Refactor databases.mainDB -> databases

core/databases.py

@@ -0,0 +1,65 @@
+# coding=utf-8
+
+from core import logger, nzbToMediaDB
+from core.nzbToMediaUtil import backup_versioned_file
+
+MIN_DB_VERSION = 1  # oldest db version we support migrating from
+MAX_DB_VERSION = 2
+
+
+def backup_database(version):
+    logger.info("Backing up database before upgrade")
+    if not backup_versioned_file(nzbToMediaDB.db_filename(), version):
+        logger.log_error_and_exit("Database backup failed, abort upgrading database")
+    else:
+        logger.info("Proceeding with upgrade")
+
+
+# ======================
+# = Main DB Migrations =
+# ======================
+# Add new migrations at the bottom of the list; subclass the previous migration.
+
+class InitialSchema(nzbToMediaDB.SchemaUpgrade):
+    def test(self):
+        no_update = False
+        if self.has_table("db_version"):
+            cur_db_version = self.check_db_version()
+            no_update = not cur_db_version < MAX_DB_VERSION
+        return no_update
+
+    def execute(self):
+        if not self.has_table("downloads") and not self.has_table("db_version"):
+            queries = [
+                "CREATE TABLE db_version (db_version INTEGER);",
+                "CREATE TABLE downloads (input_directory TEXT, input_name TEXT, input_hash TEXT, input_id TEXT, client_agent TEXT, status INTEGER, last_update NUMERIC, CONSTRAINT pk_downloadID PRIMARY KEY (input_directory, input_name));",
+                "INSERT INTO db_version (db_version) VALUES (2);"
+            ]
+            for query in queries:
+                self.connection.action(query)
+
+        else:
+            cur_db_version = self.check_db_version()
+
+            if cur_db_version < MIN_DB_VERSION:
+                logger.log_error_and_exit(u"Your database version ({current}) is too old to migrate "
+                                          u"from what this version of nzbToMedia supports ({min})."
+                                          u"\nPlease remove nzbtomedia.db file to begin fresh.".format
+                                          (current=cur_db_version, min=MIN_DB_VERSION))
+
+            if cur_db_version > MAX_DB_VERSION:
+                logger.log_error_and_exit(u"Your database version ({current}) has been incremented "
+                                          u"past what this version of nzbToMedia supports ({max})."
+                                          u"\nIf you have used other forks of nzbToMedia, your database "
+                                          u"may be unusable due to their modifications.".format
+                                          (current=cur_db_version, max=MAX_DB_VERSION))
+            if cur_db_version < MAX_DB_VERSION:  # We need to upgrade.
+                queries = [
+                    "CREATE TABLE downloads2 (input_directory TEXT, input_name TEXT, input_hash TEXT, input_id TEXT, client_agent TEXT, status INTEGER, last_update NUMERIC, CONSTRAINT pk_downloadID PRIMARY KEY (input_directory, input_name));",
+                    "INSERT INTO downloads2 SELECT * FROM downloads;",
+                    "DROP TABLE IF EXISTS downloads;",
+                    "ALTER TABLE downloads2 RENAME TO downloads;",
+                    "INSERT INTO db_version (db_version) VALUES (2);"
+                ]
+                for query in queries:
+                    self.connection.action(query)