Use database connection directly

crates/backend/src/lib.rs

@@ -1,11 +1,11 @@
+use db::SqliteConnection;
 use gio::traits::SettingsExt;
 use log::warn;
-use musicus_database::Database;
 use std::{
     cell::{Cell, RefCell},
     path::PathBuf,
     rc::Rc,
-    sync::Arc,
+    sync::{Arc, Mutex},
 };
 use tokio::sync::{broadcast, broadcast::Sender};
 
@@ -59,7 +59,7 @@ pub struct Backend {
     library_updated_sender: Sender<()>,
 
     /// The database. This can be assumed to exist, when the state is set to BackendState::Ready.
-    database: RefCell<Option<Rc<Database>>>,
+    database: RefCell<Option<Arc<Mutex<SqliteConnection>>>>,
 
     /// The player handling playlist and playback. This can be assumed to exist, when the state is
     /// set to BackendState::Ready.

crates/backend/src/library.rs

@@ -1,9 +1,10 @@
 use crate::{Backend, BackendState, Player, Result};
 use gio::prelude::*;
 use log::warn;
-use musicus_database::Database;
+use musicus_database::SqliteConnection;
 use std::path::PathBuf;
 use std::rc::Rc;
+use std::sync::{Arc, Mutex};
 
 impl Backend {
     /// Initialize the music library if it is set in the settings.
@@ -41,8 +42,11 @@ impl Backend {
         let mut db_path = path.clone();
         db_path.push("musicus.db");
 
-        let database = Rc::new(Database::new(db_path.to_str().unwrap())?);
-        self.database.replace(Some(Rc::clone(&database)));
+        let database = Arc::new(Mutex::new(musicus_database::connect(
+            db_path.to_str().unwrap(),
+        )?));
+
+        self.database.replace(Some(database));
 
         let player = Player::new(path);
         self.player.replace(Some(player));
@@ -60,7 +64,7 @@ impl Backend {
     }
 
     /// Get an interface to the database and panic if there is none.
-    pub fn db(&self) -> Rc<Database> {
+    pub fn db(&self) -> Arc<Mutex<SqliteConnection>> {
         self.database.borrow().clone().unwrap()
     }
 

crates/backend/src/player.rs

@@ -1,6 +1,7 @@
 use crate::{Backend, Error, Result};
+use db::Track;
 use glib::clone;
-use musicus_database::Track;
+use musicus_database as db;
 use std::cell::{Cell, RefCell};
 use std::path::PathBuf;
 use std::rc::Rc;
@@ -458,7 +459,7 @@ impl TrackGenerator for RandomTrackGenerator {
     }
 
     fn next(&self) -> Vec<Track> {
-        vec![self.backend.db().random_track().unwrap()]
+        vec![db::random_track(&mut self.backend.db().lock().unwrap()).unwrap()]
     }
 }
 
@@ -479,7 +480,7 @@ impl TrackGenerator for RandomRecordingGenerator {
     }
 
     fn next(&self) -> Vec<Track> {
-        let recording = self.backend.db().random_recording().unwrap();
-        self.backend.db().get_tracks(&recording.id).unwrap()
+        let recording = db::random_recording(&mut self.backend.db().lock().unwrap()).unwrap();
+        db::get_tracks(&mut self.backend.db().lock().unwrap(), &recording.id).unwrap()
     }
 }

crates/database/src/ensembles.rs

@@ -1,9 +1,9 @@
-use super::schema::ensembles;
-use super::{Database, Result};
 use chrono::Utc;
 use diesel::prelude::*;
 use log::info;
 
+use crate::{Result, schema::ensembles, defer_foreign_keys};
+
 /// An ensemble that takes part in recordings.
 #[derive(Insertable, Queryable, PartialEq, Eq, Hash, Debug, Clone)]
 pub struct Ensemble {
@@ -24,15 +24,14 @@ impl Ensemble {
     }
 }
 
-impl Database {
 /// Update an existing ensemble or insert a new one.
-    pub fn update_ensemble(&self, mut ensemble: Ensemble) -> Result<()> {
+pub fn update_ensemble(connection: &mut SqliteConnection, mut ensemble: Ensemble) -> Result<()> {
     info!("Updating ensemble {:?}", ensemble);
-        self.defer_foreign_keys()?;
+    defer_foreign_keys(connection)?;
 
     ensemble.last_used = Some(Utc::now().timestamp());
 
-        self.connection.lock().unwrap().transaction(|connection| {
+    connection.transaction(|connection| {
         diesel::replace_into(ensembles::table)
             .values(ensemble)
             .execute(connection)
@@ -42,10 +41,10 @@ impl Database {
 }
 
 /// Get an existing ensemble.
-    pub fn get_ensemble(&self, id: &str) -> Result<Option<Ensemble>> {
+pub fn get_ensemble(connection: &mut SqliteConnection, id: &str) -> Result<Option<Ensemble>> {
     let ensemble = ensembles::table
         .filter(ensembles::id.eq(id))
-            .load::<Ensemble>(&mut *self.connection.lock().unwrap())?
+        .load::<Ensemble>(connection)?
         .into_iter()
         .next();
 
@@ -53,25 +52,23 @@ impl Database {
 }
 
 /// Delete an existing ensemble.
-    pub fn delete_ensemble(&self, id: &str) -> Result<()> {
+pub fn delete_ensemble(connection: &mut SqliteConnection, id: &str) -> Result<()> {
     info!("Deleting ensemble {}", id);
-        diesel::delete(ensembles::table.filter(ensembles::id.eq(id)))
-            .execute(&mut *self.connection.lock().unwrap())?;
+    diesel::delete(ensembles::table.filter(ensembles::id.eq(id))).execute(connection)?;
     Ok(())
 }
 
 /// Get all existing ensembles.
-    pub fn get_ensembles(&self) -> Result<Vec<Ensemble>> {
-        let ensembles = ensembles::table.load::<Ensemble>(&mut *self.connection.lock().unwrap())?;
+pub fn get_ensembles(connection: &mut SqliteConnection) -> Result<Vec<Ensemble>> {
+    let ensembles = ensembles::table.load::<Ensemble>(connection)?;
     Ok(ensembles)
 }
 
 /// Get recently used ensembles.
-    pub fn get_recent_ensembles(&self) -> Result<Vec<Ensemble>> {
+pub fn get_recent_ensembles(connection: &mut SqliteConnection) -> Result<Vec<Ensemble>> {
     let ensembles = ensembles::table
         .order(ensembles::last_used.desc())
-            .load::<Ensemble>(&mut *self.connection.lock().unwrap())?;
+        .load::<Ensemble>(connection)?;
 
     Ok(ensembles)
 }
-}

crates/database/src/instruments.rs

@@ -1,9 +1,9 @@
-use super::schema::instruments;
-use super::{Database, Result};
 use chrono::Utc;
 use diesel::prelude::*;
 use log::info;
 
+use crate::{defer_foreign_keys, schema::instruments, Result};
+
 /// An instrument or any other possible role within a recording.
 #[derive(Insertable, Queryable, PartialEq, Eq, Hash, Debug, Clone)]
 pub struct Instrument {
@@ -24,15 +24,17 @@ impl Instrument {
     }
 }
 
-impl Database {
 /// Update an existing instrument or insert a new one.
-    pub fn update_instrument(&self, mut instrument: Instrument) -> Result<()> {
+pub fn update_instrument(
+    connection: &mut SqliteConnection,
+    mut instrument: Instrument,
+) -> Result<()> {
     info!("Updating instrument {:?}", instrument);
-        self.defer_foreign_keys()?;
+    defer_foreign_keys(connection)?;
 
     instrument.last_used = Some(Utc::now().timestamp());
 
-        self.connection.lock().unwrap().transaction(|connection| {
+    connection.transaction(|connection| {
         diesel::replace_into(instruments::table)
             .values(instrument)
             .execute(connection)
@@ -42,10 +44,10 @@ impl Database {
 }
 
 /// Get an existing instrument.
-    pub fn get_instrument(&self, id: &str) -> Result<Option<Instrument>> {
+pub fn get_instrument(connection: &mut SqliteConnection, id: &str) -> Result<Option<Instrument>> {
     let instrument = instruments::table
         .filter(instruments::id.eq(id))
-            .load::<Instrument>(&mut *self.connection.lock().unwrap())?
+        .load::<Instrument>(connection)?
         .into_iter()
         .next();
 
@@ -53,28 +55,25 @@ impl Database {
 }
 
 /// Delete an existing instrument.
-    pub fn delete_instrument(&self, id: &str) -> Result<()> {
+pub fn delete_instrument(connection: &mut SqliteConnection, id: &str) -> Result<()> {
     info!("Deleting instrument {}", id);
-        diesel::delete(instruments::table.filter(instruments::id.eq(id)))
-            .execute(&mut *self.connection.lock().unwrap())?;
+    diesel::delete(instruments::table.filter(instruments::id.eq(id))).execute(connection)?;
 
     Ok(())
 }
 
 /// Get all existing instruments.
-    pub fn get_instruments(&self) -> Result<Vec<Instrument>> {
-        let instruments =
-            instruments::table.load::<Instrument>(&mut *self.connection.lock().unwrap())?;
+pub fn get_instruments(connection: &mut SqliteConnection) -> Result<Vec<Instrument>> {
+    let instruments = instruments::table.load::<Instrument>(connection)?;
 
     Ok(instruments)
 }
 
 /// Get recently used instruments.
-    pub fn get_recent_instruments(&self) -> Result<Vec<Instrument>> {
+pub fn get_recent_instruments(connection: &mut SqliteConnection) -> Result<Vec<Instrument>> {
     let instruments = instruments::table
         .order(instruments::last_used.desc())
-            .load::<Instrument>(&mut *self.connection.lock().unwrap())?;
+        .load::<Instrument>(connection)?;
 
     Ok(instruments)
 }
-}

crates/database/src/lib.rs

@@ -1,9 +1,9 @@
-use diesel_migrations::{embed_migrations, EmbeddedMigrations, MigrationHarness};
-use std::sync::{Arc, Mutex};
-
 use diesel::prelude::*;
+use diesel_migrations::{embed_migrations, EmbeddedMigrations, MigrationHarness};
 use log::info;
 
+pub use diesel::SqliteConnection;
+
 pub mod ensembles;
 pub use ensembles::*;
 
@@ -30,19 +30,8 @@ mod schema;
 // This makes the SQL migration scripts accessible from the code.
 const MIGRATIONS: EmbeddedMigrations = embed_migrations!();
 
-/// Generate a random string suitable as an item ID.
-pub fn generate_id() -> String {
-    uuid::Uuid::new_v4().simple().to_string()
-}
-
-/// Interface to a Musicus database.
-pub struct Database {
-    connection: Arc<Mutex<SqliteConnection>>,
-}
-
-impl Database {
-    /// Create a new database interface and run migrations if necessary.
-    pub fn new(file_name: &str) -> Result<Database> {
+/// Connect to a Musicus database running migrations if necessary.
+pub fn connect(file_name: &str) -> Result<SqliteConnection> {
     info!("Opening database file '{}'", file_name);
     let mut connection = SqliteConnection::establish(file_name)?;
     diesel::sql_query("PRAGMA foreign_keys = ON").execute(&mut connection)?;
@@ -50,15 +39,16 @@ impl Database {
     info!("Running migrations if necessary");
     connection.run_pending_migrations(MIGRATIONS)?;
 
-        Ok(Database {
-            connection: Arc::new(Mutex::new(connection)),
-        })
+    Ok(connection)
+}
+
+/// Generate a random string suitable as an item ID.
+pub fn generate_id() -> String {
+    uuid::Uuid::new_v4().simple().to_string()
 }
 
 /// Defer all foreign keys for the next transaction.
-    fn defer_foreign_keys(&self) -> Result<()> {
-        diesel::sql_query("PRAGMA defer_foreign_keys = ON")
-            .execute(&mut *self.connection.lock().unwrap())?;
+fn defer_foreign_keys(connection: &mut SqliteConnection) -> Result<()> {
+    diesel::sql_query("PRAGMA defer_foreign_keys = ON").execute(connection)?;
     Ok(())
 }
-}

crates/database/src/medium.rs

@@ -1,10 +1,13 @@
-use super::generate_id;
-use super::schema::{ensembles, mediums, performances, persons, recordings, tracks};
-use super::{Database, Error, Recording, Result};
 use chrono::{DateTime, TimeZone, Utc};
 use diesel::prelude::*;
 use log::info;
 
+use crate::{
+    defer_foreign_keys, generate_id, get_recording,
+    schema::{ensembles, mediums, performances, persons, recordings, tracks},
+    update_recording, Error, Recording, Result,
+};
+
 /// Representation of someting like a physical audio disc or a folder with
 /// audio files (i.e. a collection of tracks for one or more recordings).
 #[derive(PartialEq, Eq, Hash, Debug, Clone)]
@@ -103,20 +106,16 @@ struct TrackRow {
     pub last_played: Option<i64>,
 }
 
-impl Database {
 /// Update an existing medium or insert a new one.
-    pub fn update_medium(&self, medium: Medium) -> Result<()> {
+pub fn update_medium(connection: &mut SqliteConnection, medium: Medium) -> Result<()> {
     info!("Updating medium {:?}", medium);
-        self.defer_foreign_keys()?;
+    defer_foreign_keys(connection)?;
 
-        self.connection
-            .lock()
-            .unwrap()
-            .transaction::<(), Error, _>(|connection| {
+    connection.transaction::<(), Error, _>(|connection| {
         let medium_id = &medium.id;
 
         // This will also delete the tracks.
-                self.delete_medium(medium_id)?;
+        delete_medium(connection, medium_id)?;
 
         // Add the new medium.
 
@@ -135,8 +134,8 @@ impl Database {
         for (index, track) in medium.tracks.iter().enumerate() {
             // Add associated items from the server, if they don't already exist.
 
-                    if self.get_recording(&track.recording.id)?.is_none() {
-                        self.update_recording(track.recording.clone())?;
+            if get_recording(connection, &track.recording.id)?.is_none() {
+                update_recording(connection, track.recording.clone())?;
             }
 
             // Add the actual track data.
@@ -172,15 +171,15 @@ impl Database {
 }
 
 /// Get an existing medium.
-    pub fn get_medium(&self, id: &str) -> Result<Option<Medium>> {
+pub fn get_medium(connection: &mut SqliteConnection, id: &str) -> Result<Option<Medium>> {
     let row = mediums::table
         .filter(mediums::id.eq(id))
-            .load::<MediumRow>(&mut *self.connection.lock().unwrap())?
+        .load::<MediumRow>(connection)?
         .into_iter()
         .next();
 
     let medium = match row {
-            Some(row) => Some(self.get_medium_data(row)?),
+        Some(row) => Some(get_medium_data(connection, row)?),
         None => None,
     };
 
@@ -188,15 +187,18 @@ impl Database {
 }
 
 /// Get mediums that have a specific source ID.
-    pub fn get_mediums_by_source_id(&self, source_id: &str) -> Result<Vec<Medium>> {
+pub fn get_mediums_by_source_id(
+    connection: &mut SqliteConnection,
+    source_id: &str,
+) -> Result<Vec<Medium>> {
     let mut mediums: Vec<Medium> = Vec::new();
 
     let rows = mediums::table
         .filter(mediums::discid.nullable().eq(source_id))
-            .load::<MediumRow>(&mut *self.connection.lock().unwrap())?;
+        .load::<MediumRow>(connection)?;
 
     for row in rows {
-            let medium = self.get_medium_data(row)?;
+        let medium = get_medium_data(connection, row)?;
         mediums.push(medium);
     }
 
@@ -204,7 +206,10 @@ impl Database {
 }
 
 /// Get mediums on which this person is performing.
-    pub fn get_mediums_for_person(&self, person_id: &str) -> Result<Vec<Medium>> {
+pub fn get_mediums_for_person(
+    connection: &mut SqliteConnection,
+    person_id: &str,
+) -> Result<Vec<Medium>> {
     let mut mediums: Vec<Medium> = Vec::new();
 
     let rows = mediums::table
@@ -215,10 +220,10 @@ impl Database {
         .filter(persons::id.eq(person_id))
         .select(mediums::table::all_columns())
         .distinct()
-            .load::<MediumRow>(&mut *self.connection.lock().unwrap())?;
+        .load::<MediumRow>(connection)?;
 
     for row in rows {
-            let medium = self.get_medium_data(row)?;
+        let medium = get_medium_data(connection, row)?;
         mediums.push(medium);
     }
 
@@ -226,7 +231,10 @@ impl Database {
 }
 
 /// Get mediums on which this ensemble is performing.
-    pub fn get_mediums_for_ensemble(&self, ensemble_id: &str) -> Result<Vec<Medium>> {
+pub fn get_mediums_for_ensemble(
+    connection: &mut SqliteConnection,
+    ensemble_id: &str,
+) -> Result<Vec<Medium>> {
     let mut mediums: Vec<Medium> = Vec::new();
 
     let rows = mediums::table
@@ -237,10 +245,10 @@ impl Database {
         .filter(ensembles::id.eq(ensemble_id))
         .select(mediums::table::all_columns())
         .distinct()
-            .load::<MediumRow>(&mut *self.connection.lock().unwrap())?;
+        .load::<MediumRow>(connection)?;
 
     for row in rows {
-            let medium = self.get_medium_data(row)?;
+        let medium = get_medium_data(connection, row)?;
         mediums.push(medium);
     }
 
@@ -249,25 +257,24 @@ impl Database {
 
 /// Delete a medium and all of its tracks. This will fail, if the music
 /// library contains audio files referencing any of those tracks.
-    pub fn delete_medium(&self, id: &str) -> Result<()> {
+pub fn delete_medium(connection: &mut SqliteConnection, id: &str) -> Result<()> {
     info!("Deleting medium {}", id);
-        diesel::delete(mediums::table.filter(mediums::id.eq(id)))
-            .execute(&mut *self.connection.lock().unwrap())?;
+    diesel::delete(mediums::table.filter(mediums::id.eq(id))).execute(connection)?;
     Ok(())
 }
 
 /// Get all available tracks for a recording.
-    pub fn get_tracks(&self, recording_id: &str) -> Result<Vec<Track>> {
+pub fn get_tracks(connection: &mut SqliteConnection, recording_id: &str) -> Result<Vec<Track>> {
     let mut tracks: Vec<Track> = Vec::new();
 
     let rows = tracks::table
         .inner_join(recordings::table.on(recordings::id.eq(tracks::recording)))
         .filter(recordings::id.eq(recording_id))
         .select(tracks::table::all_columns())
-            .load::<TrackRow>(&mut *self.connection.lock().unwrap())?;
+        .load::<TrackRow>(connection)?;
 
     for row in rows {
-            let track = self.get_track_from_row(row)?;
+        let track = get_track_from_row(connection, row)?;
         tracks.push(track);
     }
 
@@ -275,27 +282,27 @@ impl Database {
 }
 
 /// Get a random track from the database.
-    pub fn random_track(&self) -> Result<Track> {
+pub fn random_track(connection: &mut SqliteConnection) -> Result<Track> {
     let row = diesel::sql_query("SELECT * FROM tracks ORDER BY RANDOM() LIMIT 1")
-            .load::<TrackRow>(&mut *self.connection.lock().unwrap())?
+        .load::<TrackRow>(connection)?
         .into_iter()
         .next()
         .ok_or(Error::Other("Failed to generate random track"))?;
 
-        self.get_track_from_row(row)
+    get_track_from_row(connection, row)
 }
 
 /// Retrieve all available information on a medium from related tables.
-    fn get_medium_data(&self, row: MediumRow) -> Result<Medium> {
+fn get_medium_data(connection: &mut SqliteConnection, row: MediumRow) -> Result<Medium> {
     let track_rows = tracks::table
         .filter(tracks::medium.eq(&row.id))
         .order_by(tracks::index)
-            .load::<TrackRow>(&mut *self.connection.lock().unwrap())?;
+        .load::<TrackRow>(connection)?;
 
     let mut tracks = Vec::new();
 
     for track_row in track_rows {
-            let track = self.get_track_from_row(track_row)?;
+        let track = get_track_from_row(connection, track_row)?;
         tracks.push(track);
     }
 
@@ -312,11 +319,10 @@ impl Database {
 }
 
 /// Convert a track row from the database to an actual track.
-    fn get_track_from_row(&self, row: TrackRow) -> Result<Track> {
+fn get_track_from_row(connection: &mut SqliteConnection, row: TrackRow) -> Result<Track> {
     let recording_id = row.recording;
 
-        let recording = self
-            .get_recording(&recording_id)?
+    let recording = get_recording(connection, &recording_id)?
         .ok_or(Error::MissingItem("recording", recording_id))?;
 
     let mut part_indices = Vec::new();
@@ -343,4 +349,3 @@ impl Database {
 
     Ok(track)
 }
-}

crates/database/src/persons.rs

@@ -1,9 +1,9 @@
-use super::schema::persons;
-use super::{Database, Result};
 use chrono::Utc;
 use diesel::prelude::*;
 use log::info;
 
+use crate::{defer_foreign_keys, schema::persons, Result};
+
 /// A person that is a composer, an interpret or both.
 #[derive(Insertable, Queryable, PartialEq, Eq, Hash, Debug, Clone)]
 pub struct Person {
@@ -35,16 +35,14 @@ impl Person {
         format!("{}, {}", self.last_name, self.first_name)
     }
 }
-
-impl Database {
 /// Update an existing person or insert a new one.
-    pub fn update_person(&self, mut person: Person) -> Result<()> {
+pub fn update_person(connection: &mut SqliteConnection, mut person: Person) -> Result<()> {
     info!("Updating person {:?}", person);
-        self.defer_foreign_keys()?;
+    defer_foreign_keys(connection)?;
 
     person.last_used = Some(Utc::now().timestamp());
 
-        self.connection.lock().unwrap().transaction(|connection| {
+    connection.transaction(|connection| {
         diesel::replace_into(persons::table)
             .values(person)
             .execute(connection)
@@ -54,10 +52,10 @@ impl Database {
 }
 
 /// Get an existing person.
-    pub fn get_person(&self, id: &str) -> Result<Option<Person>> {
+pub fn get_person(connection: &mut SqliteConnection, id: &str) -> Result<Option<Person>> {
     let person = persons::table
         .filter(persons::id.eq(id))
-            .load::<Person>(&mut *self.connection.lock().unwrap())?
+        .load::<Person>(connection)?
         .into_iter()
         .next();
 
@@ -65,26 +63,24 @@ impl Database {
 }
 
 /// Delete an existing person.
-    pub fn delete_person(&self, id: &str) -> Result<()> {
+pub fn delete_person(connection: &mut SqliteConnection, id: &str) -> Result<()> {
     info!("Deleting person {}", id);
-        diesel::delete(persons::table.filter(persons::id.eq(id)))
-            .execute(&mut *self.connection.lock().unwrap())?;
+    diesel::delete(persons::table.filter(persons::id.eq(id))).execute(connection)?;
     Ok(())
 }
 
 /// Get all existing persons.
-    pub fn get_persons(&self) -> Result<Vec<Person>> {
-        let persons = persons::table.load::<Person>(&mut *self.connection.lock().unwrap())?;
+pub fn get_persons(connection: &mut SqliteConnection) -> Result<Vec<Person>> {
+    let persons = persons::table.load::<Person>(connection)?;
 
     Ok(persons)
 }
 
 /// Get recently used persons.
-    pub fn get_recent_persons(&self) -> Result<Vec<Person>> {
+pub fn get_recent_persons(connection: &mut SqliteConnection) -> Result<Vec<Person>> {
     let persons = persons::table
         .order(persons::last_used.desc())
-            .load::<Person>(&mut *self.connection.lock().unwrap())?;
+        .load::<Person>(connection)?;
 
     Ok(persons)
 }
-}

crates/database/src/recordings.rs

@@ -1,10 +1,14 @@
-use super::generate_id;
-use super::schema::{ensembles, performances, persons, recordings};
-use super::{Database, Ensemble, Error, Instrument, Person, Result, Work};
 use chrono::{DateTime, TimeZone, Utc};
 use diesel::prelude::*;
 use log::info;
 
+use crate::{
+    defer_foreign_keys, generate_id, get_ensemble, get_instrument, get_person, get_work,
+    schema::{ensembles, performances, persons, recordings},
+    update_ensemble, update_instrument, update_person, update_work, Ensemble, Error, Instrument,
+    Person, Result, Work,
+};
+
 /// A specific recording of a work.
 #[derive(PartialEq, Eq, Hash, Debug, Clone)]
 pub struct Recording {
@@ -125,42 +129,39 @@ struct PerformanceRow {
     pub role: Option<String>,
 }
 
-impl Database {
 /// Update an existing recording or insert a new one.
 // TODO: Think about whether to also insert the other items.
-    pub fn update_recording(&self, recording: Recording) -> Result<()> {
+pub fn update_recording(connection: &mut SqliteConnection, recording: Recording) -> Result<()> {
     info!("Updating recording {:?}", recording);
-        self.defer_foreign_keys()?;
-        self.connection
-            .lock()
-            .unwrap()
-            .transaction::<(), Error, _>(|connection| {
+    defer_foreign_keys(connection)?;
+
+    connection.transaction::<(), Error, _>(|connection| {
         let recording_id = &recording.id;
-                self.delete_recording(recording_id)?;
+        delete_recording(connection, recording_id)?;
 
         // Add associated items from the server, if they don't already exist.
 
-                if self.get_work(&recording.work.id)?.is_none() {
-                    self.update_work(recording.work.clone())?;
+        if get_work(connection, &recording.work.id)?.is_none() {
+            update_work(connection, recording.work.clone())?;
         }
 
         for performance in &recording.performances {
             match &performance.performer {
                 PersonOrEnsemble::Person(person) => {
-                            if self.get_person(&person.id)?.is_none() {
-                                self.update_person(person.clone())?;
+                    if get_person(connection, &person.id)?.is_none() {
+                        update_person(connection, person.clone())?;
                     }
                 }
                 PersonOrEnsemble::Ensemble(ensemble) => {
-                            if self.get_ensemble(&ensemble.id)?.is_none() {
-                                self.update_ensemble(ensemble.clone())?;
+                    if get_ensemble(connection, &ensemble.id)?.is_none() {
+                        update_ensemble(connection, ensemble.clone())?;
                     }
                 }
             }
 
             if let Some(role) = &performance.role {
-                        if self.get_instrument(&role.id)?.is_none() {
-                            self.update_instrument(role.clone())?;
+                if get_instrument(connection, &role.id)?.is_none() {
+                    update_instrument(connection, role.clone())?;
                 }
             }
         }
@@ -198,10 +199,10 @@ impl Database {
 }
 
 /// Check whether the database contains a recording.
-    pub fn recording_exists(&self, id: &str) -> Result<bool> {
+pub fn recording_exists(connection: &mut SqliteConnection, id: &str) -> Result<bool> {
     let exists = recordings::table
         .filter(recordings::id.eq(id))
-            .load::<RecordingRow>(&mut *self.connection.lock().unwrap())?
+        .load::<RecordingRow>(connection)?
         .first()
         .is_some();
 
@@ -209,15 +210,15 @@ impl Database {
 }
 
 /// Get an existing recording.
-    pub fn get_recording(&self, id: &str) -> Result<Option<Recording>> {
+pub fn get_recording(connection: &mut SqliteConnection, id: &str) -> Result<Option<Recording>> {
     let row = recordings::table
         .filter(recordings::id.eq(id))
-            .load::<RecordingRow>(&mut *self.connection.lock().unwrap())?
+        .load::<RecordingRow>(connection)?
         .into_iter()
         .next();
 
     let recording = match row {
-            Some(row) => Some(self.get_recording_data(row)?),
+        Some(row) => Some(get_recording_data(connection, row)?),
         None => None,
     };
 
@@ -225,43 +226,40 @@ impl Database {
 }
 
 /// Get a random recording from the database.
-    pub fn random_recording(&self) -> Result<Recording> {
+pub fn random_recording(connection: &mut SqliteConnection) -> Result<Recording> {
     let row = diesel::sql_query("SELECT * FROM recordings ORDER BY RANDOM() LIMIT 1")
-            .load::<RecordingRow>(&mut *self.connection.lock().unwrap())?
+        .load::<RecordingRow>(connection)?
         .into_iter()
         .next()
         .ok_or(Error::Other("Failed to find random recording."))?;
 
-        self.get_recording_data(row)
+    get_recording_data(connection, row)
 }
 
 /// Retrieve all available information on a recording from related tables.
-    fn get_recording_data(&self, row: RecordingRow) -> Result<Recording> {
+fn get_recording_data(connection: &mut SqliteConnection, row: RecordingRow) -> Result<Recording> {
     let mut performance_descriptions: Vec<Performance> = Vec::new();
 
     let performance_rows = performances::table
         .filter(performances::recording.eq(&row.id))
-            .load::<PerformanceRow>(&mut *self.connection.lock().unwrap())?;
+        .load::<PerformanceRow>(connection)?;
 
     for row in performance_rows {
         performance_descriptions.push(Performance {
             performer: if let Some(id) = row.person {
                 PersonOrEnsemble::Person(
-                        self.get_person(&id)?
-                            .ok_or(Error::MissingItem("person", id))?,
+                    get_person(connection, &id)?.ok_or(Error::MissingItem("person", id))?,
                 )
             } else if let Some(id) = row.ensemble {
                 PersonOrEnsemble::Ensemble(
-                        self.get_ensemble(&id)?
-                            .ok_or(Error::MissingItem("ensemble", id))?,
+                    get_ensemble(connection, &id)?.ok_or(Error::MissingItem("ensemble", id))?,
                 )
             } else {
                 return Err(Error::Other("Performance without performer"));
             },
             role: match row.role {
                 Some(id) => Some(
-                        self.get_instrument(&id)?
-                            .ok_or(Error::MissingItem("instrument", id))?,
+                    get_instrument(connection, &id)?.ok_or(Error::MissingItem("instrument", id))?,
                 ),
                 None => None,
             },
@@ -269,9 +267,7 @@ impl Database {
     }
 
     let work_id = row.work;
-        let work = self
-            .get_work(&work_id)?
-            .ok_or(Error::MissingItem("work", work_id))?;
+    let work = get_work(connection, &work_id)?.ok_or(Error::MissingItem("work", work_id))?;
 
     let recording_description = Recording {
         id: row.id,
@@ -286,7 +282,10 @@ impl Database {
 }
 
 /// Get all available information on all recordings where a person is performing.
-    pub fn get_recordings_for_person(&self, person_id: &str) -> Result<Vec<Recording>> {
+pub fn get_recordings_for_person(
+    connection: &mut SqliteConnection,
+    person_id: &str,
+) -> Result<Vec<Recording>> {
     let mut recordings: Vec<Recording> = Vec::new();
 
     let rows = recordings::table
@@ -294,17 +293,20 @@ impl Database {
         .inner_join(persons::table.on(persons::id.nullable().eq(performances::person)))
         .filter(persons::id.eq(person_id))
         .select(recordings::table::all_columns())
-            .load::<RecordingRow>(&mut *self.connection.lock().unwrap())?;
+        .load::<RecordingRow>(connection)?;
 
     for row in rows {
-            recordings.push(self.get_recording_data(row)?);
+        recordings.push(get_recording_data(connection, row)?);
     }
 
     Ok(recordings)
 }
 
 /// Get all available information on all recordings where an ensemble is performing.
-    pub fn get_recordings_for_ensemble(&self, ensemble_id: &str) -> Result<Vec<Recording>> {
+pub fn get_recordings_for_ensemble(
+    connection: &mut SqliteConnection,
+    ensemble_id: &str,
+) -> Result<Vec<Recording>> {
     let mut recordings: Vec<Recording> = Vec::new();
 
     let rows = recordings::table
@@ -312,25 +314,28 @@ impl Database {
         .inner_join(ensembles::table.on(ensembles::id.nullable().eq(performances::ensemble)))
         .filter(ensembles::id.eq(ensemble_id))
         .select(recordings::table::all_columns())
-            .load::<RecordingRow>(&mut *self.connection.lock().unwrap())?;
+        .load::<RecordingRow>(connection)?;
 
     for row in rows {
-            recordings.push(self.get_recording_data(row)?);
+        recordings.push(get_recording_data(connection, row)?);
     }
 
     Ok(recordings)
 }
 
 /// Get allavailable information on all recordings of a work.
-    pub fn get_recordings_for_work(&self, work_id: &str) -> Result<Vec<Recording>> {
+pub fn get_recordings_for_work(
+    connection: &mut SqliteConnection,
+    work_id: &str,
+) -> Result<Vec<Recording>> {
     let mut recordings: Vec<Recording> = Vec::new();
 
     let rows = recordings::table
         .filter(recordings::work.eq(work_id))
-            .load::<RecordingRow>(&mut *self.connection.lock().unwrap())?;
+        .load::<RecordingRow>(connection)?;
 
     for row in rows {
-            recordings.push(self.get_recording_data(row)?);
+        recordings.push(get_recording_data(connection, row)?);
     }
 
     Ok(recordings)
@@ -338,10 +343,8 @@ impl Database {
 
 /// Delete an existing recording. This will fail if there are still references to this
 /// recording from other tables that are not directly part of the recording data.
-    pub fn delete_recording(&self, id: &str) -> Result<()> {
+pub fn delete_recording(connection: &mut SqliteConnection, id: &str) -> Result<()> {
     info!("Deleting recording {}", id);
-        diesel::delete(recordings::table.filter(recordings::id.eq(id)))
-            .execute(&mut *self.connection.lock().unwrap())?;
+    diesel::delete(recordings::table.filter(recordings::id.eq(id))).execute(connection)?;
     Ok(())
 }
-}

crates/database/src/works.rs

@@ -1,11 +1,13 @@
-use super::generate_id;
-use super::schema::{instrumentations, work_parts, works};
-use super::{Database, Error, Instrument, Person, Result};
 use chrono::{DateTime, TimeZone, Utc};
-use diesel::prelude::*;
-use diesel::{Insertable, Queryable};
+use diesel::{prelude::*, Insertable, Queryable};
 use log::info;
 
+use crate::{
+    defer_foreign_keys, generate_id, get_instrument, get_person,
+    schema::{instrumentations, work_parts, works},
+    update_instrument, update_person, Error, Instrument, Person, Result,
+};
+
 /// Table row data for a work.
 #[derive(Insertable, Queryable, Debug, Clone)]
 #[table_name = "works"]
@@ -105,29 +107,25 @@ impl Work {
     }
 }
 
-impl Database {
 /// Update an existing work or insert a new one.
 // TODO: Think about also inserting related items.
-    pub fn update_work(&self, work: Work) -> Result<()> {
+pub fn update_work(connection: &mut SqliteConnection, work: Work) -> Result<()> {
     info!("Updating work {:?}", work);
-        self.defer_foreign_keys()?;
+    defer_foreign_keys(connection)?;
 
-        self.connection
-            .lock()
-            .unwrap()
-            .transaction::<(), Error, _>(|connection| {
+    connection.transaction::<(), Error, _>(|connection| {
         let work_id = &work.id;
-                self.delete_work(work_id)?;
+        delete_work(connection, work_id)?;
 
         // Add associated items from the server, if they don't already exist.
 
-                if self.get_person(&work.composer.id)?.is_none() {
-                    self.update_person(work.composer.clone())?;
+        if get_person(connection, &work.composer.id)?.is_none() {
+            update_person(connection, work.composer.clone())?;
         }
 
         for instrument in &work.instruments {
-                    if self.get_instrument(&instrument.id)?.is_none() {
-                        self.update_instrument(instrument.clone())?;
+            if get_instrument(connection, &instrument.id)?.is_none() {
+                update_instrument(connection, instrument.clone())?;
             }
         }
 
@@ -136,7 +134,7 @@ impl Database {
         let row: WorkRow = work.clone().into();
         diesel::insert_into(works::table)
             .values(row)
-                    .execute(&mut *self.connection.lock().unwrap())?;
+            .execute(connection)?;
 
         let Work {
             instruments, parts, ..
@@ -174,15 +172,15 @@ impl Database {
 }
 
 /// Get an existing work.
-    pub fn get_work(&self, id: &str) -> Result<Option<Work>> {
+pub fn get_work(connection: &mut SqliteConnection, id: &str) -> Result<Option<Work>> {
     let row = works::table
         .filter(works::id.eq(id))
-            .load::<WorkRow>(&mut *self.connection.lock().unwrap())?
+        .load::<WorkRow>(connection)?
         .first()
         .cloned();
 
     let work = match row {
-            Some(row) => Some(self.get_work_data(row)?),
+        Some(row) => Some(get_work_data(connection, row)?),
         None => None,
     };
 
@@ -190,26 +188,24 @@ impl Database {
 }
 
 /// Retrieve all available information on a work from related tables.
-    fn get_work_data(&self, row: WorkRow) -> Result<Work> {
+fn get_work_data(connection: &mut SqliteConnection, row: WorkRow) -> Result<Work> {
     let mut instruments: Vec<Instrument> = Vec::new();
 
     let instrumentations = instrumentations::table
         .filter(instrumentations::work.eq(&row.id))
-            .load::<InstrumentationRow>(&mut *self.connection.lock().unwrap())?;
+        .load::<InstrumentationRow>(connection)?;
 
     for instrumentation in instrumentations {
         let id = instrumentation.instrument;
-            instruments.push(
-                self.get_instrument(&id)?
-                    .ok_or(Error::MissingItem("instrument", id))?,
-            );
+        instruments
+            .push(get_instrument(connection, &id)?.ok_or(Error::MissingItem("instrument", id))?);
     }
 
     let mut parts: Vec<WorkPart> = Vec::new();
 
     let part_rows = work_parts::table
         .filter(work_parts::work.eq(&row.id))
-            .load::<WorkPartRow>(&mut *self.connection.lock().unwrap())?;
+        .load::<WorkPartRow>(connection)?;
 
     for part_row in part_rows {
         parts.push(WorkPart {
@@ -218,9 +214,8 @@ impl Database {
     }
 
     let person_id = row.composer;
-        let person = self
-            .get_person(&person_id)?
-            .ok_or(Error::MissingItem("person", person_id))?;
+    let person =
+        get_person(connection, &person_id)?.ok_or(Error::MissingItem("person", person_id))?;
 
     Ok(Work {
         id: row.id,
@@ -235,25 +230,23 @@ impl Database {
 
 /// Delete an existing work. This will fail if there are still other tables that relate to
 /// this work except for the things that are part of the information on the work it
-    pub fn delete_work(&self, id: &str) -> Result<()> {
+pub fn delete_work(connection: &mut SqliteConnection, id: &str) -> Result<()> {
     info!("Deleting work {}", id);
-        diesel::delete(works::table.filter(works::id.eq(id)))
-            .execute(&mut *self.connection.lock().unwrap())?;
+    diesel::delete(works::table.filter(works::id.eq(id))).execute(connection)?;
     Ok(())
 }
 
 /// Get all existing works by a composer and related information from other tables.
-    pub fn get_works(&self, composer_id: &str) -> Result<Vec<Work>> {
+pub fn get_works(connection: &mut SqliteConnection, composer_id: &str) -> Result<Vec<Work>> {
     let mut works: Vec<Work> = Vec::new();
 
     let rows = works::table
         .filter(works::composer.eq(composer_id))
-            .load::<WorkRow>(&mut *self.connection.lock().unwrap())?;
+        .load::<WorkRow>(connection)?;
 
     for row in rows {
-            works.push(self.get_work_data(row)?);
+        works.push(get_work_data(connection, row)?);
     }
 
     Ok(works)
 }
-}

crates/musicus/src/editors/ensemble.rs

@@ -3,7 +3,7 @@ use crate::widgets::{Editor, Section, Widget};
 use anyhow::Result;
 use gettextrs::gettext;
 use gtk::{builders::ListBoxBuilder, glib::clone, prelude::*};
-use musicus_backend::db::{generate_id, Ensemble};
+use musicus_backend::db::{generate_id, Ensemble, self};
 use std::rc::Rc;
 
 /// A dialog for creating or editing a ensemble.
@@ -88,7 +88,7 @@ impl EnsembleEditor {
 
         let ensemble = Ensemble::new(self.id.clone(), name.to_string());
 
-        self.handle.backend.db().update_ensemble(ensemble.clone())?;
+        db::update_ensemble(&mut self.handle.backend.db().lock().unwrap(), ensemble.clone())?;
         self.handle.backend.library_changed();
 
         Ok(ensemble)

crates/musicus/src/editors/instrument.rs

@@ -3,7 +3,7 @@ use crate::widgets::{Editor, Section, Widget};
 use anyhow::Result;
 use gettextrs::gettext;
 use gtk::{builders::ListBoxBuilder, glib::clone, prelude::*};
-use musicus_backend::db::{generate_id, Instrument};
+use musicus_backend::db::{self, generate_id, Instrument};
 use std::rc::Rc;
 
 /// A dialog for creating or editing a instrument.
@@ -88,10 +88,11 @@ impl InstrumentEditor {
 
         let instrument = Instrument::new(self.id.clone(), name.to_string());
 
-        self.handle
-            .backend
-            .db()
-            .update_instrument(instrument.clone())?;
+        db::update_instrument(
+            &mut self.handle.backend.db().lock().unwrap(),
+            instrument.clone(),
+        )?;
+
         self.handle.backend.library_changed();
 
         Ok(instrument)

crates/musicus/src/editors/person.rs

@@ -4,7 +4,7 @@ use anyhow::Result;
 use gettextrs::gettext;
 use glib::clone;
 use gtk::{builders::ListBoxBuilder, prelude::*};
-use musicus_backend::db::{generate_id, Person};
+use musicus_backend::db::{generate_id, Person, self};
 use std::rc::Rc;
 
 /// A dialog for creating or editing a person.
@@ -110,7 +110,11 @@ impl PersonEditor {
             last_name.to_string(),
         );
 
-        self.handle.backend.db().update_person(person.clone())?;
+        db::update_person(
+            &mut self.handle.backend.db().lock().unwrap(),
+            person.clone(),
+        )?;
+
         self.handle.backend.library_changed();
 
         Ok(person)

crates/musicus/src/editors/recording.rs

@@ -8,7 +8,7 @@ use anyhow::Result;
 use gettextrs::gettext;
 use glib::clone;
 use gtk_macros::get_widget;
-use musicus_backend::db::{generate_id, Performance, Recording, Work};
+use musicus_backend::db::{self, generate_id, Performance, Recording, Work};
 use std::cell::RefCell;
 use std::rc::Rc;
 
@@ -188,10 +188,11 @@ impl RecordingEditor {
             self.performances.borrow().clone(),
         );
 
-        self.handle
-            .backend
-            .db()
-            .update_recording(recording.clone())?;
+        db::update_recording(
+            &mut self.handle.backend.db().lock().unwrap(),
+            recording.clone(),
+        )?;
+
         self.handle.backend.library_changed();
 
         Ok(recording)

crates/musicus/src/editors/work.rs

@@ -8,7 +8,7 @@ use anyhow::Result;
 use gettextrs::gettext;
 use glib::clone;
 use gtk_macros::get_widget;
-use musicus_backend::db::{generate_id, Instrument, Person, Work, WorkPart};
+use musicus_backend::db::{self, generate_id, Instrument, Person, Work, WorkPart};
 use std::cell::RefCell;
 use std::rc::Rc;
 
@@ -261,7 +261,7 @@ impl WorkEditor {
             self.parts.borrow().clone(),
         );
 
-        self.handle.backend.db().update_work(work.clone())?;
+        db::update_work(&mut self.handle.backend.db().lock().unwrap(), work.clone())?;
         self.handle.backend.library_changed();
 
         Ok(work)

crates/musicus/src/import/import_screen.rs

@@ -7,7 +7,7 @@ use adw::builders::ActionRowBuilder;
 use adw::prelude::*;
 use glib::clone;
 use gtk_macros::get_widget;
-use musicus_backend::db::Medium;
+use musicus_backend::db::{self, Medium};
 use musicus_backend::import::ImportSession;
 use std::rc::Rc;
 use std::sync::Arc;
@@ -29,7 +29,10 @@ impl ImportScreen {
 
         let this = self;
         spawn!(@clone this, async move {
-            let mediums = this.handle.backend.db().get_mediums_by_source_id(this.session.source_id());
+            let mediums = db::get_mediums_by_source_id(
+                &mut this.handle.backend.db().lock().unwrap(),
+                this.session.source_id()
+            );
 
             match mediums {
                 Ok(mediums) => {
@@ -110,7 +113,7 @@ impl Screen<Arc<ImportSession>, ()> for ImportScreen {
         get_widget!(builder, adw::ActionRow, error_row);
         get_widget!(builder, gtk::ListBox, matching_list);
         get_widget!(builder, gtk::Button, select_button);
-        get_widget!(builder, gtk::Button, add_button);
+        get_widget!(builder, gtk::Button, add_medium_button);
 
         let this = Rc::new(Self {
             handle,
@@ -139,7 +142,7 @@ impl Screen<Arc<ImportSession>, ()> for ImportScreen {
             });
         }));
 
-        add_button.connect_clicked(clone!(@weak this =>  move |_| {
+        add_medium_button.connect_clicked(clone!(@weak this =>  move |_| {
             spawn!(@clone this, async move {
                 if let Some(medium) = push!(this.handle, MediumEditor, (Arc::clone(&this.session), None)).await {
                     this.select_medium(medium);
@@ -151,7 +154,7 @@ impl Screen<Arc<ImportSession>, ()> for ImportScreen {
 
         this.load_matches();
 
-        // Copy the tracks in the background, if neccessary.
+        // Copy the tracks in the background, if necessary.
         this.session.copy();
 
         this

crates/musicus/src/import/medium_preview.rs

@@ -8,7 +8,7 @@ use glib::clone;
 use gtk::builders::{FrameBuilder, ListBoxBuilder};
 use gtk::prelude::*;
 use gtk_macros::get_widget;
-use musicus_backend::db::Medium;
+use musicus_backend::db::{self, Medium};
 use musicus_backend::import::{ImportSession, State};
 use std::cell::RefCell;
 use std::path::PathBuf;
@@ -226,7 +226,7 @@ impl MediumPreview {
         );
 
         let directory = PathBuf::from(&directory_name);
-        std::fs::create_dir(&music_library_path.join(&directory))?;
+        std::fs::create_dir(music_library_path.join(&directory))?;
 
         // Copy the tracks to the music library.
 
@@ -243,7 +243,7 @@ impl MediumPreview {
             track.path = track_path.to_str().unwrap().to_owned();
 
             // Copy the corresponding audio file to the music library.
-            std::fs::copy(&import_track.path, &music_library_path.join(&track_path))?;
+            std::fs::copy(&import_track.path, music_library_path.join(&track_path))?;
 
             tracks.push(track);
         }
@@ -257,7 +257,7 @@ impl MediumPreview {
             tracks,
         );
 
-        self.handle.backend.db().update_medium(medium)?;
+        db::update_medium(&mut self.handle.backend.db().lock().unwrap(), medium)?;
         self.handle.backend.library_changed();
 
         Ok(())

crates/musicus/src/screens/ensemble.rs

@@ -7,7 +7,7 @@ use adw::builders::ActionRowBuilder;
 use adw::prelude::*;
 use gettextrs::gettext;
 use glib::clone;
-use musicus_backend::db::{Ensemble, Medium, Recording};
+use musicus_backend::db::{self, Ensemble, Medium, Recording};
 use std::cell::RefCell;
 use std::rc::Rc;
 
@@ -60,7 +60,7 @@ impl Screen<Ensemble, ()> for EnsembleScreen {
             &gettext("Delete ensemble"),
             clone!(@weak this =>  move || {
                 spawn!(@clone this, async move {
-                    this.handle.backend.db().delete_ensemble(&this.ensemble.id).unwrap();
+                    db::delete_ensemble(&mut this.handle.backend.db().lock().unwrap(), &this.ensemble.id).unwrap();
                     this.handle.backend.library_changed();
                 });
             }),
@@ -131,18 +131,16 @@ impl Screen<Ensemble, ()> for EnsembleScreen {
 
         // Load the content.
 
-        let recordings = this
-            .handle
-            .backend
-            .db()
-            .get_recordings_for_ensemble(&this.ensemble.id)
+        let recordings = db::get_recordings_for_ensemble(
+            &mut this.handle.backend.db().lock().unwrap(),
+            &this.ensemble.id,
+        )
         .unwrap();
 
-        let mediums = this
-            .handle
-            .backend
-            .db()
-            .get_mediums_for_ensemble(&this.ensemble.id)
+        let mediums = db::get_mediums_for_ensemble(
+            &mut this.handle.backend.db().lock().unwrap(),
+            &this.ensemble.id,
+        )
         .unwrap();
 
         if !recordings.is_empty() {

crates/musicus/src/screens/main.rs

@@ -9,7 +9,7 @@ use adw::prelude::*;
 use gettextrs::gettext;
 use glib::clone;
 use gtk_macros::get_widget;
-use musicus_backend::db::PersonOrEnsemble;
+use musicus_backend::db::{self, PersonOrEnsemble};
 use std::cell::RefCell;
 use std::rc::Rc;
 
@@ -142,8 +142,9 @@ impl Screen<(), ()> for MainScreen {
         );
 
         play_button.connect_clicked(clone!(@weak this => move |_| {
-            if let Ok(recording) = this.handle.backend.db().random_recording() {
-                this.handle.backend.pl().add_items(this.handle.backend.db().get_tracks(&recording.id).unwrap()).unwrap();
+            let recording = db::random_recording(&mut this.handle.backend.db().lock().unwrap());
+            if let Ok(recording) = recording {
+                this.handle.backend.pl().add_items(db::get_tracks(&mut this.handle.backend.db().lock().unwrap(), &recording.id).unwrap()).unwrap();
             }
         }));
 
@@ -164,8 +165,8 @@ impl Screen<(), ()> for MainScreen {
 
                 let mut poes = Vec::new();
 
-                let persons = this.handle.backend.db().get_persons().unwrap();
-                let ensembles = this.handle.backend.db().get_ensembles().unwrap();
+                let persons = db::get_persons(&mut this.handle.backend.db().lock().unwrap(), ).unwrap();
+                let ensembles = db::get_ensembles(&mut this.handle.backend.db().lock().unwrap(), ).unwrap();
 
                 for person in persons {
                     poes.push(PersonOrEnsemble::Person(person));

crates/musicus/src/screens/person.rs

@@ -7,7 +7,7 @@ use adw::builders::ActionRowBuilder;
 use adw::prelude::*;
 use gettextrs::gettext;
 use glib::clone;
-use musicus_backend::db::{Medium, Person, Recording, Work};
+use musicus_backend::db::{self, Medium, Person, Recording, Work};
 use std::cell::RefCell;
 use std::rc::Rc;
 
@@ -65,7 +65,7 @@ impl Screen<Person, ()> for PersonScreen {
             &gettext("Delete person"),
             clone!(@weak this =>  move || {
                 spawn!(@clone this, async move {
-                    this.handle.backend.db().delete_person(&this.person.id).unwrap();
+                    db::delete_person(&mut this.handle.backend.db().lock().unwrap(), &this.person.id).unwrap();
                     this.handle.backend.library_changed();
                 });
             }),
@@ -165,20 +165,22 @@ impl Screen<Person, ()> for PersonScreen {
 
         // Load the content.
 
-        let works = this.handle.backend.db().get_works(&this.person.id).unwrap();
-
-        let recordings = this
-            .handle
-            .backend
-            .db()
-            .get_recordings_for_person(&this.person.id)
+        let works = db::get_works(
+            &mut this.handle.backend.db().lock().unwrap(),
+            &this.person.id,
+        )
         .unwrap();
 
-        let mediums = this
-            .handle
-            .backend
-            .db()
-            .get_mediums_for_person(&this.person.id)
+        let recordings = db::get_recordings_for_person(
+            &mut this.handle.backend.db().lock().unwrap(),
+            &this.person.id,
+        )
+        .unwrap();
+
+        let mediums = db::get_mediums_for_person(
+            &mut this.handle.backend.db().lock().unwrap(),
+            &this.person.id,
+        )
         .unwrap();
 
         if !works.is_empty() {

crates/musicus/src/screens/recording.rs

@@ -6,7 +6,7 @@ use adw::builders::ActionRowBuilder;
 use adw::prelude::*;
 use gettextrs::gettext;
 use glib::clone;
-use musicus_backend::db::{Recording, Track};
+use musicus_backend::db::{self, Recording, Track};
 use std::cell::RefCell;
 use std::rc::Rc;
 
@@ -64,7 +64,7 @@ impl Screen<Recording, ()> for RecordingScreen {
             &gettext("Delete recording"),
             clone!(@weak this =>  move || {
                 spawn!(@clone this, async move {
-                    this.handle.backend.db().delete_recording(&this.recording.id).unwrap();
+                    db::delete_recording(&mut this.handle.backend.db().lock().unwrap(), &this.recording.id).unwrap();
                     this.handle.backend.library_changed();
                 });
             }),
@@ -94,11 +94,10 @@ impl Screen<Recording, ()> for RecordingScreen {
 
         // Load the content.
 
-        let tracks = this
-            .handle
-            .backend
-            .db()
-            .get_tracks(&this.recording.id)
+        let tracks = db::get_tracks(
+            &mut this.handle.backend.db().lock().unwrap(),
+            &this.recording.id,
+        )
         .unwrap();
 
         this.show_tracks(tracks);

crates/musicus/src/screens/work.rs

@@ -7,7 +7,7 @@ use adw::builders::ActionRowBuilder;
 use adw::prelude::*;
 use gettextrs::gettext;
 use glib::clone;
-use musicus_backend::db::{Recording, Work};
+use musicus_backend::db::{self, Recording, Work};
 use std::cell::RefCell;
 use std::rc::Rc;
 
@@ -56,7 +56,7 @@ impl Screen<Work, ()> for WorkScreen {
             &gettext("Delete work"),
             clone!(@weak this =>  move || {
                 spawn!(@clone this, async move {
-                    this.handle.backend.db().delete_work(&this.work.id).unwrap();
+                    db::delete_work(&mut this.handle.backend.db().lock().unwrap(), &this.work.id).unwrap();
                     this.handle.backend.library_changed();
                 });
             }),
@@ -98,11 +98,10 @@ impl Screen<Work, ()> for WorkScreen {
 
         // Load the content.
 
-        let recordings = this
-            .handle
-            .backend
-            .db()
-            .get_recordings_for_work(&this.work.id)
+        let recordings = db::get_recordings_for_work(
+            &mut this.handle.backend.db().lock().unwrap(),
+            &this.work.id,
+        )
         .unwrap();
 
         if !recordings.is_empty() {

crates/musicus/src/selectors/ensemble.rs

@@ -7,7 +7,7 @@ use adw::prelude::*;
 use gettextrs::gettext;
 use glib::clone;
 use log::warn;
-use musicus_backend::db::Ensemble;
+use musicus_backend::db::{Ensemble, self};
 use std::rc::Rc;
 
 /// A screen for selecting a ensemble.
@@ -50,7 +50,7 @@ impl Screen<(), Ensemble> for EnsembleSelector {
                 let ensemble = ensemble.to_owned();
 
                 row.connect_activated(clone!(@weak this =>  move |_| {
-                    if let Err(err) = this.handle.backend.db().update_ensemble(ensemble.clone()) {
+                    if let Err(err) = db::update_ensemble(&mut this.handle.backend.db().lock().unwrap(), ensemble.clone()) {
                         warn!("Failed to update access time. {err}");
                     }
 
@@ -64,7 +64,7 @@ impl Screen<(), Ensemble> for EnsembleSelector {
             .set_filter(|search, ensemble| ensemble.name.to_lowercase().contains(search));
 
         this.selector
-            .set_items(this.handle.backend.db().get_recent_ensembles().unwrap());
+            .set_items(db::get_recent_ensembles(&mut this.handle.backend.db().lock().unwrap(), ).unwrap());
 
         this
     }

crates/musicus/src/selectors/instrument.rs

@@ -7,7 +7,7 @@ use adw::prelude::*;
 use gettextrs::gettext;
 use glib::clone;
 use log::warn;
-use musicus_backend::db::Instrument;
+use musicus_backend::db::{Instrument, self};
 use std::rc::Rc;
 
 /// A screen for selecting a instrument.
@@ -50,7 +50,7 @@ impl Screen<(), Instrument> for InstrumentSelector {
                 let instrument = instrument.to_owned();
 
                 row.connect_activated(clone!(@weak this =>  move |_| {
-                    if let Err(err) = this.handle.backend.db().update_instrument(instrument.clone()) {
+                    if let Err(err) = db::update_instrument(&mut this.handle.backend.db().lock().unwrap(), instrument.clone()) {
                         warn!("Failed to update access time. {err}");
                     }
 
@@ -64,7 +64,7 @@ impl Screen<(), Instrument> for InstrumentSelector {
             .set_filter(|search, instrument| instrument.name.to_lowercase().contains(search));
 
         this.selector
-            .set_items(this.handle.backend.db().get_recent_instruments().unwrap());
+            .set_items(db::get_recent_instruments(&mut this.handle.backend.db().lock().unwrap(), ).unwrap());
 
         this
     }

crates/musicus/src/selectors/medium.rs

@@ -6,7 +6,7 @@ use adw::prelude::*;
 use gettextrs::gettext;
 use glib::clone;
 use log::warn;
-use musicus_backend::db::{Medium, PersonOrEnsemble};
+use musicus_backend::db::{self, Medium, PersonOrEnsemble};
 use std::rc::Rc;
 
 /// A screen for selecting a medium.
@@ -56,8 +56,10 @@ impl Screen<(), Medium> for MediumSelector {
 
         let mut poes = Vec::new();
 
-        let persons = this.handle.backend.db().get_recent_persons().unwrap();
-        let ensembles = this.handle.backend.db().get_recent_ensembles().unwrap();
+        let persons =
+            db::get_recent_persons(&mut this.handle.backend.db().lock().unwrap()).unwrap();
+        let ensembles =
+            db::get_recent_ensembles(&mut this.handle.backend.db().lock().unwrap()).unwrap();
 
         for person in persons {
             poes.push(PersonOrEnsemble::Person(person));
@@ -111,7 +113,7 @@ impl Screen<PersonOrEnsemble, Medium> for MediumSelectorMediumScreen {
 
                 let medium = medium.to_owned();
                 row.connect_activated(clone!(@weak this =>  move |_| {
-                    if let Err(err) = this.handle.backend.db().update_medium(medium.clone()) {
+                    if let Err(err) = db::update_medium(&mut this.handle.backend.db().lock().unwrap(), medium.clone()) {
                         warn!("Failed to update access time. {err}");
                     }
 
@@ -128,19 +130,19 @@ impl Screen<PersonOrEnsemble, Medium> for MediumSelectorMediumScreen {
         match this.poe.clone() {
             PersonOrEnsemble::Person(person) => {
                 this.selector.set_items(
-                    this.handle
-                        .backend
-                        .db()
-                        .get_mediums_for_person(&person.id)
+                    db::get_mediums_for_person(
+                        &mut this.handle.backend.db().lock().unwrap(),
+                        &person.id,
+                    )
                     .unwrap(),
                 );
             }
             PersonOrEnsemble::Ensemble(ensemble) => {
                 this.selector.set_items(
-                    this.handle
-                        .backend
-                        .db()
-                        .get_mediums_for_ensemble(&ensemble.id)
+                    db::get_mediums_for_ensemble(
+                        &mut this.handle.backend.db().lock().unwrap(),
+                        &ensemble.id,
+                    )
                     .unwrap(),
                 );
             }

crates/musicus/src/selectors/person.rs

@@ -7,7 +7,7 @@ use adw::prelude::*;
 use gettextrs::gettext;
 use glib::clone;
 use log::warn;
-use musicus_backend::db::Person;
+use musicus_backend::db::{Person, self};
 use std::rc::Rc;
 
 /// A screen for selecting a person.
@@ -50,7 +50,7 @@ impl Screen<(), Person> for PersonSelector {
                 let person = person.to_owned();
 
                 row.connect_activated(clone!(@weak this =>  move |_| {
-                    if let Err(err) = this.handle.backend.db().update_person(person.clone()) {
+                    if let Err(err) = db::update_person(&mut this.handle.backend.db().lock().unwrap(), person.clone()) {
                         warn!("Failed to update access time. {err}");
                     }
 
@@ -64,7 +64,7 @@ impl Screen<(), Person> for PersonSelector {
             .set_filter(|search, person| person.name_fl().to_lowercase().contains(search));
 
         this.selector
-            .set_items(this.handle.backend.db().get_recent_persons().unwrap());
+            .set_items(db::get_recent_persons(&mut this.handle.backend.db().lock().unwrap(), ).unwrap());
 
         this
     }

crates/musicus/src/selectors/recording.rs

@@ -7,7 +7,7 @@ use adw::prelude::*;
 use gettextrs::gettext;
 use glib::clone;
 use log::warn;
-use musicus_backend::db::{Person, Recording, Work};
+use musicus_backend::db::{self, Person, Recording, Work};
 use std::rc::Rc;
 
 /// A screen for selecting a recording.
@@ -81,8 +81,9 @@ impl Screen<(), Recording> for RecordingSelector {
         this.selector
             .set_filter(|search, person| person.name_fl().to_lowercase().contains(search));
 
-        this.selector
-            .set_items(this.handle.backend.db().get_recent_persons().unwrap());
+        this.selector.set_items(
+            db::get_recent_persons(&mut this.handle.backend.db().lock().unwrap()).unwrap(),
+        );
 
         this
     }
@@ -144,8 +145,13 @@ impl Screen<Person, Work> for RecordingSelectorWorkScreen {
         this.selector
             .set_filter(|search, work| work.title.to_lowercase().contains(search));
 
-        this.selector
-            .set_items(this.handle.backend.db().get_works(&this.person.id).unwrap());
+        this.selector.set_items(
+            db::get_works(
+                &mut this.handle.backend.db().lock().unwrap(),
+                &this.person.id,
+            )
+            .unwrap(),
+        );
 
         this
     }
@@ -198,7 +204,7 @@ impl Screen<Work, Recording> for RecordingSelectorRecordingScreen {
 
                 let recording = recording.to_owned();
                 row.connect_activated(clone!(@weak this =>  move |_| {
-                    if let Err(err) = this.handle.backend.db().update_recording(recording.clone()) {
+                    if let Err(err) = db::update_recording(&mut this.handle.backend.db().lock().unwrap(), recording.clone()) {
                         warn!("Failed to update access time. {err}");
                     }
 
@@ -213,10 +219,10 @@ impl Screen<Work, Recording> for RecordingSelectorRecordingScreen {
         });
 
         this.selector.set_items(
-            this.handle
-                .backend
-                .db()
-                .get_recordings_for_work(&this.work.id)
+            db::get_recordings_for_work(
+                &mut this.handle.backend.db().lock().unwrap(),
+                &this.work.id,
+            )
             .unwrap(),
         );
 

crates/musicus/src/selectors/work.rs

@@ -7,7 +7,7 @@ use adw::prelude::*;
 use gettextrs::gettext;
 use glib::clone;
 use log::warn;
-use musicus_backend::db::{Person, Work};
+use musicus_backend::db::{Person, Work, self};
 use std::rc::Rc;
 
 /// A screen for selecting a work.
@@ -72,7 +72,7 @@ impl Screen<(), Work> for WorkSelector {
             .set_filter(|search, person| person.name_fl().to_lowercase().contains(search));
 
         this.selector
-            .set_items(this.handle.backend.db().get_recent_persons().unwrap());
+            .set_items(db::get_recent_persons(&mut this.handle.backend.db().lock().unwrap()).unwrap());
 
         this
     }
@@ -125,7 +125,7 @@ impl Screen<Person, Work> for WorkSelectorWorkScreen {
 
                 let work = work.to_owned();
                 row.connect_activated(clone!(@weak this =>  move |_| {
-                    if let Err(err) = this.handle.backend.db().update_work(work.clone()) {
+                    if let Err(err) = db::update_work(&mut this.handle.backend.db().lock().unwrap(), work.clone()) {
                         warn!("Failed to update access time. {err}");
                     }
 
@@ -139,7 +139,7 @@ impl Screen<Person, Work> for WorkSelectorWorkScreen {
             .set_filter(|search, work| work.title.to_lowercase().contains(search));
 
         this.selector
-            .set_items(this.handle.backend.db().get_works(&this.person.id).unwrap());
+            .set_items(db::get_works(&mut this.handle.backend.db().lock().unwrap(), &this.person.id).unwrap());
 
         this
     }