db-migrate: backport some changes for py3 compat.

rhodecode/lib/dbmigrate/migrate/changeset/__init__.py

@@ -12,10 +12,11 @@ from sqlalchemy import __version__ as _sa_version
 
 warnings.simplefilter('always', DeprecationWarning)
 
-_sa_version = tuple(int(re.match("\d+", x).group(0))
-                    for x in _sa_version.split("."))
+_sa_version = tuple(int(re.match("\d+", x).group(0)) for x in _sa_version.split("."))
 SQLA_07 = _sa_version >= (0, 7)
 SQLA_08 = _sa_version >= (0, 8)
+SQLA_09 = _sa_version >= (0, 9)
+SQLA_10 = _sa_version >= (1, 0)
 
 del re
 del _sa_version
@@ -23,8 +24,8 @@ del _sa_version
 from rhodecode.lib.dbmigrate.migrate.changeset.schema import *
 from rhodecode.lib.dbmigrate.migrate.changeset.constraint import *
 
-sqlalchemy.schema.Table.__bases__ += (ChangesetTable,)
-sqlalchemy.schema.Column.__bases__ += (ChangesetColumn,)
-sqlalchemy.schema.Index.__bases__ += (ChangesetIndex,)
+sqlalchemy.schema.Table.__bases__ += (ChangesetTable, )
+sqlalchemy.schema.Column.__bases__ += (ChangesetColumn, )
+sqlalchemy.schema.Index.__bases__ += (ChangesetIndex, )
 
-sqlalchemy.schema.DefaultClause.__bases__ += (ChangesetDefaultClause,)
+sqlalchemy.schema.DefaultClause.__bases__ += (ChangesetDefaultClause, )

rhodecode/lib/dbmigrate/migrate/changeset/ansisql.py

@@ -97,7 +97,6 @@ class ANSIColumnGenerator(AlterTableVisitor, SchemaGenerator):
 
         table = self.start_alter_table(column)
         self.append("ADD ")
-
         self.append(self.get_column_specification(column))
 
         for cons in column.constraints:

rhodecode/lib/dbmigrate/migrate/changeset/constraint.py

@@ -111,7 +111,7 @@ class ForeignKeyConstraint(ConstraintChangeset, schema.ForeignKeyConstraint):
         refcolnames, reftable = self._normalize_columns(refcolumns,
                                                         table_name=True)
         super(ForeignKeyConstraint, self).__init__(
-            colnames, refcolnames, *args,**kwargs
+            colnames, refcolnames, *args, **kwargs
         )
         if table is not None:
             self._set_parent(table)

rhodecode/lib/dbmigrate/migrate/changeset/databases/sqlite.py

@@ -3,11 +3,15 @@
 
    .. _`SQLite`: http://www.sqlite.org/
 """
-from UserDict import DictMixin
+try:  # Python 3
+    from collections.abc import MutableMapping as DictMixin
+except ImportError:  # Python 2
+    from UserDict import DictMixin
 from copy import copy
 import re
 
 from sqlalchemy.databases import sqlite as sa_base
+from sqlalchemy.schema import ForeignKeyConstraint
 from sqlalchemy.schema import UniqueConstraint
 
 from rhodecode.lib.dbmigrate.migrate import exceptions

rhodecode/lib/dbmigrate/migrate/changeset/schema.py

@@ -1,10 +1,13 @@
 """
    Schema module providing common schema operations.
 """
+import abc
+try:  # Python 3
+    from collections.abc import MutableMapping as DictMixin
+except ImportError:  # Python 2
+    from UserDict import DictMixin
 import warnings
 
-from UserDict import DictMixin
-
 import sqlalchemy
 
 from sqlalchemy.schema import ForeignKeyConstraint

rhodecode/lib/dbmigrate/migrate/changeset/util.py

@@ -1,6 +1,17 @@
 """
 Safe quoting method
 """
+from rhodecode.lib.dbmigrate.migrate.changeset import SQLA_10
+
+
+def fk_column_names(constraint):
+    if SQLA_10:
+        return [
+            constraint.columns[key].name for key in constraint.column_keys]
+    else:
+        return [
+            element.parent.name for element in constraint.elements]
+
 
 def safe_quote(obj):
     # this is the SQLA 0.9 approach

rhodecode/lib/dbmigrate/migrate/exceptions.py

@@ -27,6 +27,10 @@ class InvalidVersionError(ControlledSchemaError):
     """Invalid version number."""
 
 
+class VersionNotFoundError(KeyError):
+    """Specified version is not present."""
+
+
 class DatabaseNotControlledError(ControlledSchemaError):
     """Database should be under version control, but it's not."""