdus first
.take_while(move |(k, _)| k.starts_with(&prefix2))
.map(move |(key, _)| key[prefix3.len()..].to_vec())
});
let Some(common_elements) = utils::common_elements(iterators, |a, b| {
// We compare b with a because we reversed the iterator earlier
b.cmp(a)
}) else {
return Ok(None);
};
Ok(Some((Box::new(common_elements), words)))
}
}
/// Splits a string into tokens used as keys in the search inverted index
///
/// This may be used to tokenize both message bodies (for indexing) or search
/// queries (for querying).
fn tokenize(body: &str) -> impl Iterator<Item = String> + '_ {
body.split_terminator(|c: char| !c.is_alphanumeric())
.filter(|s| !s.is_empty())
.filter(|word| word.len() <= 50)
.map(str::to_lowercase)
}