Avoid cloning strings

src/core/database/json/mod.rs

@@ -10,7 +10,7 @@ use crate::core::{
     database::{IDatabase, LoadError, SaveError},
 };
 
-use super::serde::Database;
+use super::serde::{deserialize::DeserializeDatabase, serialize::SerializeDatabase};
 
 impl From<serde_json::Error> for LoadError {
     fn from(err: serde_json::Error) -> LoadError {
@@ -50,12 +50,12 @@ impl<JDB: IJsonDatabaseBackend> JsonDatabase<JDB> {
 impl<JDB: IJsonDatabaseBackend> IDatabase for JsonDatabase<JDB> {
     fn load(&self) -> Result<Collection, LoadError> {
         let serialized = self.backend.read()?;
-        let database: Database = serde_json::from_str(&serialized)?;
+        let database: DeserializeDatabase = serde_json::from_str(&serialized)?;
         database.try_into()
     }
 
     fn save(&mut self, collection: &Collection) -> Result<(), SaveError> {
-        let database: Database = collection.into();
+        let database: SerializeDatabase = collection.into();
         let serialized = serde_json::to_string(&database)?;
         self.backend.write(&serialized)?;
         Ok(())
@@ -135,7 +135,7 @@ mod tests {
     #[test]
     fn load_errors() {
         let json = String::from("");
-        let serde_err = serde_json::from_str::<Database>(&json);
+        let serde_err = serde_json::from_str::<DeserializeDatabase>(&json);
         assert!(serde_err.is_err());
 
         let serde_err: LoadError = serde_err.unwrap_err().into();

src/core/database/serde/deserialize.rs

@@ -1,3 +1,7 @@
+use std::collections::HashMap;
+
+use serde::Deserialize;
+
 use crate::{
     collection::{
         self,
@@ -5,17 +9,24 @@ use crate::{
     },
     core::{
         collection::{artist::Artist, Collection},
-        database::{
-            serde::{Database, DbArtist},
-            LoadError,
-        },
+        database::{serde::Database, LoadError},
     },
 };
 
-impl TryFrom<Database> for Collection {
+pub type DeserializeDatabase = Database<DeserializeArtist>;
+
+#[derive(Debug, Deserialize)]
+pub struct DeserializeArtist {
+    name: String,
+    sort: Option<String>,
+    musicbrainz: Option<String>,
+    properties: HashMap<String, Vec<String>>,
+}
+
+impl TryFrom<DeserializeDatabase> for Collection {
     type Error = LoadError;
 
-    fn try_from(database: Database) -> Result<Self, Self::Error> {
+    fn try_from(database: DeserializeDatabase) -> Result<Self, Self::Error> {
         match database {
             Database::V20240210(collection) => collection
                 .into_iter()
@@ -25,15 +36,15 @@ impl TryFrom<Database> for Collection {
     }
 }
 
-impl TryFrom<DbArtist> for Artist {
+impl TryFrom<DeserializeArtist> for Artist {
     type Error = LoadError;
 
-    fn try_from(artist: DbArtist) -> Result<Self, Self::Error> {
+    fn try_from(artist: DeserializeArtist) -> Result<Self, Self::Error> {
         Ok(Artist {
             id: ArtistId::new(artist.name),
             sort: artist.sort.map(ArtistId::new),
             musicbrainz: artist.musicbrainz.map(MusicBrainz::new).transpose()?,
-            properties: artist.properties.into_iter().collect(),
+            properties: artist.properties,
             albums: vec![],
         })
     }

src/core/database/serde/mod.rs

@@ -3,20 +3,9 @@
 pub mod deserialize;
 pub mod serialize;
 
-use std::collections::BTreeMap;
-
 use serde::{Deserialize, Serialize};
 
 #[derive(Debug, Serialize, Deserialize)]
-pub enum Database {
-    V20240210(Vec<DbArtist>),
-}
-
-// FIXME: try with references to original values.
-#[derive(Debug, Serialize, Deserialize)]
-pub struct DbArtist {
-    pub name: String,
-    pub sort: Option<String>,
-    pub musicbrainz: Option<String>,
-    pub properties: BTreeMap<String, Vec<String>>,
+pub enum Database<ARTIST> {
+    V20240210(Vec<ARTIST>),
 }

src/core/database/serde/serialize.rs

@@ -1,21 +1,39 @@
+use std::collections::BTreeMap;
+
+use serde::Serialize;
+
 use crate::core::{
     collection::{artist::Artist, Collection},
-    database::serde::{Database, DbArtist},
+    database::serde::Database,
 };
 
-impl From<&Collection> for Database {
-    fn from(collection: &Collection) -> Self {
+pub type SerializeDatabase<'a> = Database<SerializeArtist<'a>>;
+
+#[derive(Debug, Serialize)]
+pub struct SerializeArtist<'a> {
+    name: &'a str,
+    sort: Option<&'a str>,
+    musicbrainz: Option<&'a str>,
+    properties: BTreeMap<&'a str, &'a Vec<String>>,
+}
+
+impl<'a> From<&'a Collection> for SerializeDatabase<'a> {
+    fn from(collection: &'a Collection) -> Self {
         Database::V20240210(collection.iter().map(|artist| artist.into()).collect())
     }
 }
 
-impl From<&Artist> for DbArtist {
-    fn from(artist: &Artist) -> Self {
-        DbArtist {
-            name: artist.id.name.clone(),
-            sort: artist.sort.clone().map(|id| id.name),
-            musicbrainz: artist.musicbrainz.clone().map(|mb| mb.as_ref().to_owned()),
-            properties: artist.properties.clone().into_iter().collect(),
+impl<'a> From<&'a Artist> for SerializeArtist<'a> {
+    fn from(artist: &'a Artist) -> Self {
+        SerializeArtist {
+            name: &artist.id.name,
+            sort: artist.sort.as_ref().map(|id| id.name.as_ref()),
+            musicbrainz: artist.musicbrainz.as_ref().map(|mb| mb.as_ref()),
+            properties: artist
+                .properties
+                .iter()
+                .map(|(k, v)| (k.as_ref(), v))
+                .collect(),
         }
     }
 }