db: Add an ArtistTable and Artist tag

Also create an index on artist name in the sqlite table for faster
lookups.

Signed-off-by: Anna Schumaker <Anna@NoWheyCreamery.com>

db/__init__.py

@@ -10,3 +10,11 @@ Connection.row_factory = sqlite3.Row
 commit = Connection.commit
 execute = Connection.execute
 executemany = Connection.executemany
+
+from . import artist
+
+def reset():
+    mods = [ artist ]
+
+    for mod in mods: mod.Table.drop()
+    for mod in mods: mod.Table.do_create()

db/artist.py

@@ -0,0 +1,49 @@
+# Copyright 2021 (c) Anna Schumaker.
+#
+# Table: artists
+# +----------+------+------+
+# | artistid | name | sort |
+# +----------+------+------+
+#
+# Index: artist_index
+# +------------------+
+# | name -> artistid |
+# +------------------+
+from . import execute
+from . import objects
+
+class Artist(objects.Tag):
+    def do_get_column(self, column):
+        return execute(f"SELECT {column} FROM artists "
+                        "WHERE artistid=?", [ self.rowid ])
+
+
+class ArtistTable(objects.Table):
+    def __init__(self):
+        objects.Table.__init__(self, "artists", Artist)
+
+    def do_create(self):
+        execute("CREATE TABLE IF NOT EXISTS artists "
+                    "(artistid INTEGER PRIMARY KEY, "
+                    " name TEXT UNIQUE, "
+                    " sort TEXT)")
+        execute("CREATE INDEX IF NOT EXISTS artist_index "
+                "ON artists(name)")
+
+    def do_insert(self, name, sort):
+        return execute("INSERT INTO artists (name, sort) "
+                       "VALUES (?, ?)", (name, sort.casefold()))
+
+    def do_delete(self, artist):
+        return execute("DELETE FROM artists WHERE artistid=?", [ int(artist) ])
+
+    def do_get(self, rowid):
+        return execute("SELECT artistid FROM artists "
+                       "WHERE artistid=?", [ rowid ])
+
+    def do_lookup(self, name, sort=None):
+        return execute("SELECT artistid FROM artists "
+                       "WHERE name=?", [ name ])
+
+
+Table = ArtistTable()

db/test_artist.py

@@ -0,0 +1,51 @@
+# Copyright 2021 (c) Anna Schumaker.
+import db
+import sqlite3
+import unittest
+from gi.repository import GObject
+
+
+class TestArtistTable(unittest.TestCase):
+    def on_row_inserted(self, table, row):
+        self.row_inserted = row
+
+    def on_row_deleted(self, table, row):
+        self.row_deleted = row
+
+    def setUp(self):
+        db.reset()
+
+    def test_artist_table_init(self):
+        self.assertIsInstance(db.artist.Table, db.artist.ArtistTable)
+        db.execute("SELECT artistid,name,sort FROM artists")
+
+    def test_artist_table_insert(self):
+        db.artist.Table.connect("row-inserted", self.on_row_inserted)
+
+        artist = db.artist.Table.insert("Test Artist", "Test Sort")
+        self.assertIsInstance(artist, db.artist.Artist)
+        self.assertIsInstance(artist, db.objects.Tag)
+        self.assertEqual(self.row_inserted, artist)
+
+        self.assertEqual(artist.name, "Test Artist")
+        self.assertEqual(artist.sort, "test sort")
+
+        with self.assertRaises(sqlite3.IntegrityError):
+            db.artist.Table.insert("Test Artist", "Test Sort")
+
+    def test_artist_table_delete(self):
+        artist = db.artist.Table.find("Test Artist", "Test Sort")
+        db.artist.Table.connect("row-deleted", self.on_row_deleted)
+
+        db.artist.Table.delete(artist)
+        self.assertIsNone(db.artist.Table.lookup("Test Artist"))
+
+    def test_artist_table_get(self):
+        artist = db.artist.Table.insert("Test Artist", "Test Sort")
+        self.assertEqual(db.artist.Table.get(1), artist)
+        self.assertIsNone(db.artist.Table.get(2))
+
+    def test_artist_table_lookup(self):
+        artist = db.artist.Table.insert("Test Artist", "Test Sort")
+        self.assertEqual(db.artist.Table.lookup("Test Artist"), artist)
+        self.assertIsNone(db.artist.Table.lookup("none"))