PSCE-239: feat: adds validation for YAML trestle rules (#52)

* feat(transformers): initial validation handler from pre-validation before pydantic

Signed-off-by: Jennifer Power <[email protected]>

* chore: fixes spelling error on csv_transformer.py comment

Signed-off-by: Jennifer Power <[email protected]>

* feat(task): adds collection of validation errors in rules task

Updates the rules transform task to make sure all errors for a
component defintion are collection during transformation and presented
back to the user to make errors easier to address at one time.

Signed-off-by: Jennifer Power <[email protected]>

---------

Signed-off-by: Jennifer Power <[email protected]>

tests/trestlebot/transformers/test_validations.py

@@ -0,0 +1,60 @@
+#!/usr/bin/python
+
+#    Copyright 2023 Red Hat, Inc.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+"""Test for Validations."""
+from typing import Any, Dict
+
+from trestlebot.transformers.validations import (
+    ValidationHandler,
+    ValidationOutcome,
+    parameter_validation,
+)
+
+
+def test_parameter_validation(valid_rule_data: Dict[str, Any]) -> None:
+    """Test parameter validation with valid data."""
+    result: ValidationOutcome = ValidationOutcome(errors=[], valid=True)
+    parameter_validation(valid_rule_data, result)
+    assert result.valid
+
+
+def test_parameter_validation_with_error(
+    invalid_param_rule_data: Dict[str, Any]
+) -> None:
+    """Test parameter validation with invalid parameter."""
+    result: ValidationOutcome = ValidationOutcome(errors=[], valid=True)
+    parameter_validation(invalid_param_rule_data, result)
+    assert not result.valid
+    assert len(result.errors) == 1
+    assert (
+        result.errors[0].error_message
+        == "Default value must be one of the alternative values"
+    )
+
+
+def test_parameter_validation_with_handler(
+    invalid_param_rule_data: Dict[str, Any]
+) -> None:
+    """Test parameter validation with handler."""
+    result: ValidationOutcome = ValidationOutcome(errors=[], valid=True)
+    handler = ValidationHandler(parameter_validation)
+    handler.handle(invalid_param_rule_data, result)
+    assert not result.valid
+    assert len(result.errors) == 1
+    assert (
+        result.errors[0].error_message
+        == "Default value must be one of the alternative values"
+    )

tests/trestlebot/transformers/test_yaml_transformer.py

@@ -21,6 +21,7 @@
 from tests.testutils import YAML_TEST_DATA_PATH
 from trestlebot.transformers.base_transformer import RulesTransformerException
 from trestlebot.transformers.trestle_rule import TrestleRule
+from trestlebot.transformers.validations import ValidationHandler, parameter_validation
 from trestlebot.transformers.yaml_transformer import (
     FromRulesYAMLTransformer,
     ToRulesYAMLTransformer,
@@ -88,6 +89,24 @@ def test_rules_transform_with_invalid_rule() -> None:
         transformer.transform(rule_file_info)
 
 
+def test_rules_transform_with_additional_validation() -> None:
+    """Test rules transform with additional validation."""
+    # load rule from path and close the file
+    # get the file info as a string
+    rule_path = YAML_TEST_DATA_PATH / "test_rule_invalid_params.yaml"
+    rule_file = open(rule_path, "r")
+    rule_file_info = rule_file.read()
+    rule_file.close()
+    validation_handler_chain = ValidationHandler(parameter_validation)
+    transformer = ToRulesYAMLTransformer(validation_handler_chain)
+
+    with pytest.raises(
+        RulesTransformerException,
+        match=".*Default value must be one of the alternative values",
+    ):
+        transformer.transform(rule_file_info)
+
+
 def test_read_write_integration(test_rule: TrestleRule) -> None:
     """Test read/write integration."""
     from_rules_transformer = FromRulesYAMLTransformer()

trestlebot/tasks/rule_transform_task.py

@@ -93,6 +93,10 @@ def _transform_components(self, component_definition_path: pathlib.Path) -> None
         logger.debug(
             f"Transforming rules for component definition {component_definition_path.name}"
         )
+
+        # To report all rule errors at once, we collect them in a list and
+        # pretty print them in a raised exception
+        transformation_errors: List[str] = []
         for component in self.iterate_models(component_definition_path):
             for rule_path in self.iterate_models(component):
                 # Load the rule into memory as a stream to process
@@ -102,10 +106,16 @@ def _transform_components(self, component_definition_path: pathlib.Path) -> None
                     rule = self._rule_transformer.transform(rule_stream)
                     csv_builder.add_row(rule)
                 except RulesTransformerException as e:
-                    raise TaskException(
+                    transformation_errors.append(
                         f"Failed to transform rule {rule_path.name}: {e}"
                     )
 
+        if len(transformation_errors) > 0:
+            raise TaskException(
+                f"Failed to transform rules for component definition {component_definition_path.name}: \
+                    \n{', '.join(transformation_errors)}"
+            )
+
         if csv_builder.row_count == 0:
             raise TaskException(
                 f"No rules found for component definition {component_definition_path.name}"

trestlebot/transformers/csv_transformer.py

@@ -14,7 +14,7 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-"""CSV Tranformer for rule authoring."""
+"""CSV Transformer for rule authoring."""
 
 import csv
 import json

trestlebot/transformers/validations.py

@@ -0,0 +1,100 @@
+#!/usr/bin/python
+
+#    Copyright 2023 Red Hat, Inc.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+"""
+Trestle Validation for rule authoring.
+
+This is meant to be extensible for future validations.
+Base rule validation and utility functions are defined here.
+"""
+
+import logging
+from typing import Any, Callable, Dict, List, Optional
+
+from pydantic import BaseModel
+
+from trestlebot import const
+
+
+logger = logging.getLogger(__name__)
+
+
+class RuleValidationError(BaseModel):
+    """RuleValidationError model."""
+
+    field_name: str
+    error_message: str
+
+
+class ValidationOutcome(BaseModel):
+    """ValidationOutcome model."""
+
+    errors: List[RuleValidationError]
+    valid: bool
+
+
+class ValidationHandler:
+    def __init__(  # type: ignore
+        self, validate_fn: Callable[[Any, ValidationOutcome], None], next_handler=None
+    ) -> None:
+        self.validate_fn: Callable[[Any, ValidationOutcome], None] = validate_fn
+        self.next_handler: Optional[ValidationHandler] = next_handler
+
+    def handle(self, data: Any, result: ValidationOutcome) -> None:
+        self.validate_fn(data, result)
+        if self.next_handler:
+            self.next_handler.handle(data, result)
+
+
+# TODO(jpower432): Create a class for Profile validation to ensure unique
+# entries exists in the workspace.
+
+
+def parameter_validation(data: Dict[str, Any], result: ValidationOutcome) -> None:
+    """Parameter logic additions validation."""
+    rule_info: Dict[str, Any] = data.get(const.RULE_INFO_TAG, {})
+    parameter_data: Dict[str, Any] = rule_info.get(const.PARAMETER, {})
+
+    if not parameter_data:
+        logger.debug("No parameter data found")
+        return  # No parameter data, nothing to validate
+
+    default_value = parameter_data.get(const.DEFAULT_VALUE, "")
+    alternative_values: Dict[str, Any] = parameter_data.get(
+        const.ALTERNATIVE_VALUES, {}
+    )
+
+    if not default_value:
+        add_validation_error(result, const.PARAMETER, "Default value is required")
+
+    if not alternative_values:
+        add_validation_error(result, const.PARAMETER, "Alternative values are required")
+
+    default_value_alt = alternative_values.get("default", "")
+
+    if not default_value_alt or default_value_alt != default_value:
+        add_validation_error(
+            result,
+            const.PARAMETER,
+            "Default value must be one of the alternative values",
+        )
+
+
+def add_validation_error(result: ValidationOutcome, field: str, error_msg: str) -> None:
+    """Add a validation error to the result."""
+    validation_error = RuleValidationError(field_name=field, error_message=error_msg)
+    result.errors.append(validation_error)
+    result.valid = False

trestlebot/transformers/yaml_transformer.py

@@ -18,7 +18,7 @@
 import logging
 import pathlib
 from io import StringIO
-from typing import Any, Dict
+from typing import Any, Dict, Optional
 
 from pydantic import ValidationError
 from ruamel.yaml import YAML
@@ -35,6 +35,7 @@
     Profile,
     TrestleRule,
 )
+from trestlebot.transformers.validations import ValidationHandler, ValidationOutcome
 
 
 logger = logging.getLogger(__name__)
@@ -43,8 +44,9 @@
 class ToRulesYAMLTransformer(ToRulesTransformer):
     """Interface for YAML transformer to Rules model."""
 
-    def __init__(self) -> None:
+    def __init__(self, validator: Optional[ValidationHandler] = None) -> None:
         """Initialize."""
+        self.validator: Optional[ValidationHandler] = validator
         super().__init__()
 
     def transform(self, blob: str) -> TrestleRule:
@@ -53,6 +55,15 @@ def transform(self, blob: str) -> TrestleRule:
             yaml = YAML(typ="safe")
             yaml_data: Dict[str, Any] = yaml.load(blob)
 
+            logger.debug("Executing pre-validation on YAML data")
+            if self.validator is not None:
+                result = ValidationOutcome(errors=[], valid=True)
+                self.validator.handle(yaml_data, result)
+                if not result.valid:
+                    raise RulesTransformerException(
+                        f"Invalid YAML file: {result.errors}"
+                    )
+
             rule_info_data = yaml_data[const.RULE_INFO_TAG]
 
             profile_data = rule_info_data[const.PROFILE]