feat: Move the database Deserializer in its own module

src/database/database_view.rs

@@ -1,15 +1,12 @@
-use std::{fmt, marker};
 use std::error::Error;
+use std::marker;
 
 use rocksdb::rocksdb::{DB, Snapshot};
-use rocksdb::rocksdb_options::ReadOptions;
-use serde::de::{DeserializeOwned, Visitor};
-use serde::de::value::MapDeserializer;
-use serde::forward_to_deserialize_any;
+use serde::de::DeserializeOwned;
 
 use crate::index::schema::Schema;
 use crate::blob::positive::PositiveBlob;
-use crate::database::document_key::{DocumentKey, DocumentKeyAttr};
+use crate::database::deserializer::{Deserializer, DeserializerError};
 use crate::database::{DATA_INDEX, DATA_SCHEMA};
 use crate::DocumentId;
 
@@ -83,76 +80,3 @@ where D: DeserializeOwned,
         }
     }
 }
-
-struct Deserializer<'a> {
-    snapshot: &'a Snapshot<&'a DB>,
-    schema: &'a Schema,
-    document_id: DocumentId,
-}
-
-impl<'a> Deserializer<'a> {
-    fn new(snapshot: &'a Snapshot<&DB>, schema: &'a Schema, doc: DocumentId) -> Self {
-        Deserializer { snapshot, schema, document_id: doc }
-    }
-}
-
-impl<'de, 'a, 'b> serde::de::Deserializer<'de> for &'b mut Deserializer<'a> {
-    type Error = DeserializerError;
-
-    fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error>
-    where V: Visitor<'de>
-    {
-        self.deserialize_map(visitor)
-    }
-
-    forward_to_deserialize_any! {
-        bool u8 u16 u32 u64 i8 i16 i32 i64 f32 f64 char str string unit seq
-        bytes byte_buf unit_struct tuple_struct
-        identifier tuple ignored_any option newtype_struct enum
-        struct
-    }
-
-    fn deserialize_map<V>(self, visitor: V) -> Result<V::Value, Self::Error>
-    where V: Visitor<'de>
-    {
-        let mut options = ReadOptions::new();
-        let lower = DocumentKey::new(self.document_id);
-        let upper = DocumentKey::new(self.document_id + 1);
-        options.set_iterate_lower_bound(lower.as_ref());
-        options.set_iterate_upper_bound(upper.as_ref());
-
-        let mut db_iter = self.snapshot.iter_opt(options);
-        let iter = db_iter.map(|(key, value)| {
-            // retrieve the schema attribute name
-            // from the schema attribute number
-            let document_key_attr = DocumentKeyAttr::from_bytes(&key);
-            let schema_attr = document_key_attr.attribute();
-            let attribute_name = self.schema.attribute_name(schema_attr);
-            (attribute_name, value)
-        });
-
-        let map_deserializer = MapDeserializer::new(iter);
-        visitor.visit_map(map_deserializer)
-    }
-}
-
-#[derive(Debug)]
-enum DeserializerError {
-    Custom(String),
-}
-
-impl serde::de::Error for DeserializerError {
-    fn custom<T: fmt::Display>(msg: T) -> Self {
-        DeserializerError::Custom(msg.to_string())
-    }
-}
-
-impl fmt::Display for DeserializerError {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        match self {
-            DeserializerError::Custom(s) => f.write_str(&s),
-        }
-    }
-}
-
-impl Error for DeserializerError {}

src/database/deserializer.rs

@@ -0,0 +1,85 @@
+use std::error::Error;
+use std::fmt;
+
+use rocksdb::rocksdb::{DB, Snapshot};
+use rocksdb::rocksdb_options::ReadOptions;
+use serde::de::value::MapDeserializer;
+use serde::forward_to_deserialize_any;
+use serde::de::Visitor;
+
+use crate::database::document_key::{DocumentKey, DocumentKeyAttr};
+use crate::index::schema::Schema;
+use crate::DocumentId;
+
+pub struct Deserializer<'a> {
+    snapshot: &'a Snapshot<&'a DB>,
+    schema: &'a Schema,
+    document_id: DocumentId,
+}
+
+impl<'a> Deserializer<'a> {
+    pub fn new(snapshot: &'a Snapshot<&DB>, schema: &'a Schema, doc: DocumentId) -> Self {
+        Deserializer { snapshot, schema, document_id: doc }
+    }
+}
+
+impl<'de, 'a, 'b> serde::de::Deserializer<'de> for &'b mut Deserializer<'a> {
+    type Error = DeserializerError;
+
+    fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error>
+    where V: Visitor<'de>
+    {
+        self.deserialize_map(visitor)
+    }
+
+    forward_to_deserialize_any! {
+        bool u8 u16 u32 u64 i8 i16 i32 i64 f32 f64 char str string unit seq
+        bytes byte_buf unit_struct tuple_struct
+        identifier tuple ignored_any option newtype_struct enum
+        struct
+    }
+
+    fn deserialize_map<V>(self, visitor: V) -> Result<V::Value, Self::Error>
+    where V: Visitor<'de>
+    {
+        let mut options = ReadOptions::new();
+        let lower = DocumentKey::new(self.document_id);
+        let upper = DocumentKey::new(self.document_id + 1);
+        options.set_iterate_lower_bound(lower.as_ref());
+        options.set_iterate_upper_bound(upper.as_ref());
+
+        let mut db_iter = self.snapshot.iter_opt(options);
+        let iter = db_iter.map(|(key, value)| {
+            // retrieve the schema attribute name
+            // from the schema attribute number
+            let document_key_attr = DocumentKeyAttr::from_bytes(&key);
+            let schema_attr = document_key_attr.attribute();
+            let attribute_name = self.schema.attribute_name(schema_attr);
+            (attribute_name, value)
+        });
+
+        let map_deserializer = MapDeserializer::new(iter);
+        visitor.visit_map(map_deserializer)
+    }
+}
+
+#[derive(Debug)]
+pub enum DeserializerError {
+    Custom(String),
+}
+
+impl serde::de::Error for DeserializerError {
+    fn custom<T: fmt::Display>(msg: T) -> Self {
+        DeserializerError::Custom(msg.to_string())
+    }
+}
+
+impl fmt::Display for DeserializerError {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        match self {
+            DeserializerError::Custom(s) => f.write_str(&s),
+        }
+    }
+}
+
+impl Error for DeserializerError {}

src/database/mod.rs

@@ -8,6 +8,7 @@ use crate::database::database_view::DatabaseView;
 
 pub mod document_key;
 pub mod database_view;
+mod deserializer;
 
 const DATA_INDEX:  &[u8] = b"data-index";
 const DATA_SCHEMA: &[u8] = b"data-schema";