Alter the type for the contents column of stored_file

This was previously set as a Text() which is limited at 65535 [1].
Add a wrapper to use the mysql long text column when applicable (adapted
from Heat [3]).

[1] https://mariadb.com/kb/en/mariadb/data-types/
[2] http://docs.sqlalchemy.org/en/latest/core/type_basics.html#vendor-specific-types
[3] https://github.com/openstack/heat/blob/master/heat/db/sqlalchemy/types.py#L24

Change-Id: I826686e33ba2716108c30ca3dac7ea66f079e1c0
Closes-Bug: https://bugzilla.redhat.com/show_bug.cgi?id=1222718
Co-Authored-By: jason.dobies@redhat.com

tuskar/db/sqlalchemy/migrate_repo/versions/005_fix_stored_file_contents.py

@@ -0,0 +1,43 @@
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+from oslo_db.sqlalchemy import utils
+from sqlalchemy import MetaData
+
+from tuskar.db.sqlalchemy.types import LongText
+from tuskar.openstack.common.gettextutils import _  # noqa
+from tuskar.openstack.common import log as logging
+
+
+LOG = logging.getLogger(__name__)
+
+ENGINE = 'InnoDB'
+CHARSET = 'utf8'
+
+
+def upgrade(migrate_engine):
+    meta = MetaData()
+    meta.bind = migrate_engine
+    stored_file = utils.get_table(migrate_engine, 'stored_file')
+
+    try:
+        LOG.info(repr(stored_file))
+        col = stored_file._columns.get('contents')
+        col.alter(type=LongText)
+    except Exception:
+        LOG.info(repr(stored_file))
+        LOG.exception(_('Exception while creating table.'))
+        raise
+
+
+def downgrade(migrate_engine):
+    raise NotImplementedError('Downgrade is unsupported.')

tuskar/db/sqlalchemy/models.py

@@ -22,6 +22,8 @@ from sqlalchemy import (Column, ForeignKey, Integer, String, Text)
 from sqlalchemy.ext.declarative import declarative_base
 from sqlalchemy.orm import relationship
 
+from tuskar.db.sqlalchemy.types import LongText
+
 
 sql_opts = [
     cfg.StrOpt('mysql_engine',
@@ -225,7 +227,7 @@ class StoredFile(Base):
     uuid = Column(String(length=36), primary_key=True)
 
     #: contents contains the full file contents as a string.
-    contents = Column(Text(), nullable=False)
+    contents = Column(LongText(), nullable=False)
 
     #: Object type flags the type of file that this is, i.e. template or
     #: environment file.

tuskar/db/sqlalchemy/types.py

@@ -0,0 +1,24 @@
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+from sqlalchemy.dialects import mysql
+from sqlalchemy import types
+
+
+class LongText(types.TypeDecorator):
+    impl = types.Text
+
+    def load_dialect_impl(self, dialect):
+        if dialect.name == 'mysql':
+            return dialect.type_descriptor(mysql.LONGTEXT())
+        else:
+            return self.impl