SQLAlchemy: Adjust DDL compiler improvements to emit warnings

src/crate/client/sqlalchemy/compiler.py

@@ -20,6 +20,7 @@
 # software solely pursuant to the terms of the relevant commercial agreement.
 
 import string
+import warnings
 from collections import defaultdict
 
 import sqlalchemy as sa
@@ -182,12 +183,16 @@ def visit_foreign_key_constraint(self, constraint, **kw):
  """
  CrateDB does not support foreign key constraints.
  """
+ warnings.warn("CrateDB does not support foreign key constraints, "
+ "they will be omitted when generating DDL statements.")
  return None
 
  def visit_unique_constraint(self, constraint, **kw):
  """
  CrateDB does not support unique key constraints.
  """
+ warnings.warn("CrateDB does not support unique constraints, "
+ "they will be omitted when generating DDL statements.")
  return None
 
 

src/crate/client/sqlalchemy/tests/compiler_test.py

@@ -18,6 +18,7 @@
 # However, if you have executed another commercial license agreement
 # with Crate these terms will supersede the license and you may use the
 # software solely pursuant to the terms of the relevant commercial agreement.
+import warnings
 from textwrap import dedent
 from unittest import mock, skipIf, TestCase
 from unittest.mock import MagicMock, patch
@@ -27,6 +28,9 @@
 
 import sqlalchemy as sa
 from sqlalchemy.sql import text, Update
+
+from crate.testing.util import ExtraAssertions
+
 try:
  from sqlalchemy.orm import declarative_base
 except ImportError:
@@ -288,7 +292,7 @@ def execute_wrapper(self, query, *args, **kwargs):
 
 
 @patch('crate.client.connection.Cursor', FakeCursor)
-class SqlAlchemyDDLCompilerTest(CompilerTestCase):
+class SqlAlchemyDDLCompilerTest(CompilerTestCase, ExtraAssertions):
  """
  Verify a few scenarios regarding the DDL compiler.
  """
@@ -330,26 +334,39 @@ class ItemStore(Base):
  )
  root = sa.orm.relationship(RootStore, back_populates="items")
 
- self.metadata.create_all(self.engine, tables=[RootStore.__table__], checkfirst=False)
- self.assertEqual(self.executed_statement, dedent("""
- CREATE TABLE testdrive.root (
- \tid INT NOT NULL, 
- \tname STRING, 
- \tPRIMARY KEY (id)
- )
-
- """)) # noqa: W291
-
- self.metadata.create_all(self.engine, tables=[ItemStore.__table__], checkfirst=False)
- self.assertEqual(self.executed_statement, dedent("""
- CREATE TABLE testdrive.item (
- \tid INT NOT NULL, 
- \tname STRING, 
- \troot_id INT, 
- \tPRIMARY KEY (id)
- )
-
- """)) # noqa: W291, W293
+ with warnings.catch_warnings(record=True) as w:
+
+ # Cause all warnings to always be triggered.
+ warnings.simplefilter("always")
+
+ # Verify SQL DDL statement.
+ self.metadata.create_all(self.engine, tables=[RootStore.__table__], checkfirst=False)
+ self.assertEqual(self.executed_statement, dedent("""
+ CREATE TABLE testdrive.root (
+ \tid INT NOT NULL, 
+ \tname STRING, 
+ \tPRIMARY KEY (id)
+ )
+ 
+ """)) # noqa: W291, W293
+
+ # Verify SQL DDL statement.
+ self.metadata.create_all(self.engine, tables=[ItemStore.__table__], checkfirst=False)
+ self.assertEqual(self.executed_statement, dedent("""
+ CREATE TABLE testdrive.item (
+ \tid INT NOT NULL, 
+ \tname STRING, 
+ \troot_id INT, 
+ \tPRIMARY KEY (id)
+ )
+ 
+ """)) # noqa: W291, W293
+
+ # Verify if corresponding warning is emitted.
+ self.assertEqual(len(w), 1)
+ self.assertIsSubclass(w[-1].category, UserWarning)
+ self.assertIn("CrateDB does not support foreign key constraints, "
+ "they will be omitted when generating DDL statements.", str(w[-1].message))
 
  def test_ddl_with_unique_key(self):
  """
@@ -366,12 +383,24 @@ class FooBar(Base):
  id = sa.Column(sa.Integer, primary_key=True)
  name = sa.Column(sa.String, unique=True)
 
- self.metadata.create_all(self.engine, tables=[FooBar.__table__], checkfirst=False)
- self.assertEqual(self.executed_statement, dedent("""
- CREATE TABLE testdrive.foobar (
- \tid INT NOT NULL, 
- \tname STRING, 
- \tPRIMARY KEY (id)
- )
-
- """)) # noqa: W291
+ with warnings.catch_warnings(record=True) as w:
+
+ # Cause all warnings to always be triggered.
+ warnings.simplefilter("always")
+
+ # Verify SQL DDL statement.
+ self.metadata.create_all(self.engine, tables=[FooBar.__table__], checkfirst=False)
+ self.assertEqual(self.executed_statement, dedent("""
+ CREATE TABLE testdrive.foobar (
+ \tid INT NOT NULL, 
+ \tname STRING, 
+ \tPRIMARY KEY (id)
+ )
+ 
+ """)) # noqa: W291, W293
+
+ # Verify if corresponding warning is emitted.
+ self.assertEqual(len(w), 1)
+ self.assertIsSubclass(w[-1].category, UserWarning)
+ self.assertIn("CrateDB does not support unique constraints, "
+ "they will be omitted when generating DDL statements.", str(w[-1].message))