Use importlib.import_module instead of __import__. Add error logic wh…

…en encountering invalid package/module when loading Pydantic models from an external package. Minor changes to address feedback.

docs/custom_validators.md

@@ -25,7 +25,7 @@ by providing a class-level `id` variable.
 
 Helper functions are provided to add pass/fail results:
 
-```
+```python
 def add_validation_error(self, message: str, **kwargs):
     """Add validator error to results.
     Args:
@@ -39,6 +39,7 @@ def add_validation_pass(self, **kwargs):
       kwargs (optional): additional arguments to add to ValidationResult when required
     """
 ```
+
 In most cases, you will not need to provide kwargs. However, if you find a use case that requires updating other fields
 in the ValidationResult, you can send the key/value pairs to update the result directly. This is for advanced users only.
 
@@ -58,7 +59,7 @@ the following criteria:
    * `operator`: Operator to use for comparison between left and right hand side of expression
    * `error`: Message to report when validation fails
 
-### Supported operators:
+### Supported operators
 
 The class provides the following operators for basic use cases:
 
@@ -73,10 +74,11 @@ The class provides the following operators for basic use cases:
 
 If you require additional logic or need to compare other types, use the BaseValidation class and create your own validate method.
 
-### Examples:
+### Examples
 
 #### Basic
-```
+
+```python
 from schema_enforcer.schemas.validator import JmesPathModelValidation
 
 class CheckInterface(JmesPathModelValidation):  # pylint: disable=too-few-public-methods
@@ -89,7 +91,8 @@ class CheckInterface(JmesPathModelValidation):  # pylint: disable=too-few-public
 ```
 
 #### With compiled jmespath expression
-```
+
+```python
 import jmespath
 from schema_enforcer.schemas.validator import JmesPathModelValidation
 
@@ -113,6 +116,8 @@ Schema Enforcer supports utilizing Pydantic models for validation. Pydantic mode
 
 Both methods will replace the Pydantic `BaseModel` with the `PydanticValidation` class that provides the required `validate` method that uses the `model_validate` method to validate data. The model is set to the original Pydantic model to validate data against.
 
+### Pydantic Models in External Libraries
+
 ```python
 class PydanticValidation(BaseValidation):
     """Basic wrapper for Pydantic models to be used as validators."""
@@ -138,11 +143,22 @@ class PydanticValidation(BaseValidation):
             self.add_validation_error(str(err))
 ```
 
-### Storing in Validators Directory
+### Pydantic Models in Validators Directory
+
+The Pydantic models can be located in any Python file within this directory (new or existing). The only requirement is these are valid Pydantic `BaseModel` subclasses.
+
+These will be loaded and can be referenced by their class name. For example, `CheckHostname` will show up as `CheckHostname`.
+
+```python
+"""Validate hostname is valid."""
+from pydantic import BaseModel
 
-The Pydantic models can be located in any Python file within this directory. The only requirement is these are valid Pydantic `BaseModel` subclasses.
 
-These will be loaded and can be referenced by their class name. For example, `Hostname` will show up as `Hostname`.
+class CheckHostname(BaseModel):
+    """Validate hostname is valid."""
+
+    hostname: str
+```
 
 ```yaml
 # jsonschema: Hostname

schema_enforcer/schemas/validator.py

@@ -5,6 +5,7 @@
 from __future__ import annotations
 from typing import List, Union
 import pkgutil
+import importlib
 import inspect
 import jmespath
 from pydantic import BaseModel, ValidationError
@@ -25,21 +26,15 @@ def add_validation_error(self, message: str, **kwargs):
           message (str): error message
           kwargs (optional): additional arguments to add to ValidationResult when required
         """
-        self._results.append(
-            ValidationResult(
-                result="FAIL", schema_id=self.id, message=message, **kwargs
-            )
-        )
+        self._results.append(ValidationResult(result="FAIL", schema_id=self.id, message=message, **kwargs))
 
     def add_validation_pass(self, **kwargs):
         """Add validator pass to results.
 
         Args:
           kwargs (optional): additional arguments to add to ValidationResult when required
         """
-        self._results.append(
-            ValidationResult(result="PASS", schema_id=self.id, **kwargs)
-        )
+        self._results.append(ValidationResult(result="PASS", schema_id=self.id, **kwargs))
 
     def get_results(self) -> list[ValidationResult]:
         """Return all validation results for this validator."""
@@ -120,9 +115,7 @@ def validate(self, data: dict, strict: bool = False):
 def is_validator(obj) -> bool:
     """Returns True if the object is a BaseValidation or JmesPathModelValidation subclass."""
     try:
-        return (
-            issubclass(obj, BaseValidation) or issubclass(obj, BaseModel)
-        ) and obj not in (
+        return (issubclass(obj, BaseValidation) or issubclass(obj, BaseModel)) and obj not in (
             BaseModel,
             BaseValidation,
             JmesPathModelValidation,
@@ -138,9 +131,7 @@ def pydantic_validation_factory(orig_model) -> PydanticValidation:
         (PydanticValidation,),
         {
             "id": f"{orig_model.id}",
-            "top_level_properties": set(
-                [property for property in orig_model.model_fields]
-            ),
+            "top_level_properties": set([property for property in orig_model.model_fields]),
             "model": orig_model,
         },
     )
@@ -153,20 +144,23 @@ def load_pydantic_validators(
     validators = {}
     for package in model_packages:
         module_name, attr = package.split(":")
-        module = __import__(module_name, fromlist=[attr])
-        manager = getattr(module, attr)
+        try:
+            module = importlib.import_module(module_name)
+        except ModuleNotFoundError:
+            print(f"Unable to load the validator {package}, the module ({module_name}) does not exist.")
+            continue
+
+        manager = getattr(module, attr, None)
+        if not manager:
+            print(f"Unable to load the validator {package}, the module or attribute ({attr}) does not exist.")
+            continue
+
         for model in manager.models:
-            model.id = (
-                f"{manager.prefix}/{model.__name__}"
-                if manager.prefix
-                else model.__name__
-            )
+            model.id = f"{manager.prefix}/{model.__name__}" if manager.prefix else model.__name__
             cls = pydantic_validation_factory(model)
 
             if cls.id in validators:
-                print(
-                    f"Unable to load the validator {cls.id}, there is already a validator with the same name."
-                )
+                print(f"Unable to load the validator {cls.id}, there is already a validator with the same name.")
                 continue
 
             validators[cls.id] = cls()

tests/fixtures/test_validators_pydantic/inventory/host_vars/az_phx_pe01/dns.yml

@@ -1,3 +1,4 @@
+---
 # jsonschema: pydantic/Dns
 dns_servers:
   - "8.8.8.8"

tests/fixtures/test_validators_pydantic/inventory/host_vars/co_den_p01/dns.yml

@@ -1,3 +1,4 @@
+---
 # jsonschema: pydantic/Dns
 dns_servers:
   - "8.8.8.8"

tests/fixtures/test_validators_pydantic/inventory_fail/host_vars/az_phx_pe01/dns.yml

@@ -1,3 +1,4 @@
+---
 # jsonschema: pydantic/Dns
 dns_servers:
   - "8.8.8.8"

tests/fixtures/test_validators_pydantic/inventory_fail/host_vars/co_den_p01/dns.yml

@@ -1,3 +1,4 @@
+---
 # jsonschema: pydantic/Dns
 dns_servers:
   - "8.8.8.8"

tests/fixtures/test_validators_pydantic/pydantic_validators/models/interfaces.py

@@ -1,4 +1,4 @@
-"""Validate hostname is valid."""
+"""Validate interfaces are valid."""
 
 from enum import Enum
 from typing import Dict, Optional
@@ -22,6 +22,6 @@ class Interface(BaseModel):
 
 
 class Interfaces(BaseModel):
-    """Validate hostname is valid."""
+    """Validate interfaces are valid."""
 
     interfaces: Dict[str, Interface]

tests/test_ansible_inventory.py

@@ -10,7 +10,7 @@
 
 
 @pytest.fixture(scope="module")
-def ansible_inv():  # pylint: disable=unused-argument
+def ansible_inv():
     """Ansible inventory fixture."""
     return AnsibleInventory(INVENTORY_DIR)
 
@@ -55,7 +55,10 @@ def test_get_hosts_containing_var(ansible_inv):
 
 def test_get_host_vars(ansible_inv):
     expected = {
-        "dns_servers": [{"address": "10.7.7.7", "vrf": "mgmt"}, {"address": "10.8.8.8"}],
+        "dns_servers": [
+            {"address": "10.7.7.7", "vrf": "mgmt"},
+            {"address": "10.8.8.8"},
+        ],
         "group_names": ["ios", "na", "nyc"],
         "inventory_hostname": "host3",
         "ntp_servers": [{"address": "10.3.3.3"}],
@@ -80,7 +83,10 @@ def test_get_host_vars(ansible_inv):
 
 def test_get_clean_host_vars(ansible_inv):
     expected = {
-        "dns_servers": [{"address": "10.7.7.7", "vrf": "mgmt"}, {"address": "10.8.8.8"}],
+        "dns_servers": [
+            {"address": "10.7.7.7", "vrf": "mgmt"},
+            {"address": "10.8.8.8"},
+        ],
         "os_dns": [{"address": "10.7.7.7", "vrf": "mgmt"}, {"address": "10.8.8.8"}],
         "region_dns": [{"address": "10.1.1.1", "vrf": "mgmt"}, {"address": "10.2.2.2"}],
         "ntp_servers": [{"address": "10.3.3.3"}],

tests/test_schemas_pydantic_validators.py

@@ -20,9 +20,7 @@
         "pydantic_validators.models:manager1",
         "pydantic_validators.models:manager2",
     ],
-    "data_file_search_directories": [
-        f"{FIXTURE_DIR}/test_validators_pydantic/inventory"
-    ],
+    "data_file_search_directories": [f"{FIXTURE_DIR}/test_validators_pydantic/inventory"],
     "ansible_inventory": f"{FIXTURE_DIR}/test_validators_pydantic/inventory/inventory.yml",
 }
 
@@ -60,9 +58,7 @@ def instance_file_manager():
     ],
 )
 def test_pydantic_manager_validate_correct_schemas(schema, schema_manager_pydantic):
-    assert (
-        schema in schema_manager_pydantic.schemas
-    ), f"Schema {schema} not found in {schema_manager_pydantic.schemas}"
+    assert schema in schema_manager_pydantic.schemas, f"Schema {schema} not found in {schema_manager_pydantic.schemas}"
     assert len(schema_manager_pydantic.schemas) == 5, "There should be 5 schemas."
 
 
@@ -83,9 +79,7 @@ def test_pydantic_manager_validate_correct_files(file, instance_file_manager):
     paths = [f"{f.full_path}/{f.filename}" for f in instance_file_manager.instances]
     assert file in paths, f"File {file} not found in {paths}"
     # 6 includes the `inventory.yml` for now.
-    assert (
-        len(instance_file_manager.instances) == 6
-    ), "There should be 6 variable files found."
+    assert len(instance_file_manager.instances) == 6, "There should be 6 variable files found."
 
 
 @mock.patch("schema_enforcer.config.load")
@@ -244,9 +238,7 @@ def test_pydantic_manager_ansible_show_checks_cli(_load):
     "pydantic_validators": [
         "pydantic_validators.models:manager1",
     ],
-    "data_file_search_directories": [
-        f"{FIXTURE_DIR}/test_validators_pydantic/inventory_fail"
-    ],
+    "data_file_search_directories": [f"{FIXTURE_DIR}/test_validators_pydantic/inventory_fail"],
     "ansible_inventory": f"{FIXTURE_DIR}/test_validators_pydantic/inventory_fail/inventory.yml",
 }
 
@@ -311,3 +303,25 @@ def test_pydantic_manager_ansible_show_pass_cli_failure(_load):
   Input is not a valid IPv6 address [type=ip_v6_address, input_value='2001:db8:16::yo', input_type=AnsibleUnicode]
 """
     assert expected == result.output, result.output
+
+
+@mock.patch("schema_enforcer.config.load")
+def test_pydantic_manager_ansible_invalid_validator_package(_load):
+    runner = CliRunner()
+    with mock.patch(
+        "schema_enforcer.config.SETTINGS",
+        Settings(
+            **{
+                "pydantic_validators": [
+                    "does_not_exist.models:manager1",
+                ],
+            }
+        ),
+    ):
+        result = runner.invoke(cli.validate)
+    _load.assert_called_once()
+    assert result.exit_code == 1
+    expected = """Unable to load the validator does_not_exist.models:manager1, the module (does_not_exist.models) does not exist.
+\x1b[31m  ERROR |\x1b[0m No schemas were loaded
+"""
+    assert expected == result.output, result.output