Add the criteria list to the index

src/criterion.rs

@@ -1,3 +1,8 @@
+use crate::FieldId;
+
+use serde::{Serialize, Deserialize};
+
+#[derive(Debug, Serialize, Deserialize, Copy, Clone, PartialEq, Eq)]
 pub enum Criterion {
     /// Sorted by increasing number of typos.
     Typo,
@@ -14,9 +19,9 @@ pub enum Criterion {
     /// Sorted by the similarity of the matched words with the query words.
     Exactness,
     /// Sorted by the increasing value of the field specified.
-    CustomAsc(String),
+    Asc(FieldId),
     /// Sorted by the decreasing value of the field specified.
-    CustomDesc(String),
+    Desc(FieldId),
 }
 
 pub fn default_criteria() -> Vec<Criterion> {

src/index.rs

@@ -9,13 +9,14 @@ use roaring::RoaringBitmap;
 
 use crate::facet::FacetType;
 use crate::fields_ids_map::FieldsIdsMap;
-use crate::Search;
+use crate::{default_criteria, Criterion, Search};
 use crate::{BEU32, DocumentId, FieldId, ExternalDocumentsIds};
 use crate::{
     RoaringBitmapCodec, BEU32StrCodec, StrStrU8Codec, ObkvCodec,
     BoRoaringBitmapCodec, CboRoaringBitmapCodec,
 };
 
+pub const CRITERIA_KEY: &str = "criteria";
 pub const DISPLAYED_FIELDS_KEY: &str = "displayed-fields";
 pub const DOCUMENTS_IDS_KEY: &str = "documents-ids";
 pub const FACETED_DOCUMENTS_IDS_PREFIX: &str = "faceted-documents-ids";
@@ -246,6 +247,23 @@ impl Index {
         }
     }
 
+    /* criteria */
+
+    pub fn put_criteria(&self, wtxn: &mut RwTxn, criteria: &[Criterion]) -> heed::Result<()> {
+        self.main.put::<_, Str, SerdeJson<&[Criterion]>>(wtxn, CRITERIA_KEY, &criteria)
+    }
+
+    pub fn delete_criteria(&self, wtxn: &mut RwTxn) -> heed::Result<bool> {
+        self.main.delete::<_, Str>(wtxn, CRITERIA_KEY)
+    }
+
+    pub fn criteria(&self, rtxn: &RoTxn) -> heed::Result<Vec<Criterion>> {
+        match self.main.get::<_, Str, SerdeJson<Vec<Criterion>>>(rtxn, CRITERIA_KEY)? {
+            Some(criteria) => Ok(criteria),
+            None => Ok(default_criteria()),
+        }
+    }
+
     /* words fst */
 
     /// Writes the FST which is the words dictionnary of the engine.