MeiliSearch/milli/src/update/new/indexer/document_operation.rs
2024-09-10 17:37:52 +01:00

447 lines
18 KiB
Rust

use std::borrow::Cow;
use std::collections::{BTreeMap, HashMap};
use std::sync::Arc;
use heed::types::Bytes;
use heed::RoTxn;
use memmap2::Mmap;
use rayon::iter::{IntoParallelIterator, ParallelIterator};
use IndexDocumentsMethod as Idm;
use super::super::document_change::DocumentChange;
use super::super::items_pool::ItemsPool;
use super::DocumentChanges;
use crate::documents::PrimaryKey;
use crate::update::new::{Deletion, Insertion, KvReaderFieldId, KvWriterFieldId, Update};
use crate::update::{AvailableIds, IndexDocumentsMethod};
use crate::{DocumentId, Error, FieldsIdsMap, Index, Result, UserError};
pub struct DocumentOperation<'pl> {
operations: Vec<Payload<'pl>>,
index_documents_method: IndexDocumentsMethod,
}
pub enum Payload<'pl> {
Addition(&'pl [u8]),
Deletion(Vec<String>),
}
pub struct PayloadStats {
pub document_count: usize,
pub bytes: u64,
}
#[derive(Clone)]
enum InnerDocOp<'pl> {
Addition(DocumentOffset<'pl>),
Deletion,
}
/// Represents an offset where a document lives
/// in an mmapped grenad reader file.
#[derive(Clone)]
pub struct DocumentOffset<'pl> {
/// The mmapped payload files.
pub content: &'pl [u8],
}
impl<'pl> DocumentOperation<'pl> {
pub fn new(method: IndexDocumentsMethod) -> Self {
Self { operations: Default::default(), index_documents_method: method }
}
/// TODO please give me a type
/// The payload is expected to be in the grenad format
pub fn add_documents(&mut self, payload: &'pl Mmap) -> Result<PayloadStats> {
payload.advise(memmap2::Advice::Sequential)?;
let document_count = memchr::Memchr::new(b'\n', &payload[..]).count();
self.operations.push(Payload::Addition(&payload[..]));
Ok(PayloadStats { bytes: payload.len() as u64, document_count })
}
pub fn delete_documents(&mut self, to_delete: Vec<String>) {
self.operations.push(Payload::Deletion(to_delete))
}
}
impl<'p, 'pl: 'p> DocumentChanges<'p> for DocumentOperation<'pl> {
type Parameter = (&'p Index, &'p RoTxn<'p>, &'p PrimaryKey<'p>);
fn document_changes(
self,
fields_ids_map: &mut FieldsIdsMap,
param: Self::Parameter,
) -> Result<impl ParallelIterator<Item = Result<DocumentChange>> + Clone + 'p> {
let (index, rtxn, primary_key) = param;
let documents_ids = index.documents_ids(rtxn)?;
let mut available_docids = AvailableIds::new(&documents_ids);
let mut docids_version_offsets = HashMap::<CowStr<'pl>, _>::new();
for operation in self.operations {
match operation {
Payload::Addition(payload) => {
let mut iter =
serde_json::Deserializer::from_slice(payload).into_iter::<TopLevelMap>();
/// TODO manage the error
let mut previous_offset = 0;
while let Some(document) = iter.next().transpose().unwrap() {
// TODO Fetch all document fields to fill the fields ids map
document.0.keys().for_each(|key| {
fields_ids_map.insert(key.as_ref());
});
// TODO we must manage the TooManyDocumentIds,InvalidDocumentId
// we must manage the unwrap
let external_document_id =
match get_docid(&document, &[primary_key.name()]).unwrap() {
Some(document_id) => document_id,
None => {
return Err(UserError::MissingDocumentId {
primary_key: primary_key.name().to_string(),
document: todo!(),
// document: obkv_to_object(document, &batch_index)?,
}
.into());
}
};
// let external_document_id =
// match primary_key.document_id(document, &batch_index)? {
// Ok(document_id) => Ok(document_id),
// Err(DocumentIdExtractionError::InvalidDocumentId(user_error)) => {
// Err(user_error)
// }
// Err(DocumentIdExtractionError::MissingDocumentId) => {
// Err(UserError::MissingDocumentId {
// primary_key: primary_key.name().to_string(),
// document: obkv_to_object(document, &batch_index)?,
// })
// }
// Err(DocumentIdExtractionError::TooManyDocumentIds(_)) => {
// Err(UserError::TooManyDocumentIds {
// primary_key: primary_key.name().to_string(),
// document: obkv_to_object(document, &batch_index)?,
// })
// }
// }?;
let current_offset = iter.byte_offset();
let document_operation = InnerDocOp::Addition(DocumentOffset {
content: &payload[previous_offset..current_offset],
});
match docids_version_offsets.get_mut(external_document_id.as_ref()) {
None => {
let docid = match index
.external_documents_ids()
.get(rtxn, &external_document_id)?
{
Some(docid) => docid,
None => available_docids
.next()
.ok_or(Error::UserError(UserError::DocumentLimitReached))?,
};
docids_version_offsets.insert(
external_document_id,
(docid, vec![document_operation]),
);
}
// TODO clean the code to make sure we clean the useless operations
// add a method to the MergeChanges trait
Some((_, offsets)) => offsets.push(document_operation),
}
previous_offset = iter.byte_offset();
}
}
Payload::Deletion(to_delete) => {
for external_document_id in to_delete {
match docids_version_offsets.get_mut(external_document_id.as_str()) {
None => {
let docid = match index
.external_documents_ids()
.get(rtxn, &external_document_id)?
{
Some(docid) => docid,
None => available_docids
.next()
.ok_or(Error::UserError(UserError::DocumentLimitReached))?,
};
docids_version_offsets.insert(
CowStr(external_document_id.into()),
(docid, vec![InnerDocOp::Deletion]),
);
}
Some((_, offsets)) => offsets.push(InnerDocOp::Deletion),
}
}
}
}
}
/// TODO is it the best way to provide FieldsIdsMap to the parallel iterator?
let fields_ids_map = fields_ids_map.clone();
// TODO We must drain the HashMap into a Vec because rayon::hash_map::IntoIter: !Clone
let mut docids_version_offsets: Vec<_> = docids_version_offsets.drain().collect();
// Reorder the offsets to make sure we iterate on the file sequentially
match self.index_documents_method {
Idm::ReplaceDocuments => MergeDocumentForReplacement::sort(&mut docids_version_offsets),
Idm::UpdateDocuments => MergeDocumentForUpdates::sort(&mut docids_version_offsets),
}
Ok(docids_version_offsets
.into_par_iter()
.map_with(
Arc::new(ItemsPool::new(|| index.read_txn().map_err(crate::Error::from))),
move |context_pool, (external_docid, (internal_docid, operations))| {
context_pool.with(|rtxn| {
let document_merge_function = match self.index_documents_method {
Idm::ReplaceDocuments => MergeDocumentForReplacement::merge,
Idm::UpdateDocuments => MergeDocumentForUpdates::merge,
};
document_merge_function(
rtxn,
index,
&fields_ids_map,
internal_docid,
external_docid.to_string(), // TODO do not clone
&operations,
)
})
},
)
.filter_map(Result::transpose))
}
}
trait MergeChanges {
/// Reorders the offsets to make sure we iterate on the file sequentially.
fn sort(changes_offsets: &mut [(CowStr, (DocumentId, Vec<InnerDocOp>))]);
fn merge(
rtxn: &RoTxn,
index: &Index,
fields_ids_map: &FieldsIdsMap,
docid: DocumentId,
external_docid: String,
operations: &[InnerDocOp],
) -> Result<Option<DocumentChange>>;
}
struct MergeDocumentForReplacement;
impl MergeChanges for MergeDocumentForReplacement {
/// Reorders to read only the last change.
fn sort(changes_offsets: &mut [(CowStr, (DocumentId, Vec<InnerDocOp>))]) {
changes_offsets.sort_unstable_by_key(|(_, (_, offsets))| {
offsets
.iter()
.rev()
.find_map(|ido| match ido {
InnerDocOp::Addition(add) => Some(add.content.as_ptr() as usize),
InnerDocOp::Deletion => None,
})
.unwrap_or(0)
});
}
/// Returns only the most recent version of a document based on the updates from the payloads.
///
/// This function is only meant to be used when doing a replacement and not an update.
fn merge(
rtxn: &RoTxn,
index: &Index,
fields_ids_map: &FieldsIdsMap,
docid: DocumentId,
external_docid: String,
operations: &[InnerDocOp],
) -> Result<Option<DocumentChange>> {
let current = index.documents.remap_data_type::<Bytes>().get(rtxn, &docid)?;
let current: Option<&KvReaderFieldId> = current.map(Into::into);
match operations.last() {
Some(InnerDocOp::Addition(DocumentOffset { content })) => {
let map: TopLevelMap = serde_json::from_slice(content).unwrap();
let mut document_entries = Vec::new();
for (key, v) in map.0 {
let id = fields_ids_map.id(key.as_ref()).unwrap();
document_entries.push((id, v));
}
document_entries.sort_unstable_by_key(|(id, _)| *id);
let mut writer = KvWriterFieldId::memory();
document_entries
.into_iter()
.for_each(|(id, value)| writer.insert(id, value.get()).unwrap());
let new = writer.into_boxed();
match current {
Some(current) => {
let update = Update::create(docid, external_docid, current.boxed(), new);
Ok(Some(DocumentChange::Update(update)))
}
None => {
let insertion = Insertion::create(docid, external_docid, new);
Ok(Some(DocumentChange::Insertion(insertion)))
}
}
}
Some(InnerDocOp::Deletion) => match current {
Some(current) => {
let deletion = Deletion::create(docid, external_docid, current.boxed());
Ok(Some(DocumentChange::Deletion(deletion)))
}
None => Ok(None),
},
None => Ok(None), // but it's strange
}
}
}
struct MergeDocumentForUpdates;
impl MergeChanges for MergeDocumentForUpdates {
/// Reorders to read the first changes first so that it's faster to read the first one and then the rest.
fn sort(changes_offsets: &mut [(CowStr, (DocumentId, Vec<InnerDocOp>))]) {
changes_offsets.sort_unstable_by_key(|(_, (_, offsets))| {
offsets
.iter()
.find_map(|ido| match ido {
InnerDocOp::Addition(add) => Some(add.content.as_ptr() as usize),
InnerDocOp::Deletion => None,
})
.unwrap_or(0)
});
}
/// Reads the previous version of a document from the database, the new versions
/// in the grenad update files and merges them to generate a new boxed obkv.
///
/// This function is only meant to be used when doing an update and not a replacement.
fn merge(
rtxn: &RoTxn,
index: &Index,
fields_ids_map: &FieldsIdsMap,
docid: DocumentId,
external_docid: String,
operations: &[InnerDocOp],
) -> Result<Option<DocumentChange>> {
let mut document = BTreeMap::<_, Cow<_>>::new();
let current = index.documents.remap_data_type::<Bytes>().get(rtxn, &docid)?;
let current: Option<&KvReaderFieldId> = current.map(Into::into);
if operations.is_empty() {
return Ok(None); // but it's strange
}
let last_deletion = operations.iter().rposition(|op| matches!(op, InnerDocOp::Deletion));
let operations = &operations[last_deletion.map_or(0, |i| i + 1)..];
// If there was a deletion we must not start
// from the original document but from scratch.
if last_deletion.is_none() {
if let Some(current) = current {
current.into_iter().for_each(|(k, v)| {
document.insert(k, v.into());
});
}
}
if operations.is_empty() {
match current {
Some(current) => {
let deletion = Deletion::create(docid, external_docid, current.boxed());
return Ok(Some(DocumentChange::Deletion(deletion)));
}
None => return Ok(None),
}
}
for operation in operations {
let DocumentOffset { content } = match operation {
InnerDocOp::Addition(offset) => offset,
InnerDocOp::Deletion => {
unreachable!("Deletion in document operations")
}
};
let map: TopLevelMap = serde_json::from_slice(content).unwrap();
for (key, v) in map.0 {
let id = fields_ids_map.id(key.as_ref()).unwrap();
document.insert(id, v.get().as_bytes().to_vec().into());
}
}
let mut writer = KvWriterFieldId::memory();
document.into_iter().for_each(|(id, value)| writer.insert(id, value).unwrap());
let new = writer.into_boxed();
match current {
Some(current) => {
let update = Update::create(docid, external_docid, current.boxed(), new);
Ok(Some(DocumentChange::Update(update)))
}
None => {
let insertion = Insertion::create(docid, external_docid, new);
Ok(Some(DocumentChange::Insertion(insertion)))
}
}
}
}
use std::borrow::Borrow;
use serde::Deserialize;
use serde_json::from_str;
use serde_json::value::RawValue;
#[derive(Deserialize)]
pub struct TopLevelMap<'p>(#[serde(borrow)] BTreeMap<CowStr<'p>, &'p RawValue>);
#[derive(Deserialize, PartialEq, Eq, PartialOrd, Ord, Hash, Clone)]
pub struct CowStr<'p>(#[serde(borrow)] Cow<'p, str>);
impl CowStr<'_> {
fn to_string(&self) -> String {
self.0.to_string()
}
}
impl AsRef<str> for CowStr<'_> {
fn as_ref(&self) -> &str {
self.0.as_ref()
}
}
impl<'doc> Borrow<str> for CowStr<'doc> {
fn borrow(&self) -> &str {
self.0.borrow()
}
}
fn get_docid<'p>(
map: &TopLevelMap<'p>,
primary_key: &[&str],
) -> serde_json::Result<Option<CowStr<'p>>> {
match primary_key {
[] => unreachable!("arrrgh"), // would None be ok?
[primary_key] => match map.0.get(*primary_key) {
Some(value) => match from_str::<u64>(value.get()) {
Ok(value) => Ok(Some(CowStr(Cow::Owned(value.to_string())))),
Err(_) => Ok(Some(from_str(value.get())?)),
},
None => Ok(None),
},
[head, tail @ ..] => match map.0.get(*head) {
Some(value) => get_docid(&from_str(value.get())?, tail),
None => Ok(None),
},
}
}