Dynamic Remediation Functions and Mapping to override default hier_config

docs/user/app_feature_remediation.md

@@ -26,6 +26,7 @@ The type of remediation to be performed in a particular platform is defined by n
 Network device operating systems (Nautobot Platforms) can consume two different types of remediation, namely:
 
 - **HIERCONFIG remediation (CLI - hierarchical)**
+- **Dynamic HIERCONFIG remediation**
 - **Custom Remediation**
 
 ![Remediation Platform Settings](../images/remediation_settings_per_platform.png)
@@ -48,6 +49,33 @@ Default Hier config options can be used or customized on a per platform basis, a
 For additional information on how to customize Hier Config options, please refer to the Hierarchical Configuration development guide:
 https://netdevops.io/hier_config/advanced-topics/
 
+### Dynamic Hier Config Remediation Type
+
+The Dynamic Hier Config remediation option is an additional lever to customize the default Hier Config remediation config without the need to rewrite the entire Hier Config flow in a custom remediation function.  Dynamic remeditaion takes the form of modules imported from a Git repository.  Specifically within the root folder of the repository, there should be a folder called `hier_config_dynamic_remediations`, and within that folder should be an `__init__.py` and any dynamic remediations that have been created.  The folder structure for the Git repository should be similiar to the following:
+
+```shell
+├── hier_config_dynamic_remediations
+│   ├── __init__.py // necessary to discover the functions dynamically
+│   ├── file_1.py
+│   ├── file_2.py
+│   └── file_3.py
+```
+
+Each dynamic remediation file should have a function called `remediation` that accepts a `remediation_config` argument.  The `remediation_config` argument is the `hier_config.root.HConfig` object that is created when the difference between the backup and intended config is generated by the **Perform Configuration Compliance** job.  Any changes should be made directly to that arugment.
+
+For example, the following code would remove any sequence numbers from a Cisco IOS ACL config block:
+
+```python
+def remediation(remediation_config):
+    lineage = remediation_config.get_child("startswith", "ip access-list")
+    for line in lineage.all_children():
+        line_items = line.text.split()
+        index = 1 if line.text.startswith("no") else 0
+        line_items.remove(line_items[index])
+        lineage.del_child_by_text(line.text)
+        lineage.add_child(" ".join(line_items))
+```
+
 ### Custom Config Remediation Type
 
 When a Network Operating System delivers configuration data in a format that is not CLI/Hierarchical, we can still perform remediation by using the Custom Remediation options. Custom Remediation is defined within a Python function that takes as input a Configuration Compliance object and returns a Remediation Field.

nautobot_golden_config/choices.py

@@ -20,10 +20,12 @@ class RemediationTypeChoice(ChoiceSet):
     """Choiceset used by RemediationSetting."""
 
     TYPE_HIERCONFIG = "hierconfig"
+    TYPE_DYNAMIC_HIERCONFIG = "dynamic_hierconfig"
     TYPE_CUSTOM = "custom_remediation"
 
     CHOICES = (
         (TYPE_HIERCONFIG, "HIERCONFIG"),
+        (TYPE_DYNAMIC_HIERCONFIG, "DYNAMIC_HIERCONFIG"),
         (TYPE_CUSTOM, "CUSTOM_REMEDIATION"),
     )
 

nautobot_golden_config/datasources.py

@@ -36,6 +36,32 @@ def refresh_git_backup(repository_record, job_result, delete=False):  # pylint:
     )
 
 
+def refresh_git_gc_dynamic_remediations(repository_record, job_result, delete=False):  # pylint: disable=unused-argument
+    """Callback for gitrepository updates on Hier Config Dynamic Remediation repo."""
+    job_result.log(
+        "Successfully Pulled git repo test",
+        level_choice=LogLevelChoices.LOG_DEBUG,
+    )
+
+    dynamic_remediation_path = os.path.join(repository_record.filesystem_path, "hier_config_dynamic_remediations")
+    if not os.path.isdir(dynamic_remediation_path):
+        job_result.log(
+            f"Skipping sync for {dynamic_remediation_path} because directory doesn't exist.",
+            level_choice=LogLevelChoices.LOG_INFO,
+        )
+        return
+
+    for root, _, files in os.walk(dynamic_remediation_path):
+        for file_name in files:
+            if not file_name.endswith(".py") or "__init__" in file_name:
+                continue
+            # file_info.append({"root": root, "file_name": file_name})
+            job_result.log(
+                f"File {file_name} found in repository.",
+                level_choice=LogLevelChoices.LOG_INFO
+            )
+
+
 def refresh_git_gc_properties(repository_record, job_result, delete=False):  # pylint: disable=unused-argument
     """Callback for gitrepository updates on Git Configuration repo.
 
@@ -244,6 +270,18 @@ def update_git_gc_properties(golden_config_path, job_result, gc_config_item):  #
             ),
         )
     )
+if ENABLE_COMPLIANCE:
+    datasource_contents.append(
+        (
+            "extras.gitrepository",
+            DatasourceContent(
+                name="Hier Config Dynamic Remediations",
+                content_identifier="nautobot_golden_config.hierconfigdynamicremediations",
+                icon="mdi-file-code",
+                callback=refresh_git_gc_dynamic_remediations,
+            ),
+        )
+    )
 
 datasource_contents.append(
     (

nautobot_golden_config/models.py

@@ -2,6 +2,8 @@
 
 import json
 import logging
+import pkgutil
+import sys
 
 from deepdiff import DeepDiff
 from django.core.exceptions import ValidationError
@@ -11,7 +13,7 @@
 from nautobot.core.models.generics import PrimaryModel
 from nautobot.core.models.utils import serialize_object, serialize_object_v2
 from nautobot.dcim.models import Device
-from nautobot.extras.models import ObjectChange
+from nautobot.extras.models import ObjectChange, GitRepository
 from nautobot.extras.models.statuses import StatusField
 from nautobot.extras.utils import extras_features
 from netutils.config.compliance import feature_compliance
@@ -198,7 +200,19 @@ def _get_hierconfig_remediation(obj):
 
     host.load_generated_config(obj.intended)
     host.load_running_config(obj.actual)
-    host.remediation_config()
+    rem = host.remediation_config()
+
+    if remediation_setting_obj.remediation_type == RemediationTypeChoice.TYPE_DYNAMIC_HIERCONFIG:
+        repos = GitRepository.objects.filter(provided_contents__contains="nautobot_golden_config.hierconfigdynamicremediations")
+        for repo in repos:
+            for importer, discovered_module_name, _ in pkgutil.iter_modules(
+                [f"{repo.filesystem_path}/hier_config_dynamic_remediations"]
+            ):
+                if "__init__" in discovered_module_name:
+                    continue
+                module = importer.find_module(discovered_module_name).load_module(discovered_module_name)
+                module.remediation(rem)
+
     remediation_config = host.remediation_config_filtered_text(include_tags={}, exclude_tags={})
 
     return remediation_config
@@ -210,6 +224,7 @@ def _get_hierconfig_remediation(obj):
     ComplianceRuleConfigTypeChoice.TYPE_JSON: _get_json_compliance,
     ComplianceRuleConfigTypeChoice.TYPE_XML: _get_xml_compliance,
     RemediationTypeChoice.TYPE_HIERCONFIG: _get_hierconfig_remediation,
+    RemediationTypeChoice.TYPE_DYNAMIC_HIERCONFIG: _get_hierconfig_remediation,
 }
 # The below conditionally add the custom provided compliance type
 for custom_function, custom_type in CUSTOM_FUNCTIONS.items():