Split DB_INIT into pragmas and full init, like Etiquette.

ycdl/ycdldb.py

@@ -7,6 +7,7 @@ from . import exceptions
 from . import helpers
 from . import ytapi
 
+from voussoirkit import pathclass
 from voussoirkit import sqlhelpers
 
 
@@ -21,10 +22,18 @@ logging.getLogger('requests.packages.urllib3.connectionpool').setLevel(logging.W
 logging.getLogger('requests.packages.urllib3.util.retry').setLevel(logging.WARNING)
 
 DATABASE_VERSION = 4
-DB_INIT = '''
+DB_VERSION_PRAGMA = '''
+PRAGMA user_version = {user_version};
+'''
+DB_PRAGMAS = '''
 PRAGMA count_changes = OFF;
 PRAGMA cache_size = 10000;
-PRAGMA user_version = {user_version};
+'''
+DB_INIT = f'''
+BEGIN;
+----------------------------------------------------------------------------------------------------
+{DB_PRAGMAS}
+{DB_VERSION_PRAGMA}
 CREATE TABLE IF NOT EXISTS channels(
     id TEXT,
     name TEXT,
@@ -49,6 +58,8 @@ CREATE INDEX IF NOT EXISTS index_video_author_download on videos(author_id, down
 CREATE INDEX IF NOT EXISTS index_video_id on videos(id);
 CREATE INDEX IF NOT EXISTS index_video_published on videos(published);
 CREATE INDEX IF NOT EXISTS index_video_download on videos(download);
+----------------------------------------------------------------------------------------------------
+COMMIT;
 '''.format(user_version=DATABASE_VERSION)
 
 SQL_CHANNEL_COLUMNS = [
@@ -84,29 +95,53 @@ def assert_is_abspath(path):
 
 
 class YCDLDB:
-    def __init__(self, youtube, database_filename=None, youtube_dl_function=None):
+    def __init__(
+            self,
+            youtube,
+            database_filename=None,
+            youtube_dl_function=None,
+            skip_version_check=False,
+        ):
         self.youtube = youtube
         if database_filename is None:
             database_filename = DEFAULT_DBNAME
 
-        existing_database = os.path.exists(database_filename)
+        self.database_filepath = pathclass.Path(database_filename)
+        existing_database = self.database_filepath.exists
         self.sql = sqlite3.connect(database_filename)
         self.cur = self.sql.cursor()
 
         if existing_database:
-            self.cur.execute('PRAGMA user_version')
-            existing_version = self.cur.fetchone()[0]
-            if existing_version != DATABASE_VERSION:
-                raise exceptions.DatabaseOutOfDate(current=existing_version, new=DATABASE_VERSION)
+            if not skip_version_check:
+                self._check_version()
+            self._load_pragmas()
+        else:
+            self._first_time_setup()
 
         if youtube_dl_function:
             self.youtube_dl_function = youtube_dl_function
         else:
             self.youtube_dl_function = YOUTUBE_DL_COMMAND
 
-        statements = DB_INIT.split(';')
-        for statement in statements:
-            self.cur.execute(statement)
+    def _check_version(self):
+        '''
+        Compare database's user_version against DATABASE_VERSION,
+        raising exceptions.DatabaseOutOfDate if not correct.
+        '''
+        existing = self.sql.execute('PRAGMA user_version').fetchone()[0]
+        if existing != DATABASE_VERSION:
+            raise exceptions.DatabaseOutOfDate(
+                existing=existing,
+                new=DATABASE_VERSION,
+                filepath=self.database_filepath,
+            )
+
+    def _first_time_setup(self):
+        self.sql.executescript(DB_INIT)
+        self.sql.commit()
+
+    def _load_pragmas(self):
+        self.sql.executescript(DB_PRAGMAS)
         self.sql.commit()
 
     def add_channel(