Extract and write facet databases

milli/src/update/new/channel.rs

@@ -6,6 +6,7 @@ use grenad::Merger;
 use heed::types::Bytes;
 use memmap2::Mmap;
 
+use super::extract::FacetKind;
 use super::StdResult;
 use crate::index::main_key::{DOCUMENTS_IDS_KEY, WORDS_FST_KEY};
 use crate::update::new::KvReaderFieldId;
@@ -120,11 +121,16 @@ pub enum Database {
     WordFidDocids,
     WordPairProximityDocids,
     WordPositionDocids,
+    FacetIdIsNullDocids,
+    FacetIdIsEmptyDocids,
+    FacetIdExistsDocids,
+    FacetIdF64NumberDocids,
+    FacetIdStringDocids,
 }
 
-impl WriterOperation {
+impl Database {
     pub fn database(&self, index: &Index) -> heed::Database<Bytes, Bytes> {
-        match self.database {
+        match self {
             Database::Documents => index.documents.remap_types(),
             Database::ExactWordDocids => index.exact_word_docids.remap_types(),
             Database::Main => index.main.remap_types(),
@@ -133,8 +139,19 @@ impl WriterOperation {
             Database::WordPositionDocids => index.word_position_docids.remap_types(),
             Database::FidWordCountDocids => index.field_id_word_count_docids.remap_types(),
             Database::WordPairProximityDocids => index.word_pair_proximity_docids.remap_types(),
+            Database::FacetIdIsNullDocids => index.facet_id_is_null_docids.remap_types(),
+            Database::FacetIdIsEmptyDocids => index.facet_id_is_empty_docids.remap_types(),
+            Database::FacetIdExistsDocids => index.facet_id_exists_docids.remap_types(),
+            Database::FacetIdF64NumberDocids => index.facet_id_f64_docids.remap_types(),
+            Database::FacetIdStringDocids => index.facet_id_string_docids.remap_types(),
         }
     }
+}
+
+impl WriterOperation {
+    pub fn database(&self, index: &Index) -> heed::Database<Bytes, Bytes> {
+        self.database.database(index)
+    }
 
     pub fn entry(self) -> EntryOperation {
         self.entry
@@ -159,8 +176,12 @@ impl MergerSender {
         MainSender(&self.0)
     }
 
-    pub fn docids<D: DatabaseType>(&self) -> DocidsSender<'_, D> {
+    pub fn docids<D: DatabaseType>(&self) -> WordDocidsSender<'_, D> {
-        DocidsSender { sender: &self.0, _marker: PhantomData }
+        WordDocidsSender { sender: &self.0, _marker: PhantomData }
+    }
+
+    pub fn facet_docids(&self) -> FacetDocidsSender<'_> {
+        FacetDocidsSender { sender: &self.0 }
     }
 
     pub fn documents(&self) -> DocumentsSender<'_> {
@@ -208,16 +229,21 @@ pub enum WordDocids {}
 pub enum WordFidDocids {}
 pub enum WordPairProximityDocids {}
 pub enum WordPositionDocids {}
+pub enum FacetDocids {}
 
 pub trait DatabaseType {
     const DATABASE: Database;
+}
 
+pub trait MergerOperationType {
     fn new_merger_operation(merger: Merger<File, MergeDeladdCboRoaringBitmaps>) -> MergerOperation;
 }
 
 impl DatabaseType for ExactWordDocids {
     const DATABASE: Database = Database::ExactWordDocids;
+}
 
+impl MergerOperationType for ExactWordDocids {
     fn new_merger_operation(merger: Merger<File, MergeDeladdCboRoaringBitmaps>) -> MergerOperation {
         MergerOperation::ExactWordDocidsMerger(merger)
     }
@@ -225,7 +251,9 @@ impl DatabaseType for ExactWordDocids {
 
 impl DatabaseType for FidWordCountDocids {
     const DATABASE: Database = Database::FidWordCountDocids;
+}
 
+impl MergerOperationType for FidWordCountDocids {
     fn new_merger_operation(merger: Merger<File, MergeDeladdCboRoaringBitmaps>) -> MergerOperation {
         MergerOperation::FidWordCountDocidsMerger(merger)
     }
@@ -233,7 +261,9 @@ impl DatabaseType for FidWordCountDocids {
 
 impl DatabaseType for WordDocids {
     const DATABASE: Database = Database::WordDocids;
+}
 
+impl MergerOperationType for WordDocids {
     fn new_merger_operation(merger: Merger<File, MergeDeladdCboRoaringBitmaps>) -> MergerOperation {
         MergerOperation::WordDocidsMerger(merger)
     }
@@ -241,7 +271,9 @@ impl DatabaseType for WordDocids {
 
 impl DatabaseType for WordFidDocids {
     const DATABASE: Database = Database::WordFidDocids;
+}
 
+impl MergerOperationType for WordFidDocids {
     fn new_merger_operation(merger: Merger<File, MergeDeladdCboRoaringBitmaps>) -> MergerOperation {
         MergerOperation::WordFidDocidsMerger(merger)
     }
@@ -249,7 +281,9 @@ impl DatabaseType for WordFidDocids {
 
 impl DatabaseType for WordPairProximityDocids {
     const DATABASE: Database = Database::WordPairProximityDocids;
+}
 
+impl MergerOperationType for WordPairProximityDocids {
     fn new_merger_operation(merger: Merger<File, MergeDeladdCboRoaringBitmaps>) -> MergerOperation {
         MergerOperation::WordPairProximityDocidsMerger(merger)
     }
@@ -257,19 +291,32 @@ impl DatabaseType for WordPairProximityDocids {
 
 impl DatabaseType for WordPositionDocids {
     const DATABASE: Database = Database::WordPositionDocids;
+}
 
+impl MergerOperationType for WordPositionDocids {
     fn new_merger_operation(merger: Merger<File, MergeDeladdCboRoaringBitmaps>) -> MergerOperation {
         MergerOperation::WordPositionDocidsMerger(merger)
     }
 }
 
-pub struct DocidsSender<'a, D> {
+impl MergerOperationType for FacetDocids {
+    fn new_merger_operation(merger: Merger<File, MergeDeladdCboRoaringBitmaps>) -> MergerOperation {
+        MergerOperation::FacetDocidsMerger(merger)
+    }
+}
+
+pub trait DocidsSender {
+    fn write(&self, key: &[u8], value: &[u8]) -> StdResult<(), SendError<()>>;
+    fn delete(&self, key: &[u8]) -> StdResult<(), SendError<()>>;
+}
+
+pub struct WordDocidsSender<'a, D> {
     sender: &'a Sender<WriterOperation>,
     _marker: PhantomData<D>,
 }
 
-impl<D: DatabaseType> DocidsSender<'_, D> {
+impl<D: DatabaseType> DocidsSender for WordDocidsSender<'_, D> {
-    pub fn write(&self, key: &[u8], value: &[u8]) -> StdResult<(), SendError<()>> {
+    fn write(&self, key: &[u8], value: &[u8]) -> StdResult<(), SendError<()>> {
         let entry = EntryOperation::Write(KeyValueEntry::from_small_key_value(key, value));
         match self.sender.send(WriterOperation { database: D::DATABASE, entry }) {
             Ok(()) => Ok(()),
@@ -277,7 +324,7 @@ impl<D: DatabaseType> DocidsSender<'_, D> {
         }
     }
 
-    pub fn delete(&self, key: &[u8]) -> StdResult<(), SendError<()>> {
+    fn delete(&self, key: &[u8]) -> StdResult<(), SendError<()>> {
         let entry = EntryOperation::Delete(KeyEntry::from_key(key));
         match self.sender.send(WriterOperation { database: D::DATABASE, entry }) {
             Ok(()) => Ok(()),
@@ -286,6 +333,43 @@ impl<D: DatabaseType> DocidsSender<'_, D> {
     }
 }
 
+pub struct FacetDocidsSender<'a> {
+    sender: &'a Sender<WriterOperation>,
+}
+
+impl DocidsSender for FacetDocidsSender<'_> {
+    fn write(&self, key: &[u8], value: &[u8]) -> StdResult<(), SendError<()>> {
+        let (database, key) = self.extract_database(key);
+        let entry = EntryOperation::Write(KeyValueEntry::from_small_key_value(key, value));
+        match self.sender.send(WriterOperation { database, entry }) {
+            Ok(()) => Ok(()),
+            Err(SendError(_)) => Err(SendError(())),
+        }
+    }
+
+    fn delete(&self, key: &[u8]) -> StdResult<(), SendError<()>> {
+        let (database, key) = self.extract_database(key);
+        let entry = EntryOperation::Delete(KeyEntry::from_key(key));
+        match self.sender.send(WriterOperation { database, entry }) {
+            Ok(()) => Ok(()),
+            Err(SendError(_)) => Err(SendError(())),
+        }
+    }
+}
+
+impl FacetDocidsSender<'_> {
+    fn extract_database<'a>(&self, key: &'a [u8]) -> (Database, &'a [u8]) {
+        let database = match FacetKind::from(key[0]) {
+            FacetKind::Number => Database::FacetIdF64NumberDocids,
+            FacetKind::String => Database::FacetIdStringDocids,
+            FacetKind::Null => Database::FacetIdIsNullDocids,
+            FacetKind::Empty => Database::FacetIdIsEmptyDocids,
+            FacetKind::Exists => Database::FacetIdExistsDocids,
+        };
+        (database, &key[1..])
+    }
+}
+
 pub struct DocumentsSender<'a>(&'a Sender<WriterOperation>);
 
 impl DocumentsSender<'_> {
@@ -321,6 +405,7 @@ pub enum MergerOperation {
     WordFidDocidsMerger(Merger<File, MergeDeladdCboRoaringBitmaps>),
     WordPairProximityDocidsMerger(Merger<File, MergeDeladdCboRoaringBitmaps>),
     WordPositionDocidsMerger(Merger<File, MergeDeladdCboRoaringBitmaps>),
+    FacetDocidsMerger(Merger<File, MergeDeladdCboRoaringBitmaps>),
     DeleteDocument { docid: DocumentId },
     InsertDocument { docid: DocumentId, document: Box<KvReaderFieldId> },
     FinishedDocument,
@@ -344,7 +429,7 @@ impl ExtractorSender {
         DocumentSender(&self.0)
     }
 
-    pub fn send_searchable<D: DatabaseType>(
+    pub fn send_searchable<D: MergerOperationType>(
         &self,
         merger: Merger<File, MergeDeladdCboRoaringBitmaps>,
     ) -> StdResult<(), SendError<()>> {

milli/src/update/new/extract/faceted/extract_facets.rs

@@ -1,61 +1,180 @@
 use std::collections::HashSet;
+use std::fmt::Debug;
+use std::fs::File;
 
+use grenad::{MergeFunction, Merger};
 use heed::RoTxn;
+use rayon::iter::{IntoParallelIterator, ParallelBridge, ParallelIterator};
 use serde_json::Value;
 
-use super::FacetedExtractor;
+use super::super::cache::CboCachedSorter;
+use super::facet_document::extract_document_facets;
+use super::FacetKind;
 use crate::facet::value_encoding::f64_into_bytes;
-use crate::{normalize_facet, FieldId, Index, Result, MAX_FACET_VALUE_LENGTH};
+use crate::update::new::extract::DocidsExtractor;
+use crate::update::new::{DocumentChange, ItemsPool};
+use crate::update::{create_sorter, GrenadParameters, MergeDeladdCboRoaringBitmaps};
+use crate::{DocumentId, FieldId, GlobalFieldsIdsMap, Index, Result, MAX_FACET_VALUE_LENGTH};
+pub struct FacetedDocidsExtractor;
 
-pub struct FieldIdFacetNumberDocidsExtractor;
+impl FacetedDocidsExtractor {
+    fn extract_document_change(
+        rtxn: &RoTxn,
+        index: &Index,
+        buffer: &mut Vec<u8>,
+        fields_ids_map: &mut GlobalFieldsIdsMap,
+        attributes_to_extract: &[&str],
+        cached_sorter: &mut CboCachedSorter<MergeDeladdCboRoaringBitmaps>,
+        document_change: DocumentChange,
+    ) -> Result<()> {
+        match document_change {
+            DocumentChange::Deletion(inner) => extract_document_facets(
+                attributes_to_extract,
+                inner.current(rtxn, index)?.unwrap(),
+                fields_ids_map,
+                &mut |fid, value| {
+                    Self::facet_fn_with_options(
+                        buffer,
+                        cached_sorter,
+                        CboCachedSorter::insert_del_u32,
+                        inner.docid(),
+                        fid,
+                        value,
+                    )
+                },
+            ),
+            DocumentChange::Update(inner) => {
+                extract_document_facets(
+                    attributes_to_extract,
+                    inner.current(rtxn, index)?.unwrap(),
+                    fields_ids_map,
+                    &mut |fid, value| {
+                        Self::facet_fn_with_options(
+                            buffer,
+                            cached_sorter,
+                            CboCachedSorter::insert_del_u32,
+                            inner.docid(),
+                            fid,
+                            value,
+                        )
+                    },
+                )?;
+
+                extract_document_facets(
+                    attributes_to_extract,
+                    inner.new(),
+                    fields_ids_map,
+                    &mut |fid, value| {
+                        Self::facet_fn_with_options(
+                            buffer,
+                            cached_sorter,
+                            CboCachedSorter::insert_add_u32,
+                            inner.docid(),
+                            fid,
+                            value,
+                        )
+                    },
+                )
+            }
+            DocumentChange::Insertion(inner) => extract_document_facets(
+                attributes_to_extract,
+                inner.new(),
+                fields_ids_map,
+                &mut |fid, value| {
+                    Self::facet_fn_with_options(
+                        buffer,
+                        cached_sorter,
+                        CboCachedSorter::insert_add_u32,
+                        inner.docid(),
+                        fid,
+                        value,
+                    )
+                },
+            ),
+        }
+    }
+
+    fn facet_fn_with_options<MF>(
+        buffer: &mut Vec<u8>,
+        cached_sorter: &mut CboCachedSorter<MF>,
+        cache_fn: impl Fn(&mut CboCachedSorter<MF>, &[u8], u32) -> grenad::Result<(), MF::Error>,
+        docid: DocumentId,
+        fid: FieldId,
+        value: &Value,
+    ) -> Result<()>
+    where
+        MF: MergeFunction,
+        MF::Error: Debug,
+        grenad::Error<MF::Error>: Into<crate::Error>,
+    {
+        // Exists
+        // key: fid
+        buffer.clear();
+        buffer.push(FacetKind::Exists as u8);
+        buffer.extend_from_slice(&fid.to_be_bytes());
+        cache_fn(cached_sorter, &*buffer, docid).map_err(Into::into)?;
+
+        match value {
+            // Number
+            // key: fid - level - orderedf64 - orignalf64
+            Value::Number(number) => {
+                if let Some((n, ordered)) =
+                    number.as_f64().and_then(|n| f64_into_bytes(n).map(|ordered| (n, ordered)))
+                {
+                    buffer.clear();
+                    buffer.push(FacetKind::Number as u8);
+                    buffer.extend_from_slice(&fid.to_be_bytes());
+                    buffer.push(1); // level 0
+                    buffer.extend_from_slice(&ordered);
+                    buffer.extend_from_slice(&n.to_be_bytes());
+
+                    cache_fn(cached_sorter, &*buffer, docid).map_err(Into::into)
+                } else {
+                    Ok(())
+                }
+            }
+            // String
+            // key: fid - level - truncated_string
+            Value::String(s) => {
+                let truncated = truncate_str(s);
+                buffer.clear();
+                buffer.push(FacetKind::String as u8);
+                buffer.extend_from_slice(&fid.to_be_bytes());
+                buffer.push(1); // level 0
+                buffer.extend_from_slice(truncated.as_bytes());
+                cache_fn(cached_sorter, &*buffer, docid).map_err(Into::into)
+            }
+            // Null
+            // key: fid
+            Value::Null => {
+                buffer.clear();
+                buffer.push(FacetKind::Null as u8);
+                buffer.extend_from_slice(&fid.to_be_bytes());
+                cache_fn(cached_sorter, &*buffer, docid).map_err(Into::into)
+            }
+            // Empty
+            // key: fid
+            Value::Array(a) if a.is_empty() => {
+                buffer.clear();
+                buffer.push(FacetKind::Empty as u8);
+                buffer.extend_from_slice(&fid.to_be_bytes());
+                cache_fn(cached_sorter, &*buffer, docid).map_err(Into::into)
+            }
+            Value::Object(o) if o.is_empty() => {
+                buffer.clear();
+                buffer.push(FacetKind::Empty as u8);
+                buffer.extend_from_slice(&fid.to_be_bytes());
+                cache_fn(cached_sorter, &*buffer, docid).map_err(Into::into)
+            }
+            // Otherwise, do nothing
+            /// TODO: What about Value::Bool?
+            _ => Ok(()),
+        }
+    }
 
-impl FacetedExtractor for FieldIdFacetNumberDocidsExtractor {
     fn attributes_to_extract<'a>(rtxn: &'a RoTxn, index: &'a Index) -> Result<HashSet<String>> {
         index.user_defined_faceted_fields(rtxn)
     }
-
-    fn build_key<'b>(
-        field_id: FieldId,
-        value: &Value,
-        output: &'b mut Vec<u8>,
-    ) -> Option<&'b [u8]> {
-        let number = value.as_number()?;
-        let n = number.as_f64()?;
-        let ordered = f64_into_bytes(n)?;
-
-        // fid - level - orderedf64 - orignalf64
-        output.extend_from_slice(&field_id.to_be_bytes());
-        output.push(1); // level 0
-        output.extend_from_slice(&ordered);
-        output.extend_from_slice(&n.to_be_bytes());
-
-        Some(&*output)
-    }
-}
-
-pub struct FieldIdFacetStringDocidsExtractor;
-
-impl FacetedExtractor for FieldIdFacetStringDocidsExtractor {
-    fn attributes_to_extract<'a>(rtxn: &'a RoTxn, index: &'a Index) -> Result<HashSet<String>> {
-        index.user_defined_faceted_fields(rtxn)
-    }
-
-    fn build_key<'b>(
-        field_id: FieldId,
-        value: &Value,
-        output: &'b mut Vec<u8>,
-    ) -> Option<&'b [u8]> {
-        let string = value.as_str()?;
-        let normalize = normalize_facet(string);
-        let truncated = truncate_str(&normalize);
-
-        // fid - level - normalized string
-        output.extend_from_slice(&field_id.to_be_bytes());
-        output.push(1); // level 0
-        output.extend_from_slice(truncated.as_bytes());
-
-        Some(&*output)
-    }
 }
 
 /// Truncates a string to the biggest valid LMDB key size.
@@ -70,68 +189,77 @@ fn truncate_str(s: &str) -> &str {
     &s[..index.unwrap_or(0)]
 }
 
-pub struct FieldIdFacetIsNullDocidsExtractor;
+impl DocidsExtractor for FacetedDocidsExtractor {
+    #[tracing::instrument(level = "trace", skip_all, target = "indexing::extract::faceted")]
+    fn run_extraction(
+        index: &Index,
+        fields_ids_map: &GlobalFieldsIdsMap,
+        indexer: GrenadParameters,
+        document_changes: impl IntoParallelIterator<Item = Result<DocumentChange>>,
+    ) -> Result<Merger<File, MergeDeladdCboRoaringBitmaps>> {
+        let max_memory = indexer.max_memory_by_thread();
 
-impl FacetedExtractor for FieldIdFacetIsNullDocidsExtractor {
+        let rtxn = index.read_txn()?;
-    fn attributes_to_extract<'a>(rtxn: &'a RoTxn, index: &'a Index) -> Result<HashSet<String>> {
+        let attributes_to_extract = Self::attributes_to_extract(&rtxn, index)?;
-        index.user_defined_faceted_fields(rtxn)
+        let attributes_to_extract: Vec<_> =
+            attributes_to_extract.iter().map(|s| s.as_ref()).collect();
+
+        let context_pool = ItemsPool::new(|| {
+            Ok((
+                index.read_txn()?,
+                fields_ids_map.clone(),
+                Vec::new(),
+                CboCachedSorter::new(
+                    // TODO use a better value
+                    100.try_into().unwrap(),
+                    create_sorter(
+                        grenad::SortAlgorithm::Stable,
+                        MergeDeladdCboRoaringBitmaps,
+                        indexer.chunk_compression_type,
+                        indexer.chunk_compression_level,
+                        indexer.max_nb_chunks,
+                        max_memory,
+                    ),
+                ),
+            ))
+        });
+
+        {
+            let span =
+                tracing::trace_span!(target: "indexing::documents::extract", "docids_extraction");
+            let _entered = span.enter();
+            document_changes.into_par_iter().try_for_each(|document_change| {
+                context_pool.with(|(rtxn, fields_ids_map, buffer, cached_sorter)| {
+                    Self::extract_document_change(
+                        &*rtxn,
+                        index,
+                        buffer,
+                        fields_ids_map,
+                        &attributes_to_extract,
+                        cached_sorter,
+                        document_change?,
+                    )
+                })
+            })?;
         }
+        {
+            let mut builder = grenad::MergerBuilder::new(MergeDeladdCboRoaringBitmaps);
+            let span =
+                tracing::trace_span!(target: "indexing::documents::extract", "merger_building");
+            let _entered = span.enter();
 
-    fn build_key<'b>(
+            let readers: Vec<_> = context_pool
-        field_id: FieldId,
+                .into_items()
-        value: &Value,
+                .par_bridge()
-        output: &'b mut Vec<u8>,
+                .map(|(_rtxn, _tokenizer, _fields_ids_map, cached_sorter)| {
-    ) -> Option<&'b [u8]> {
+                    let sorter = cached_sorter.into_sorter()?;
-        if value.is_null() {
+                    sorter.into_reader_cursors()
-            output.extend_from_slice(&field_id.to_be_bytes());
+                })
-            Some(&*output)
+                .collect();
-        } else {
+            for reader in readers {
-            None
+                builder.extend(reader?);
-        }
+            }
-    }
+            Ok(builder.build())
-}
-
-pub struct FieldIdFacetExistsDocidsExtractor;
-
-impl FacetedExtractor for FieldIdFacetExistsDocidsExtractor {
-    fn attributes_to_extract<'a>(rtxn: &'a RoTxn, index: &'a Index) -> Result<HashSet<String>> {
-        index.user_defined_faceted_fields(rtxn)
-    }
-
-    fn build_key<'b>(
-        field_id: FieldId,
-        _value: &Value,
-        output: &'b mut Vec<u8>,
-    ) -> Option<&'b [u8]> {
-        output.extend_from_slice(&field_id.to_be_bytes());
-        Some(&*output)
-    }
-}
-
-pub struct FieldIdFacetIsEmptyDocidsExtractor;
-
-impl FacetedExtractor for FieldIdFacetIsEmptyDocidsExtractor {
-    fn attributes_to_extract<'a>(rtxn: &'a RoTxn, index: &'a Index) -> Result<HashSet<String>> {
-        index.user_defined_faceted_fields(rtxn)
-    }
-
-    fn build_key<'b>(
-        field_id: FieldId,
-        value: &Value,
-        output: &'b mut Vec<u8>,
-    ) -> Option<&'b [u8]> {
-        let is_empty = match value {
-            Value::Null | Value::Bool(_) | Value::Number(_) => false,
-            Value::String(s) => s.is_empty(),
-            Value::Array(a) => a.is_empty(),
-            Value::Object(o) => o.is_empty(),
-        };
-
-        if is_empty {
-            output.extend_from_slice(&field_id.to_be_bytes());
-            Some(&*output)
-        } else {
-            None
         }
     }
 }

milli/src/update/new/extract/faceted/mod.rs

@@ -1,180 +1,26 @@
-use std::collections::HashSet;
-use std::fmt::Debug;
-use std::fs::File;
-
-pub use extract_facets::*;
-use grenad::{MergeFunction, Merger};
-use heed::RoTxn;
-use rayon::iter::{IntoParallelIterator, ParallelIterator};
-use serde_json::Value;
-
-use super::cache::CboCachedSorter;
-use crate::update::new::{DocumentChange, ItemsPool};
-use crate::update::{create_sorter, GrenadParameters, MergeDeladdCboRoaringBitmaps};
-use crate::{DocumentId, FieldId, GlobalFieldsIdsMap, Index, Result};
-
 mod extract_facets;
 mod facet_document;
 
-pub trait FacetedExtractor {
+pub use extract_facets::FacetedDocidsExtractor;
-    #[tracing::instrument(level = "trace", skip_all, target = "indexing::extract::faceted")]
-    fn run_extraction(
-        index: &Index,
-        fields_ids_map: &GlobalFieldsIdsMap,
-        indexer: GrenadParameters,
-        document_changes: impl IntoParallelIterator<Item = Result<DocumentChange>>,
-    ) -> Result<Merger<File, MergeDeladdCboRoaringBitmaps>> {
-        let max_memory = indexer.max_memory_by_thread();
 
-        let rtxn = index.read_txn()?;
+#[repr(u8)]
-        let attributes_to_extract = Self::attributes_to_extract(&rtxn, index)?;
+pub enum FacetKind {
-        let attributes_to_extract: Vec<_> =
+    Number = 0,
-            attributes_to_extract.iter().map(|s| s.as_ref()).collect();
+    String = 1,
-
+    Null = 2,
-        let context_pool = ItemsPool::new(|| {
+    Empty = 3,
-            Ok((
+    Exists,
-                index.read_txn()?,
+}
-                fields_ids_map.clone(),
+
-                Vec::new(),
+impl From<u8> for FacetKind {
-                CboCachedSorter::new(
+    fn from(value: u8) -> Self {
-                    // TODO use a better value
+        match value {
-                    100.try_into().unwrap(),
+            0 => Self::Number,
-                    create_sorter(
+            1 => Self::String,
-                        grenad::SortAlgorithm::Stable,
+            2 => Self::Null,
-                        MergeDeladdCboRoaringBitmaps,
+            3 => Self::Empty,
-                        indexer.chunk_compression_type,
+            4 => Self::Exists,
-                        indexer.chunk_compression_level,
+            _ => unreachable!(),
-                        indexer.max_nb_chunks,
+        }
-                        max_memory,
+    }
-                    ),
-                ),
-            ))
-        });
-
-        document_changes.into_par_iter().try_for_each(|document_change| {
-            context_pool.with(|(rtxn, fields_ids_map, buffer, cached_sorter)| {
-                Self::extract_document_change(
-                    &*rtxn,
-                    index,
-                    buffer,
-                    fields_ids_map,
-                    &attributes_to_extract,
-                    cached_sorter,
-                    document_change?,
-                )
-            })
-        })?;
-
-        let mut builder = grenad::MergerBuilder::new(MergeDeladdCboRoaringBitmaps);
-        for (_rtxn, _fields_ids_map, _buffer, cache) in context_pool.into_items() {
-            let sorter = cache.into_sorter()?;
-            let readers = sorter.into_reader_cursors()?;
-            builder.extend(readers);
-        }
-
-        Ok(builder.build())
-    }
-
-    // TODO Shorten this
-    fn facet_fn_with_options<MF>(
-        buffer: &mut Vec<u8>,
-        cached_sorter: &mut CboCachedSorter<MF>,
-        cache_fn: impl Fn(&mut CboCachedSorter<MF>, &[u8], u32) -> grenad::Result<(), MF::Error>,
-        docid: DocumentId,
-        fid: FieldId,
-        value: &Value,
-    ) -> Result<()>
-    where
-        MF: MergeFunction,
-        MF::Error: Debug,
-        grenad::Error<MF::Error>: Into<crate::Error>,
-    {
-        buffer.clear();
-        match Self::build_key(fid, value, buffer) {
-            Some(key) => cache_fn(cached_sorter, &key, docid).map_err(Into::into),
-            None => Ok(()),
-        }
-    }
-
-    fn extract_document_change(
-        rtxn: &RoTxn,
-        index: &Index,
-        buffer: &mut Vec<u8>,
-        fields_ids_map: &mut GlobalFieldsIdsMap,
-        attributes_to_extract: &[&str],
-        cached_sorter: &mut CboCachedSorter<MergeDeladdCboRoaringBitmaps>,
-        document_change: DocumentChange,
-    ) -> Result<()> {
-        match document_change {
-            DocumentChange::Deletion(inner) => facet_document::extract_document_facets(
-                attributes_to_extract,
-                inner.current(rtxn, index)?.unwrap(),
-                fields_ids_map,
-                &mut |fid, value| {
-                    Self::facet_fn_with_options(
-                        buffer,
-                        cached_sorter,
-                        CboCachedSorter::insert_del_u32,
-                        inner.docid(),
-                        fid,
-                        value,
-                    )
-                },
-            ),
-            DocumentChange::Update(inner) => {
-                facet_document::extract_document_facets(
-                    attributes_to_extract,
-                    inner.current(rtxn, index)?.unwrap(),
-                    fields_ids_map,
-                    &mut |fid, value| {
-                        Self::facet_fn_with_options(
-                            buffer,
-                            cached_sorter,
-                            CboCachedSorter::insert_del_u32,
-                            inner.docid(),
-                            fid,
-                            value,
-                        )
-                    },
-                )?;
-
-                facet_document::extract_document_facets(
-                    attributes_to_extract,
-                    inner.new(),
-                    fields_ids_map,
-                    &mut |fid, value| {
-                        Self::facet_fn_with_options(
-                            buffer,
-                            cached_sorter,
-                            CboCachedSorter::insert_add_u32,
-                            inner.docid(),
-                            fid,
-                            value,
-                        )
-                    },
-                )
-            }
-            DocumentChange::Insertion(inner) => facet_document::extract_document_facets(
-                attributes_to_extract,
-                inner.new(),
-                fields_ids_map,
-                &mut |fid, value| {
-                    Self::facet_fn_with_options(
-                        buffer,
-                        cached_sorter,
-                        CboCachedSorter::insert_add_u32,
-                        inner.docid(),
-                        fid,
-                        value,
-                    )
-                },
-            ),
-        }
-    }
-
-    // TODO avoid owning the strings here.
-    fn attributes_to_extract<'a>(rtxn: &'a RoTxn, index: &'a Index) -> Result<HashSet<String>>;
-
-    fn build_key<'b>(field_id: FieldId, value: &Value, output: &'b mut Vec<u8>)
-        -> Option<&'b [u8]>;
 }

milli/src/update/new/extract/mod.rs

@@ -2,9 +2,29 @@ mod cache;
 mod faceted;
 mod searchable;
 
+use std::fs::File;
+
 pub use faceted::*;
+use grenad::Merger;
+use rayon::iter::IntoParallelIterator;
 pub use searchable::*;
 
+use crate::{
+    update::{GrenadParameters, MergeDeladdCboRoaringBitmaps},
+    GlobalFieldsIdsMap, Index, Result,
+};
+
+use super::DocumentChange;
+
+pub trait DocidsExtractor {
+    fn run_extraction(
+        index: &Index,
+        fields_ids_map: &GlobalFieldsIdsMap,
+        indexer: GrenadParameters,
+        document_changes: impl IntoParallelIterator<Item = Result<DocumentChange>>,
+    ) -> Result<Merger<File, MergeDeladdCboRoaringBitmaps>>;
+}
+
 /// TODO move in permissive json pointer
 pub mod perm_json_p {
     use serde_json::{Map, Value};
@@ -39,6 +59,10 @@ pub mod perm_json_p {
         base_key: &str,
         seeker: &mut impl FnMut(&str, &Value) -> Result<()>,
     ) -> Result<()> {
+        if value.is_empty() {
+            seeker(&base_key, &Value::Object(Map::with_capacity(0)))?;
+        }
+
         for (key, value) in value.iter() {
             let base_key = if base_key.is_empty() {
                 key.to_string()
@@ -80,6 +104,10 @@ pub mod perm_json_p {
         base_key: &str,
         seeker: &mut impl FnMut(&str, &Value) -> Result<()>,
     ) -> Result<()> {
+        if values.is_empty() {
+            seeker(&base_key, &Value::Array(vec![]))?;
+        }
+
         for value in values {
             match value {
                 Value::Object(object) => {

milli/src/update/new/extract/searchable/mod.rs

@@ -17,6 +17,7 @@ use rayon::iter::{IntoParallelIterator, ParallelBridge, ParallelIterator};
 use tokenize_document::{tokenizer_builder, DocumentTokenizer};
 
 use super::cache::CboCachedSorter;
+use super::DocidsExtractor;
 use crate::update::new::{DocumentChange, ItemsPool};
 use crate::update::{create_sorter, GrenadParameters, MergeDeladdCboRoaringBitmaps};
 use crate::{GlobalFieldsIdsMap, Index, Result, MAX_POSITION_PER_ATTRIBUTE};
@@ -130,3 +131,14 @@ pub trait SearchableExtractor {
 
     fn attributes_to_skip<'a>(rtxn: &'a RoTxn, index: &'a Index) -> Result<Vec<&'a str>>;
 }
+
+impl<T: SearchableExtractor> DocidsExtractor for T {
+    fn run_extraction(
+        index: &Index,
+        fields_ids_map: &GlobalFieldsIdsMap,
+        indexer: GrenadParameters,
+        document_changes: impl IntoParallelIterator<Item = Result<DocumentChange>>,
+    ) -> Result<Merger<File, MergeDeladdCboRoaringBitmaps>> {
+        Self::run_extraction(index, fields_ids_map, indexer, document_changes)
+    }
+}

milli/src/update/new/indexer/mod.rs

@@ -101,6 +101,22 @@ where
                         max_memory: Some(max_memory),
                         ..GrenadParameters::default()
                     };
+
+                    {
+                        let span = tracing::trace_span!(target: "indexing::documents::extract", "faceted");
+                        let _entered = span.enter();
+                        extract_and_send_docids::<
+                            FacetedDocidsExtractor,
+                            FacetDocids,
+                        >(
+                            index,
+                            &global_fields_ids_map,
+                            grenad_parameters,
+                            document_changes.clone(),
+                            &extractor_sender,
+                        )?;
+                    }
+
                     {
                         let span = tracing::trace_span!(target: "indexing::documents::extract", "word_docids");
                         let _entered = span.enter();
@@ -176,19 +192,19 @@ where
                     }
 
                     // TODO THIS IS TOO MUCH
-                    // Extract fieldid docid facet number
+                    // - [ ] Extract fieldid docid facet number
-                    // Extract fieldid docid facet string
+                    // - [ ] Extract fieldid docid facet string
-                    // Extract facetid string fst
+                    // - [ ] Extract facetid string fst
-                    // Extract facetid normalized string strings
+                    // - [ ] Extract facetid normalized string strings
 
                     // TODO Inverted Indexes again
-                    // Extract fieldid facet isempty docids
+                    // - [x] Extract fieldid facet isempty docids
-                    // Extract fieldid facet isnull docids
+                    // - [x] Extract fieldid facet isnull docids
-                    // Extract fieldid facet exists docids
+                    // - [x] Extract fieldid facet exists docids
 
                     // TODO This is the normal system
-                    // Extract fieldid facet number docids
+                    // - [x] Extract fieldid facet number docids
-                    // Extract fieldid facet string docids
+                    // - [x] Extract fieldid facet string docids
 
                     Ok(()) as Result<_>
                 })
@@ -238,7 +254,7 @@ where
 /// TODO: GrenadParameters::default() should be removed in favor a passed parameter
 /// TODO: manage the errors correctly
 /// TODO: we must have a single trait that also gives the extractor type
-fn extract_and_send_docids<E: SearchableExtractor, D: DatabaseType>(
+fn extract_and_send_docids<E: DocidsExtractor, D: MergerOperationType>(
     index: &Index,
     fields_ids_map: &GlobalFieldsIdsMap,
     indexer: GrenadParameters,

milli/src/update/new/merger.rs

@@ -12,6 +12,7 @@ use tempfile::tempfile;
 
 use super::channel::*;
 use super::{Deletion, DocumentChange, Insertion, KvReaderDelAdd, KvReaderFieldId, Update};
+use super::extract::FacetKind;
 use crate::update::del_add::DelAdd;
 use crate::update::new::channel::MergerOperation;
 use crate::update::MergeDeladdCboRoaringBitmaps;
@@ -63,11 +64,12 @@ pub fn merge_grenad_entries(
                 )?;
             }
             MergerOperation::WordDocidsMerger(merger) => {
+                let mut add_words_fst = SetBuilder::new(BufWriter::new(tempfile()?))?;
+                let mut del_words_fst = SetBuilder::new(BufWriter::new(tempfile()?))?;
+                {
                     let span =
                         tracing::trace_span!(target: "indexing::documents::merge", "word_docids");
                     let _entered = span.enter();
-                let mut add_words_fst = SetBuilder::new(BufWriter::new(tempfile()?))?;
-                let mut del_words_fst = SetBuilder::new(BufWriter::new(tempfile()?))?;
 
                     merge_and_send_docids(
                         merger,
@@ -78,12 +80,18 @@ pub fn merge_grenad_entries(
                         |key| add_words_fst.insert(key),
                         |key| del_words_fst.insert(key),
                     )?;
+                }
 
+                {
+                    let span =
+                        tracing::trace_span!(target: "indexing::documents::merge", "words_fst");
+                    let _entered = span.enter();
                     // Move that into a dedicated function
                     let words_fst = index.words_fst(rtxn)?;
                     let mmap = compute_new_words_fst(add_words_fst, del_words_fst, words_fst)?;
                     sender.main().write_words_fst(mmap).unwrap();
                 }
+            }
             MergerOperation::WordFidDocidsMerger(merger) => {
                 let span =
                     tracing::trace_span!(target: "indexing::documents::merge", "word_fid_docids");
@@ -161,6 +169,18 @@ pub fn merge_grenad_entries(
             MergerOperation::FinishedDocument => {
                 // send the rtree
             }
+            MergerOperation::FacetDocidsMerger(merger) => {
+                let span =
+                    tracing::trace_span!(target: "indexing::documents::merge", "facet_docids");
+                let _entered = span.enter();
+                merge_and_send_facet_docids(
+                    merger,
+                    FacetDatabases::new(index),
+                    rtxn,
+                    &mut buffer,
+                    sender.facet_docids(),
+                )?;
+            }
         }
     }
 
@@ -252,12 +272,12 @@ fn compute_new_words_fst(
 }
 
 #[tracing::instrument(level = "trace", skip_all, target = "indexing::merge")]
-fn merge_and_send_docids<D: DatabaseType>(
+fn merge_and_send_docids(
     merger: Merger<File, MergeDeladdCboRoaringBitmaps>,
     database: Database<Bytes, Bytes>,
     rtxn: &RoTxn<'_>,
     buffer: &mut Vec<u8>,
-    word_docids_sender: DocidsSender<'_, D>,
+    docids_sender: impl DocidsSender,
     mut add_key: impl FnMut(&[u8]) -> fst::Result<()>,
     mut del_key: impl FnMut(&[u8]) -> fst::Result<()>,
 ) -> Result<()> {
@@ -271,11 +291,11 @@ fn merge_and_send_docids<D: DatabaseType>(
         match merge_cbo_bitmaps(current, del, add)? {
             Operation::Write(bitmap) => {
                 let value = cbo_bitmap_serialize_into_vec(&bitmap, buffer);
-                word_docids_sender.write(key, value).unwrap();
+                docids_sender.write(key, value).unwrap();
                 add_key(key)?;
             }
             Operation::Delete => {
-                word_docids_sender.delete(key).unwrap();
+                docids_sender.delete(key).unwrap();
                 del_key(key)?;
             }
             Operation::Ignore => (),
@@ -285,6 +305,76 @@ fn merge_and_send_docids<D: DatabaseType>(
     Ok(())
 }
 
+#[tracing::instrument(level = "trace", skip_all, target = "indexing::merge")]
+fn merge_and_send_facet_docids(
+    merger: Merger<File, MergeDeladdCboRoaringBitmaps>,
+    database: FacetDatabases,
+    rtxn: &RoTxn<'_>,
+    buffer: &mut Vec<u8>,
+    docids_sender: impl DocidsSender,
+) -> Result<()> {
+    let mut merger_iter = merger.into_stream_merger_iter().unwrap();
+    while let Some((key, deladd)) = merger_iter.next().unwrap() {
+        let current = database.get(rtxn, key)?;
+        let deladd: &KvReaderDelAdd = deladd.into();
+        let del = deladd.get(DelAdd::Deletion);
+        let add = deladd.get(DelAdd::Addition);
+
+        match merge_cbo_bitmaps(current, del, add)? {
+            Operation::Write(bitmap) => {
+                let value = cbo_bitmap_serialize_into_vec(&bitmap, buffer);
+                docids_sender.write(key, value).unwrap();
+            }
+            Operation::Delete => {
+                docids_sender.delete(key).unwrap();
+            }
+            Operation::Ignore => (),
+        }
+    }
+
+    Ok(())
+}
+
+struct FacetDatabases {
+    /// Maps the facet field id and the docids for which this field exists
+    facet_id_exists_docids: Database<Bytes, Bytes>,
+    /// Maps the facet field id and the docids for which this field is set as null
+    facet_id_is_null_docids: Database<Bytes, Bytes>,
+    /// Maps the facet field id and the docids for which this field is considered empty
+    facet_id_is_empty_docids: Database<Bytes, Bytes>,
+    /// Maps the facet field id and ranges of numbers with the docids that corresponds to them.
+    facet_id_f64_docids: Database<Bytes, Bytes>,
+    /// Maps the facet field id and ranges of strings with the docids that corresponds to them.
+    facet_id_string_docids: Database<Bytes, Bytes>,
+}
+
+impl FacetDatabases {
+    fn new(index: &Index) -> Self {
+        Self {
+            facet_id_exists_docids: index.facet_id_exists_docids.remap_types(),
+            facet_id_is_null_docids: index.facet_id_is_null_docids.remap_types(),
+            facet_id_is_empty_docids: index.facet_id_is_empty_docids.remap_types(),
+            facet_id_f64_docids: index.facet_id_f64_docids.remap_types(),
+            facet_id_string_docids: index.facet_id_string_docids.remap_types(),
+        }
+    }
+
+    fn get<'a>(&self, rtxn: &'a RoTxn<'_>, key: &[u8]) -> heed::Result<Option<&'a [u8]>> {
+        let (facet_kind, key) = self.extract_facet_kind(key);
+        match facet_kind {
+            FacetKind::Exists => self.facet_id_exists_docids.get(rtxn, key),
+            FacetKind::Null => self.facet_id_is_null_docids.get(rtxn, key),
+            FacetKind::Empty => self.facet_id_is_empty_docids.get(rtxn, key),
+            FacetKind::Number => self.facet_id_f64_docids.get(rtxn, key),
+            FacetKind::String => self.facet_id_string_docids.get(rtxn, key),
+        }
+    }
+
+    fn extract_facet_kind<'a>(&self, key: &'a [u8]) -> (FacetKind, &'a [u8]) {
+        (FacetKind::from(key[0]), &key[1..])
+    }
+}
+
 enum Operation {
     Write(RoaringBitmap),
     Delete,