MeiliSearch/milli/src/external_documents_ids.rs
2023-11-23 14:11:38 +01:00

76 lines
2.4 KiB
Rust

use std::collections::HashMap;
use heed::types::Str;
use heed::{Database, RoIter, RoTxn, RwTxn};
use crate::{DocumentId, BEU32};
pub enum DocumentOperationKind {
Create,
Delete,
}
pub struct DocumentOperation {
pub external_id: String,
pub internal_id: DocumentId,
pub kind: DocumentOperationKind,
}
pub struct ExternalDocumentsIds(Database<Str, BEU32>);
impl ExternalDocumentsIds {
pub fn new(db: Database<Str, BEU32>) -> ExternalDocumentsIds {
ExternalDocumentsIds(db)
}
/// Returns `true` if hard and soft external documents lists are empty.
pub fn is_empty(&self, rtxn: &RoTxn) -> heed::Result<bool> {
self.0.is_empty(rtxn).map_err(Into::into)
}
pub fn get<A: AsRef<str>>(&self, rtxn: &RoTxn, external_id: A) -> heed::Result<Option<u32>> {
self.0.get(rtxn, external_id.as_ref())
}
/// An helper function to debug this type, returns an `HashMap` of both,
/// soft and hard fst maps, combined.
pub fn to_hash_map(&self, rtxn: &RoTxn) -> heed::Result<HashMap<String, u32>> {
let mut map = HashMap::default();
for result in self.0.iter(rtxn)? {
let (external, internal) = result?;
map.insert(external.to_owned(), internal);
}
Ok(map)
}
/// Applies the list of operations passed as argument, modifying the current external to internal id mapping.
///
/// If the list contains multiple operations on the same external id, then the result is unspecified.
///
/// # Panics
///
/// - If attempting to delete a document that doesn't exist
/// - If attempting to create a document that already exists
pub fn apply(&self, wtxn: &mut RwTxn, operations: Vec<DocumentOperation>) -> heed::Result<()> {
for DocumentOperation { external_id, internal_id, kind } in operations {
match kind {
DocumentOperationKind::Create => {
self.0.put(wtxn, &external_id, &internal_id)?;
}
DocumentOperationKind::Delete => {
if !self.0.delete(wtxn, &external_id)? {
panic!("Attempting to delete a non-existing document")
}
}
}
}
Ok(())
}
/// Returns an iterator over all the external ids.
pub fn iter<'t>(&self, rtxn: &'t RoTxn) -> heed::Result<RoIter<'t, Str, BEU32>> {
self.0.iter(rtxn)
}
}