Separate out sessions. Starts addressing issue #10

We were creating a session in the "Add from database" dialog, and then
creating another session (with the first still active) in _repaint().

Separated out sessions; also don't call _save_playlist from _repaint
as it doesn't really have any connection.

app/musicmuster.py

@@ -74,7 +74,7 @@ class Window(QMainWindow, Ui_MainWindow):
             with Session() as session:
                 for fname in dlg.selectedFiles():
                     track = add_path_to_db(session, fname)
-                    self.visible_playlist()._add_to_playlist(track)
+                    self.visible_playlist().add_to_playlist(session, track)
 
     def set_main_window_size(self):
 
@@ -623,7 +623,6 @@ class Window(QMainWindow, Ui_MainWindow):
 class DbDialog(QDialog):
     def __init__(self, parent=None):
         super().__init__(parent)
-        self.session = Session()
         self.ui = Ui_Dialog()
         self.ui.setupUi(self)
         self.ui.searchString.textEdited.connect(self.chars_typed)
@@ -633,20 +632,22 @@ class DbDialog(QDialog):
         self.ui.btnClose.clicked.connect(self.close)
         self.ui.matchList.itemSelectionChanged.connect(self.selection_changed)
 
-        record = Settings.get_int(self.session, "dbdialog_width")
+        with Session() as session:
-        width = record.f_int or 800
+            record = Settings.get_int(session, "dbdialog_width")
-        record = Settings.get_int(self.session, "dbdialog_height")
+            width = record.f_int or 800
-        height = record.f_int or 600
+            record = Settings.get_int(session, "dbdialog_height")
-        self.resize(width, height)
+            height = record.f_int or 600
+            self.resize(width, height)
 
     def __del__(self):
-        record = Settings.get_int(self.session, "dbdialog_height")
+        with Session() as session:
-        if record.f_int != self.height():
+            record = Settings.get_int(session, "dbdialog_height")
-            record.update(self.session, {'f_int': self.height()})
+            if record.f_int != self.height():
+                record.update(session, {'f_int': self.height()})
 
-        record = Settings.get_int(self.session, "dbdialog_width")
+            record = Settings.get_int(session, "dbdialog_width")
-        if record.f_int != self.width():
+            if record.f_int != self.width():
-            record.update(self.session, {'f_int': self.width()})
+                record.update(session, {'f_int': self.width()})
 
     def add_selected(self):
         if not self.ui.matchList.selectedItems():
@@ -661,18 +662,19 @@ class DbDialog(QDialog):
         self.close()
 
     def chars_typed(self, s):
-        if len(s) >= 3:
+        if len(s) > 0:
-            matches = Tracks.search_titles(self.session, s)
+            with Session() as session:
-            self.ui.matchList.clear()
+                matches = Tracks.search_titles(session, s)
-            if matches:
+                self.ui.matchList.clear()
-                for track in matches:
+                if matches:
-                    t = QListWidgetItem()
+                    for track in matches:
-                    t.setText(
+                        t = QListWidgetItem()
-                        f"{track.title} - {track.artist} "
+                        t.setText(
-                        f"[{helpers.ms_to_mmss(track.duration)}]"
+                            f"{track.title} - {track.artist} "
-                    )
+                            f"[{helpers.ms_to_mmss(track.duration)}]"
-                    t.setData(Qt.UserRole, track.id)
+                        )
-                    self.ui.matchList.addItem(t)
+                        t.setData(Qt.UserRole, track.id)
+                        self.ui.matchList.addItem(t)
 
     def double_click(self, entry):
         track_id = entry.data(Qt.UserRole)
@@ -681,8 +683,9 @@ class DbDialog(QDialog):
         self.select_searchtext()
 
     def add_track(self, track_id):
-        track = Tracks.track_from_id(self.session, track_id)
+        with Session() as session:
-        self.parent().visible_playlist()._add_to_playlist(track)
+            track = Tracks.track_from_id(session, track_id)
+            self.parent().visible_playlist().add_to_playlist(session, track)
         # Select search text to make it easier for next search
         self.select_searchtext()
 
@@ -696,7 +699,8 @@ class DbDialog(QDialog):
 
         item = self.ui.matchList.currentItem()
         track_id = item.data(Qt.UserRole)
-        self.ui.dbPath.setText(Tracks.get_path(self.session, track_id))
+        with Session() as session:
+            self.ui.dbPath.setText(Tracks.get_path(session, track_id))
 
 
 class SelectPlaylistDialog(QDialog):

app/playlists.py

@@ -141,6 +141,8 @@ class Playlist(QTableWidget):
             f"Moved row(s) {rows} to become row {drop_row}"
         )
 
+        with Session() as session:
+            self._save_playlist(session)
         self._repaint()
 
     def eventFilter(self, source, event):
@@ -165,7 +167,7 @@ class Playlist(QTableWidget):
 
     # ########## Externally called functions ##########
 
-    def add_note(self, note, repaint=True):
+    def add_note(self,  session, note, repaint=True):
         """
         Add note to playlist
 
@@ -211,9 +213,23 @@ class Playlist(QTableWidget):
         self.scrollToItem(titleitem, QAbstractItemView.PositionAtCenter)
 
         if repaint:
+            self._save_playlist(session)
             self._repaint(clear_selection=False)
 
-    def add_track(self, track, repaint=True):
+    def add_to_playlist(self, session, data, repaint=True):
+        """
+        Add data to playlist. Data may be either a Tracks object or a
+        Notes object.
+        """
+
+        DEBUG(f"add_to_playlist(session={session}, data={data})")
+
+        if isinstance(data, Tracks):
+            self.add_track(session, data, repaint=repaint)
+        elif isinstance(data, Notes):
+            self.add_note(session, data, repaint=repaint)
+
+    def add_track(self, session, track, repaint=True):
         """
         Add track to playlist
 
@@ -250,6 +266,7 @@ class Playlist(QTableWidget):
         self.scrollToItem(titleitem, QAbstractItemView.PositionAtCenter)
 
         if repaint:
+            self._save_playlist(session)
             self._repaint(clear_selection=False)
 
     def clear_current(self):
@@ -353,12 +370,13 @@ class Playlist(QTableWidget):
 
         # Now add data in row order
         for item in sorted(data, key=lambda x: x[0]):
-            self._add_to_playlist(item[1], repaint=False)
+            self.add_to_playlist(session, item[1], repaint=False)
 
         # Scroll to top
         scroll_to = self.item(0, self.COL_INDEX)
         self.scrollToItem(scroll_to, QAbstractItemView.PositionAtTop)
 
+        self._save_playlist(session)
         self._repaint()
 
     def repaint(self):
@@ -442,19 +460,6 @@ class Playlist(QTableWidget):
 
     # ########## Internally called functions ##########
 
-    def _add_to_playlist(self, data, repaint=True):
-        """
-        Add data to playlist. Data may be either a Tracks object or a
-        Notes object.
-        """
-
-        DEBUG(f"_add_to_playlist(data={data})")
-
-        if isinstance(data, Tracks):
-            self.add_track(data, repaint=repaint)
-        elif isinstance(data, Notes):
-            self.add_note(data, repaint=repaint)
-
     def _calculate_next_start_time(self, session, row, start):
         "Return this row's end time given its start time"
 
@@ -490,7 +495,7 @@ class Playlist(QTableWidget):
             DEBUG("playlist._delete_row(): Can't delete next track")
             return
 
-        else:
+        with Session() as session:
             title = self.item(row, self.COL_TITLE).text()
 
             msg = QMessageBox(self)
@@ -500,14 +505,14 @@ class Playlist(QTableWidget):
             msg.setDefaultButton(QMessageBox.Cancel)
             msg.setWindowTitle("Delete row")
             if msg.exec() == QMessageBox.Yes:
-                with Session() as session:
+                id = self._get_row_id(row)
-                    id = self._get_row_id(row)
+                if row in self._meta_get_notes():
-                    if row in self._meta_get_notes():
+                    Notes.delete_note(session, id)
-                        Notes.delete_note(session, id)
+                else:
-                    else:
+                    PlaylistTracks.remove_track(session, self.db.id, row)
-                        PlaylistTracks.remove_track(session, self.db.id, row)
+                self.removeRow(row)
-                    self.removeRow(row)
 
+        self._save_playlist(session)
         self._repaint()
 
     def _drop_on(self, event):
@@ -716,20 +721,17 @@ class Playlist(QTableWidget):
             self._repaint(save_playlist=False)
             self.master_process.set_next_track(track_id)
 
-    def _repaint(self, clear_selection=True, save_playlist=True):
+    def _repaint(self, clear_selection=True):
-        "Set row colours, fonts, etc, and save playlist"
+        "Set row colours, fonts, etc"
 
         DEBUG(
             f"playlist[{self.db.id}:{self.db.name}]."
-            f"_repaint(clear_selection={clear_selection}, "
+            f"_repaint(clear_selection={clear_selection}"
-            f"save_playlist={save_playlist})"
         )
 
         with Session() as session:
             if clear_selection:
                 self.clearSelection()
-            if save_playlist:
-                self._save_playlist(session)
 
             current = self._meta_get_current()
             next = self._meta_get_next()