Migrations: Drop `generic_role*` tables

Drop the `generic_role*` tables, since what they were envisioned for can be
handled a different, (arguably) more simple way.

* migrations/auth/20221114_02_DKKjn-drop-generic-role-tables.py: new migration
* tests/unit/auth/test_migrations_drop_tables.py: test new migration

2 files changed, 103 insertions, 0 deletions

diff --git a/migrations/auth/20221114_02_DKKjn-drop-generic-role-tables.py b/migrations/auth/20221114_02_DKKjn-drop-generic-role-tables.py
new file mode 100644
index 0000000..e767aeb
--- /dev/null
+++ b/migrations/auth/20221114_02_DKKjn-drop-generic-role-tables.py
@@ -0,0 +1,39 @@
+"""
+Drop 'generic_role*' tables
+"""
+
+from yoyo import step
+
+__depends__ = {'20221114_01_n8gsF-create-generic-role-privileges-table'}
+
+steps = [
+    step(
+        """
+        DROP INDEX IF EXISTS
+            idx_tbl_generic_role_privileges_cols_generic_role_id
+        """,
+        """
+        CREATE INDEX IF NOT EXISTS
+            idx_tbl_generic_role_privileges_cols_generic_role_id
+        ON generic_role_privileges(generic_role_id)
+        """),
+    step(
+        "DROP TABLE IF EXISTS generic_role_privileges",
+        """
+        CREATE TABLE IF NOT EXISTS generic_role_privileges(
+            generic_role_id TEXT NOT NULL,
+            privilege_id TEXT NOT NULL,
+            PRIMARY KEY(generic_role_id, privilege_id),
+            FOREIGN KEY(generic_role_id) REFERENCES generic_roles(role_id),
+            FOREIGN KEY(privilege_id) REFERENCES privileges(privilege_id)
+        ) WITHOUT ROWID
+        """),
+    step(
+        "DROP TABLE IF EXISTS generic_roles",
+        """
+        CREATE TABLE IF NOT EXISTS generic_roles(
+            role_id TEXT PRIMARY KEY,
+            role_name TEXT NOT NULL
+        ) WITHOUT ROWID
+        """)
+]
diff --git a/tests/unit/auth/test_migrations_drop_tables.py b/tests/unit/auth/test_migrations_drop_tables.py
new file mode 100644
index 0000000..dfab3f6
--- /dev/null
+++ b/tests/unit/auth/test_migrations_drop_tables.py
@@ -0,0 +1,64 @@
+"""Test migrations that create tables"""
+from contextlib import closing
+
+import pytest
+import sqlite3
+
+from gn3.migrations import get_migration, apply_migrations, rollback_migrations
+from tests.unit.auth.conftest import (
+    apply_single_migration, rollback_single_migration, migrations_up_to)
+
+test_params = (
+    ("20221114_02_DKKjn-drop-generic-role-tables.py", "generic_roles"),
+    ("20221114_02_DKKjn-drop-generic-role-tables.py", "generic_role_privileges"))
+
+@pytest.mark.unit_test
+@pytest.mark.parametrize("migration_file,the_table", test_params)
+def test_drop_table(
+        auth_testdb_path, auth_migrations_dir, backend, all_migrations,
+        migration_file, the_table):
+    """
+    GIVEN: A database migration script to create table, `the_table`
+    WHEN: The migration is applied
+    THEN: Ensure that the table `the_table` is created
+    """
+    migration_path=f"{auth_migrations_dir}/{migration_file}"
+    older_migrations = migrations_up_to(migration_path, auth_migrations_dir)
+    the_migration = get_migration(migration_path)
+    apply_migrations(backend, older_migrations)
+    with closing(sqlite3.connect(auth_testdb_path)) as conn, closing(conn.cursor()) as cursor:
+        cursor.execute("SELECT name FROM sqlite_schema WHERE type='table'")
+        result_before_migration = cursor.fetchall()
+        apply_single_migration(backend, the_migration)
+        cursor.execute("SELECT name FROM sqlite_schema WHERE type='table'")
+        result_after_migration = cursor.fetchall()
+
+    rollback_migrations(backend, older_migrations + [the_migration])
+    assert the_table in [row[0] for row in result_before_migration]
+    assert the_table not in [row[0] for row in result_after_migration]
+
+@pytest.mark.unit_test
+@pytest.mark.parametrize("migration_file,the_table", test_params)
+def test_rollback_drop_table(
+        auth_testdb_path, auth_migrations_dir, backend, migration_file,
+        the_table):
+    """
+    GIVEN: A database migration script to create the table `the_table`
+    WHEN: The migration is rolled back
+    THEN: Ensure that the table `the_table` no longer exists
+    """
+    migration_path=f"{auth_migrations_dir}/{migration_file}"
+    older_migrations = migrations_up_to(migration_path, auth_migrations_dir)
+    the_migration = get_migration(migration_path)
+    apply_migrations(backend, older_migrations)
+    with closing(sqlite3.connect(auth_testdb_path)) as conn, closing(conn.cursor()) as cursor:
+        apply_single_migration(backend, the_migration)
+        cursor.execute("SELECT name FROM sqlite_schema WHERE type='table'")
+        result_after_migration = cursor.fetchall()
+        rollback_single_migration(backend, the_migration)
+        cursor.execute("SELECT name FROM sqlite_schema WHERE type='table'")
+        result_after_rollback = cursor.fetchall()
+
+    rollback_migrations(backend, older_migrations)
+    assert the_table not in [row[0] for row in result_after_migration]
+    assert the_table in [row[0] for row in result_after_rollback]