Properly close database connections when they're not in use

Daemon startup, background scans
Ref #253

supysonic/daemon/server.py

@@ -1,7 +1,7 @@
 # This file is part of Supysonic.
 # Supysonic is a Python implementation of the Subsonic server API.
 #
-# Copyright (C) 2019-2022 Alban 'spl0k' Féron
+# Copyright (C) 2019-2023 Alban 'spl0k' Féron
 #
 # Distributed under terms of the GNU AGPLv3 license.
 
@@ -12,7 +12,7 @@ from multiprocessing.connection import Listener, Client
 from threading import Thread, Event
 
 from .client import DaemonCommand
-from ..db import Folder
+from ..db import Folder, open_connection, close_connection
 from ..jukebox import Jukebox
 from ..scanner import Scanner
 from ..utils import get_secret_key
@@ -59,6 +59,8 @@ class Daemon:
         if self.__config.DAEMON["jukebox_command"]:
             self.__jukebox = Jukebox(self.__config.DAEMON["jukebox_command"])
 
+        close_connection()
+
         Thread(target=self.__listen).start()
         while not self.__stopped.is_set():
             time.sleep(1)
@@ -72,9 +74,11 @@ class Daemon:
 
     def start_scan(self, folders=[], force=False):
         if not folders:
+            open_connection()
             folders = [
                 t[0] for t in Folder.select(Folder.name).where(Folder.root).tuples()
             ]
+            close_connection()
 
         if self.__scanner is not None and self.__scanner.is_alive():
             for f in folders:

supysonic/db.py

@@ -681,8 +681,8 @@ def release_database():
     db.initialize(None)
 
 
-def open_connection():
+def open_connection(reuse=False):
-    db.connect()
+    return db.connect(reuse)
 
 
 def close_connection():

supysonic/scanner.py

@@ -1,7 +1,7 @@
 # This file is part of Supysonic.
 # Supysonic is a Python implementation of the Subsonic server API.
 #
-# Copyright (C) 2013-2022 Alban 'spl0k' Féron
+# Copyright (C) 2013-2023 Alban 'spl0k' Féron
 #
 # Distributed under terms of the GNU AGPLv3 license.
 
@@ -16,7 +16,7 @@ from queue import Queue, Empty as QueueEmpty
 from threading import Thread, Event
 
 from .covers import find_cover_in_folder, CoverFile
-from .db import Folder, Artist, Album, Track
+from .db import Folder, Artist, Album, Track, open_connection, close_connection
 
 
 logger = logging.getLogger(__name__)
@@ -95,6 +95,8 @@ class Scanner(Thread):
         self.__queue.put(folder_name)
 
     def run(self):
+        opened = open_connection(True)
+
         while not self.__stopped.is_set():
             try:
                 folder_name = self.__queue.get(False)
@@ -113,6 +115,9 @@ class Scanner(Thread):
         if self.__on_done is not None:
             self.__on_done()
 
+        if opened:
+            close_connection()
+
     def stop(self):
         self.__stopped.set()
 

supysonic/web.py

@@ -51,7 +51,11 @@ def create_application(config=None):
     # Initialize database
     init_database(app.config["BASE"]["database_uri"])
     if not app.testing:
-        app.before_request(open_connection)
+
+        def open_conn():  # Just to discard the return value
+            open_connection()
+
+        app.before_request(open_conn)
         app.teardown_request(lambda exc: close_connection())
 
     # Insert unknown mimetypes