Add Database Guard on Generator

grace/database.py

@@ -5,9 +5,16 @@
 from alembic.util.exc import CommandError
 
 from .application import Application
+from .exceptions import ConfigError
 
 
 def generate_migration(app: Application, message: str):
+    if not app.has_database:
+        raise ConfigError(
+            "This project has no database configured. "
+            "Run 'grace generate database' to add one."
+        )
+
     try:
         alembic_cfg = Config("alembic.ini")
         alembic_cfg.config_ini_section = app.environment

grace/generators/migration_generator.py

@@ -1,4 +1,4 @@
-from logging import info
+from logging import info, warning
 
 from click.core import Argument
 
@@ -22,11 +22,18 @@ def generate(self, message: str):
         grace generate migration "Add Greeting model"
         ```
         """
-        info(f"Generating migration '{message}'")
-
         if not self.app:
             raise ValueError("app is not initialized")
 
+        if not self.app.has_database:
+            warning(
+                "This project has no database configured. "
+                "Run 'grace generate database' to add one."
+            )
+            return
+
+        info(f"Generating migration '{message}'")
+
         generate_migration(self.app, message)
 
     def validate(self, message: str, **_kwargs) -> bool:

grace/generators/model_generator.py

@@ -1,4 +1,4 @@
-from logging import info
+from logging import info, warning
 from re import match
 
 from click.core import Argument
@@ -33,6 +33,16 @@ def generate(self, name: str, params: tuple[str]):
         grace generate model Greeting message:String lang:String
         ```
         """
+        if not self.app:
+            raise ValueError("app is not initialized")
+
+        if not self.app.has_database:
+            warning(
+                "This project has no database configured. "
+                "Run 'grace generate database' to add one."
+            )
+            return
+
         info(f"Generating model '{name}'")
 
         columns, types = self.extract_columns(params)
@@ -49,9 +59,6 @@ def generate(self, name: str, params: tuple[str]):
             output_dir="bot/models",
         )
 
-        if not self.app:
-            raise ValueError("app is not initialized")
-
         generate_migration(self.app, f"Create {name}")
 
     def validate(self, name: str, **_kwargs) -> bool:

tests/generators/test_migration_generator.py

@@ -0,0 +1,43 @@
+from unittest.mock import MagicMock
+
+import pytest
+
+from grace.generators.migration_generator import MigrationGenerator
+
+
+@pytest.fixture
+def generator():
+    generator = MigrationGenerator()
+    generator.app = MagicMock(has_database=True)
+    return generator
+
+
+def test_generate_without_app__expect_value_error(generator):
+    generator.app = None
+
+    with pytest.raises(ValueError):
+        generator.generate("Add Greeting model")
+
+
+def test_generate_without_database__expect_warning_and_no_migration(
+    mocker, generator, caplog
+):
+    generator.app.has_database = False
+    mock_generate_migration = mocker.patch(
+        "grace.generators.migration_generator.generate_migration"
+    )
+
+    generator.generate("Add Greeting model")
+
+    mock_generate_migration.assert_not_called()
+    assert "no database configured" in caplog.text.lower()
+
+
+def test_generate_with_database__expect_migration_generated(mocker, generator):
+    mock_generate_migration = mocker.patch(
+        "grace.generators.migration_generator.generate_migration"
+    )
+
+    generator.generate("Add Greeting model")
+
+    mock_generate_migration.assert_called_once_with(generator.app, "Add Greeting model")

tests/generators/test_model_generator.py

@@ -0,0 +1,46 @@
+from unittest.mock import MagicMock
+
+import pytest
+
+from grace.generator import Generator
+from grace.generators.model_generator import ModelGenerator
+
+
+@pytest.fixture
+def generator():
+    generator = ModelGenerator()
+    generator.app = MagicMock(has_database=True)
+    return generator
+
+
+def test_generate_without_app__expect_value_error(generator):
+    generator.app = None
+
+    with pytest.raises(ValueError):
+        generator.generate("Greeting", ("message:String",))
+
+
+def test_generate_without_database__expect_no_file_and_warning(
+    mocker, generator, caplog
+):
+    generator.app.has_database = False
+    mock_generate_file = mocker.patch.object(Generator, "generate_file")
+
+    generator.generate("Greeting", ("message:String",))
+
+    mock_generate_file.assert_not_called()
+    assert "no database configured" in caplog.text.lower()
+
+
+def test_generate_with_database__expect_model_file_and_migration_generated(
+    mocker, generator
+):
+    mock_generate_file = mocker.patch.object(Generator, "generate_file")
+    mock_generate_migration = mocker.patch(
+        "grace.generators.model_generator.generate_migration"
+    )
+
+    generator.generate("Greeting", ("message:String",))
+
+    mock_generate_file.assert_called_once()
+    mock_generate_migration.assert_called_once_with(generator.app, "Create Greeting")

tests/test_database.py

@@ -0,0 +1,23 @@
+from unittest.mock import MagicMock
+
+import pytest
+
+from grace.database import generate_migration
+from grace.exceptions import ConfigError
+
+
+def test_generate_migration_without_database__expect_config_error():
+    app = MagicMock(has_database=False)
+
+    with pytest.raises(ConfigError):
+        generate_migration(app, "Add Greeting model")
+
+
+def test_generate_migration_with_database__expect_revision_called(mocker):
+    app = MagicMock(has_database=True, environment="development")
+    mock_revision = mocker.patch("grace.database.revision")
+    mocker.patch("grace.database.Config")
+
+    generate_migration(app, "Add Greeting model")
+
+    mock_revision.assert_called_once()