scanner: Add a RemoveLibraryScheduler task

For breaking the tracklist into chunks, and then following up their
removal with a library table removal

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

scanner/task.py

@@ -113,3 +113,20 @@ class RemoveLibraryTask(Task):
     def run_task(self):
         db.library.Table.delete(self.library)
         db.commit()
+
+
+class RemoveLibrarySchedulerTask(Task):
+    def __init__(self, library):
+        Task.__init__(self)
+        self.library = library
+
+    def track_chunks(self):
+        tracks = self.library.tracks()
+        while len(tracks) > 0:
+            res = tracks[:50]
+            tracks = tracks[50:]
+            yield res
+
+    def run_task(self):
+        return [ RemoveTask(tracks) for tracks in self.track_chunks() ] + \
+               [ RemoveLibraryTask(self.library) ]

scanner/test_task.py

@@ -194,3 +194,32 @@ class TestScannerRemoveLibraryTask(unittest.TestCase):
 
         self.assertIsNone(rlt.run_task())
         self.assertIsNone(db.library.Table.lookup(test_tracks))
+
+
+class TestScannerRemoveLibrarySchedulerTask(unittest.TestCase):
+    def setUp(self):
+        db.reset()
+
+    def test_scanner_check_scheduler_task(self):
+        lib = db.library.Table.find(test_tracks)
+        for i in range(75):
+            db.make_fake_track(i, i, f"Test Track {i}",f"/a/b/c/{i}.ogg", lib.path)
+
+        rlst = task.RemoveLibrarySchedulerTask(lib)
+        self.assertIsInstance(rlst, task.Task)
+        self.assertEqual(rlst.library, lib)
+
+        tasks = rlst.run_task()
+        self.assertEqual(len(tasks), 3)
+        self.assertIsInstance(tasks[0], task.RemoveTask)
+        self.assertIsInstance(tasks[1], task.RemoveTask)
+        self.assertIsInstance(tasks[2], task.RemoveLibraryTask)
+        self.assertEqual(len(tasks[0].tracks), 50)
+        self.assertEqual(len(tasks[1].tracks), 25)
+        self.assertEqual(tasks[2].library, lib)
+
+        for t in tasks: t.run_task()
+
+        for i in range(1, 76):
+            self.assertIsNone(db.track.Table.get(i))
+        self.assertIsNone(db.library.Table.lookup(test_tracks))