Fix model sync for SQLite

This code fixes the situation when several
models are mismatched for SQLite because of
type inconsistencies between Integer and
BigInteger in sqlalchemy.

Change-Id: I52b3a0158db8e3dc48f19509d1f9f80420ee40ea
Closes-bug: #1526804
Closes-bug: #1526675

glance/db/sqlalchemy/api.py

@@ -303,6 +303,10 @@ def _get_default_column_value(column_type):
         'integer': 0,
         'string': ''
     }
+
+    if isinstance(column_type, sa_sql.type_api.Variant):
+        return _get_default_column_value(column_type.impl)
+
     return type_schema[column_type.__visit_name__]
 
 

glance/db/sqlalchemy/models.py

@@ -26,7 +26,6 @@ from sqlalchemy import BigInteger
 from sqlalchemy import Boolean
 from sqlalchemy import Column
 from sqlalchemy import DateTime
-from sqlalchemy.ext.compiler import compiles
 from sqlalchemy.ext.declarative import declarative_base
 from sqlalchemy import ForeignKey
 from sqlalchemy import Index
@@ -44,11 +43,6 @@ from glance.common import timeutils
 BASE = declarative_base()
 
 
-@compiles(BigInteger, 'sqlite')
-def compile_big_int_sqlite(type_, compiler, **kw):
-    return 'INTEGER'
-
-
 class JSONEncodedDict(TypeDecorator):
     """Represents an immutable structure as a json-encoded string"""
 
@@ -131,8 +125,8 @@ class Image(BASE, GlanceBase):
     name = Column(String(255))
     disk_format = Column(String(20))
     container_format = Column(String(20))
-    size = Column(BigInteger)
-    virtual_size = Column(BigInteger)
+    size = Column(BigInteger().with_variant(Integer, "sqlite"))
+    virtual_size = Column(BigInteger().with_variant(Integer, "sqlite"))
     status = Column(String(30), nullable=False)
     is_public = Column(Boolean, nullable=False, default=False)
     checksum = Column(String(32))

glance/db/sqlalchemy/models_artifacts.py

@@ -109,13 +109,15 @@ class Artifact(BASE, ArtifactBase):
                 default=lambda: str(uuid.uuid4()))
     name = Column(String(255), nullable=False)
     type_name = Column(String(255), nullable=False)
-    type_version_prefix = Column(BigInteger, nullable=False)
+    type_version_prefix = Column(BigInteger().with_variant(Integer, "sqlite"),
+                                 nullable=False)
     type_version_suffix = Column(String(255))
     type_version_meta = Column(String(255))
     type_version = composite(semver_db.DBVersion, type_version_prefix,
                              type_version_suffix, type_version_meta,
                              comparator_factory=semver_db.VersionComparator)
-    version_prefix = Column(BigInteger, nullable=False)
+    version_prefix = Column(BigInteger().with_variant(Integer, "sqlite"),
+                            nullable=False)
     version_suffix = Column(String(255))
     version_meta = Column(String(255))
     version = composite(semver_db.DBVersion, version_prefix,
@@ -294,7 +296,8 @@ class ArtifactBlob(BASE, ArtifactBase):
                          nullable=False)
     name = Column(String(255), nullable=False)
     item_key = Column(String(329))
-    size = Column(BigInteger(), nullable=False)
+    size = Column(BigInteger().with_variant(Integer, "sqlite"),
+                  nullable=False)
     checksum = Column(String(32))
     position = Column(Integer)
     artifact = relationship(Artifact,

glance/tests/unit/test_migrations.py

@@ -42,6 +42,7 @@ from oslo_utils import uuidutils
 from six.moves import range
 import sqlalchemy
 from sqlalchemy import inspect
+import sqlalchemy.types as types
 
 from glance.common import crypt
 from glance.common import exception
@@ -1887,6 +1888,28 @@ class ModelsMigrationSyncMixin(object):
     def db_sync(self, engine):
         migration.db_sync(engine=engine)
 
+    # TODO(akamyshikova): remove this method as soon as comparison with Variant
+    # will be implemented in oslo.db or alembic
+    def compare_type(self, ctxt, insp_col, meta_col, insp_type, meta_type):
+        if isinstance(meta_type, types.Variant):
+            meta_orig_type = meta_col.type
+            insp_orig_type = insp_col.type
+            meta_col.type = meta_type.impl
+            insp_col.type = meta_type.impl
+
+            try:
+                return self.compare_type(ctxt, insp_col, meta_col, insp_type,
+                                         meta_type.impl)
+            finally:
+                meta_col.type = meta_orig_type
+                insp_col.type = insp_orig_type
+        else:
+            ret = super(ModelsMigrationSyncMixin, self).compare_type(
+                ctxt, insp_col, meta_col, insp_type, meta_type)
+            if ret is not None:
+                return ret
+            return ctxt.impl.compare_type(insp_col, meta_col)
+
     def include_object(self, object_, name, type_, reflected, compare_to):
         if name in ['migrate_version'] and type_ == 'table':
             return False