Add a table for attachments

This commit adds a model and migration for storing links to and metadata
about attachments in the StoryBoard database.

Change-Id: Ib2e291f5cc80222b226627d076ba3e1f5b88a454
Story: 2000679
Task: 3146

storyboard/db/migration/alembic_migrations/versions/067_add_an_attachments_table.py

@@ -0,0 +1,65 @@
+# 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.
+#
+
+"""Add an attachments table
+
+Revision ID: 067
+Revises: 066
+Create Date: 2019-01-27 16:07:04.427155
+
+"""
+
+# revision identifiers, used by Alembic.
+revision = '067'
+down_revision = '066'
+
+
+from alembic import op
+from oslo_log import log
+import sqlalchemy as sa
+
+import storyboard
+
+LOG = log.getLogger(__name__)
+
+
+def upgrade(active_plugins=None, options=None):
+    op.create_table('attachments',
+        sa.Column('id', sa.Integer(), nullable=False),
+        sa.Column('created_at', storyboard.db.decorators.UTCDateTime(),
+                  nullable=True),
+        sa.Column('updated_at', storyboard.db.decorators.UTCDateTime(),
+                  nullable=True),
+        sa.Column('name', sa.Unicode(length=255), nullable=False),
+        sa.Column('link', sa.UnicodeText(), nullable=False),
+        sa.Column('creator_id', sa.Integer(), nullable=False, index=True),
+        sa.Column('story_id', sa.Integer(), nullable=False, index=True),
+        sa.ForeignKeyConstraint(['creator_id'], ['users.id'], ),
+        sa.ForeignKeyConstraint(['story_id'], ['stories.id'], ),
+        sa.PrimaryKeyConstraint('id')
+    )
+
+    version_info = op.get_bind().engine.dialect.server_version_info
+    if version_info[-1] == "MariaDB":
+        # Removes fake mysql prefix
+        version_info = version_info[-4:]
+    if version_info[0] < 5 or version_info[0] == 5 and version_info[1] < 6:
+        LOG.warning(
+            "MySQL version is lower than 5.6. Skipping full-text index")
+        return
+
+    op.execute("ALTER TABLE attachments ADD FULLTEXT attachments_fti (name)")
+
+
+def downgrade(active_plugins=None, options=None):
+    op.drop_table('attachments')

storyboard/db/models.py

@@ -1,6 +1,7 @@
 # Copyright 2013 Hewlett-Packard Development Company, L.P.
 # Copyright 2013 Thierry Carrez <thierry@openstack.org>
 # Copyright 2015-2016 Codethink Ltd.
+# Copyright 2019 Adam Coldrick
 #
 # 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
@@ -360,6 +361,20 @@ class Task(FullText, ModelBuilder, Base):
                       "milestone_id"]
 
 
+class Attachment(FullText, ModelBuilder, Base):
+    __tablename__ = 'attachments'
+    __fulltext_columns__ = ['name']
+
+    name = Column(Unicode(CommonLength.top_large_length), nullable=False)
+    link = Column(UnicodeText(), nullable=False)
+    creator_id = Column(
+        Integer, ForeignKey('users.id'), nullable=False, index=True)
+    story_id = Column(
+        Integer, ForeignKey('stories.id'), nullable=False, index=True)
+
+    _public_fields = ["id", "name", "link", "creator_id", "story_id"]
+
+
 story_permissions = Table(
     'story_permissions', Base.metadata,
     Column('story_id', Integer, ForeignKey('stories.id')),