Add command to backup the database

openslides/main.py

@@ -89,6 +89,9 @@ def process_options(argv=None, manage_runserver=False):
     parser.add_option(
         "--syncdb", action="store_true",
         help="Update/create database before starting the server.")
+    parser.add_option(
+        "--backupdb", action="store", metavar="BACKUP_PATH",
+        help="Make a backup copy of the database to BACKUP_PATH")
     parser.add_option(
         "--reset-admin", action="store_true",
         help="Make sure the user 'admin' exists and uses 'admin' as password.")
@@ -190,6 +193,9 @@ def _main(opts, database_path=None):
     elif opts.reset_admin:
         create_or_reset_admin_user()
 
+    if opts.backupdb:
+        backup_database(opts.backupdb)
+
     if opts.no_run:
         return
 
@@ -320,6 +326,11 @@ def create_or_reset_admin_user():
     admin.save()
 
 
+def backup_database(dest_path):
+    argv = ["", "backupdb", "--destination={0}".format(dest_path)]
+    execute_from_command_line(argv)
+
+
 def start_browser(url):
     browser = webbrowser.get()
 

openslides/utils/management/commands/backupdb.py

@@ -0,0 +1,53 @@
+import shutil
+from optparse import make_option
+
+import django.conf
+import django.db
+import django.db.transaction
+from django.core.management.base import NoArgsCommand, CommandError
+
+
+class Command(NoArgsCommand):
+    help = "Backup the openslides database"
+    option_list = NoArgsCommand.option_list + (
+        make_option(
+            "--destination", action="store",
+            help="path to the backup database (will be overwritten)"),
+    )
+
+    def handle_noargs(self, *args, **kw):
+        db_settings = django.conf.settings.DATABASES
+        default = db_settings.get(django.db.DEFAULT_DB_ALIAS)
+        if not default:
+            raise CommandError("Default databases is not configured")
+
+        if default.get("ENGINE") != "django.db.backends.sqlite3":
+            raise CommandError(
+                "Only sqlite3 databases can currently be backuped")
+
+        src_path = default.get("NAME")
+        if not src_path:
+            raise CommandError("No path specified for default database")
+
+        dest_path = kw.get("destination")
+        if not dest_path:
+            raise CommandError("--destination must be specified")
+
+        self.do_backup(src_path, dest_path)
+
+    @django.db.transaction.commit_manually
+    def do_backup(self, src_path, dest_path):
+        # perform a simple file-copy backup of the database
+        # first we need a shared lock on the database, issuing a select()
+        # will do this for us
+        cursor = django.db.connection.cursor()
+        cursor.execute("SELECT count(*) from sqlite_master")
+
+        # now copy the file
+        try:
+            shutil.copy(src_path, dest_path)
+        except IOError as e:
+            raise CommandError("{0}\nDatabase backup failed!".format(e))
+
+        # and release the lock again
+        django.db.transaction.commit()