Merge pull request #57 from jvanderaa/jv_fqdn

Add DNS Based OnBoarding

Author: dgarros

README.md

@@ -46,18 +46,24 @@ The plugin behavior can be controlled with the following list of settings
 - `create_platform_if_missing` boolean (default True), If True, a new platform object will be created if the platform discovered by netmiko do not already exist and is in the list of supported platforms (`cisco_ios`, `cisco_nxos`, `arista_eos`, `juniper_junos`, `cisco_xr`)
 - `create_device_type_if_missing` boolean (default True), If True, a new device type object will be created if the model discovered by Napalm do not match an existing device type.
 - `create_manufacturer_if_missing` boolean (default True), If True, a new manufacturer object will be created if the manufacturer discovered by Napalm is do not match an existing manufacturer, this option is only valid if `create_device_type_if_missing` is True as well.
-- `create_device_role_if_missing` boolean (default True), If True, a new device role object will be created if the device role provided was not provided as part of the onboarding and if the `default_device_role` do not already exist. 
+- `create_device_role_if_missing` boolean (default True), If True, a new device role object will be created if the device role provided was not provided as part of the onboarding and if the `default_device_role` do not already exist.
+- `create_management_interface_if_missing` boolean (default True), If True, add management interface and IP address to the device. If False no management interfaces will be created, nor will the IP address be added to NetBox, while the device will still get added.
 - `default_device_status` string (default "active"), status assigned to a new device by default (must be lowercase).
 - `default_device_role` string (default "network")
 - `default_device_role_color` string (default FF0000), color assigned to the device role if it needs to be created.
 - `default_management_interface` string (default "PLACEHOLDER"), name of the management interface that will be created, if one can't be identified on the device.
 - `default_management_prefix_length` integer ( default 0), length of the prefix that will be used for the management IP address, if the IP can't be found.
 
 ## Usage
+
 ### Preparation
 
-To work properly the plugin needs to know the Site, Platform, Device Type, Device Role of each device as well as its primary IP address.
-It's recommended to create these objects in NetBox ahead of time and to provide them when you want to start the onboarding process.
+To work properly the plugin needs to know the Site, Platform, Device Type, Device Role of each
+device as well as its primary IP address or DNS Name. It's recommended to create these objects in
+NetBox ahead of time and to provide them when you want to start the onboarding process.
+
+> For DNS Name Resolution to work, the instance of NetBox must be able to resolve the name of the
+> device to IP address.
 
 If `Platform`, `Device Type` and/or `Device Role` are not provided, the plugin will try to identify these information automatically and, based on the settings, it can create them in NetBox as needed.
 > If the Platform is provided, it must contains a valid Napalm driver available to the worker in Python

netbox_onboarding/__init__.py

@@ -38,6 +38,7 @@ class OnboardingConfig(PluginConfig):
         "default_management_interface": "PLACEHOLDER",
         "default_management_prefix_length": 0,
         "default_device_status": "active",
+        "create_management_interface_if_missing": True,
     }
     caching_config = {}
 

netbox_onboarding/choices.py

@@ -39,11 +39,13 @@ class OnboardingFailChoices(ChoiceSet):
     FAIL_CONNECT = "fail-connect"
     FAIL_EXECUTE = "fail-execute"
     FAIL_GENERAL = "fail-general"
+    FAIL_DNS = "fail-dns"
 
     CHOICES = (
         (FAIL_LOGIN, "fail-login"),
         (FAIL_CONFIG, "fail-config"),
         (FAIL_CONNECT, "fail-connect"),
         (FAIL_EXECUTE, "fail-execute"),
         (FAIL_GENERAL, "fail-general"),
+        (FAIL_DNS, "fail-dns"),
     )

netbox_onboarding/forms.py

@@ -29,7 +29,9 @@
 class OnboardingTaskForm(BootstrapMixin, forms.ModelForm):
     """Form for creating a new OnboardingTask instance."""
 
-    ip_address = forms.CharField(required=True, label="IP address", help_text="IP address of the device to onboard")
+    ip_address = forms.CharField(
+        required=True, label="IP address", help_text="IP Address/DNS Name of the device to onboard"
+    )
 
     site = forms.ModelChoiceField(required=True, queryset=Site.objects.all(), to_field_name="slug")
 

netbox_onboarding/onboard.py

@@ -18,6 +18,8 @@
 
 from napalm import get_network_driver
 from napalm.base.exceptions import ConnectionException, CommandErrorException
+import netaddr
+from netaddr.core import AddrFormatError
 
 from django.conf import settings
 from django.utils.text import slugify
@@ -48,6 +50,7 @@ class OnboardException(Exception):
         "fail-connect",  # device is unreachable at IP:PORT
         "fail-execute",  # unable to execute device/API command
         "fail-login",  # bad username/password
+        "fail-dns",  # failed to get IP address from name resolution
         "fail-general",  # other error
     )
 
@@ -198,6 +201,46 @@ def get_platform_object_from_netbox(platform_slug):
 
         return platform
 
+    def check_ip(self):
+        """Method to check if the IP address form field was an IP address.
+
+        If it is a DNS name, attempt to resolve the DNS address and assign the IP address to the
+        name.
+
+        Returns:
+            (bool): True if the IP address is an IP address, or a DNS entry was found and
+                    reassignment of the ot.ip_address was done.
+                    False if unable to find a device IP (error)
+
+        Raises:
+          OnboardException("fail-general"):
+            When a prefix was entered for an IP address
+          OnboardException("fail-dns"):
+            When a Name lookup via DNS fails to resolve an IP address
+        """
+        try:
+            # Assign checked_ip to None for error handling
+            # If successful, this is an IP address and can pass
+            checked_ip = netaddr.IPAddress(self.ot.ip_address)
+            return True
+        # Catch when someone has put in a prefix address, raise an exception
+        except ValueError:
+            raise OnboardException(
+                reason="fail-general", message=f"ERROR appears a prefix was entered: {self.ot.ip_address}"
+            )
+        # An AddrFormatError exception means that there is not an IP address in the field, and should continue on
+        except AddrFormatError:
+            try:
+                # Do a lookup of name to get the IP address to connect to
+                checked_ip = socket.gethostbyname(self.ot.ip_address)
+                self.ot.ip_address = checked_ip
+                return True
+            except socket.gaierror:
+                # DNS Lookup has failed, Raise an exception for unable to complete DNS lookup
+                raise OnboardException(
+                    reason="fail-dns", message=f"ERROR failed to complete DNS lookup: {self.ot.ip_address}"
+                )
+
     def get_required_info(
         self,
         default_mgmt_if=PLUGIN_SETTINGS["default_management_interface"],
@@ -215,6 +258,8 @@ def get_required_info(
           OnboardException('fail-general'):
             Any other unexpected device comms failure.
         """
+        # Check to see if the IP address entered was an IP address or a DNS entry, get the IP address
+        self.check_ip()
         self.check_reachability()
         mgmt_ipaddr = self.ot.ip_address
 
@@ -474,5 +519,6 @@ def ensure_device(self):
         self.ensure_device_type()
         self.ensure_device_role()
         self.ensure_device_instance()
-        self.ensure_interface()
-        self.ensure_primary_ip()
+        if PLUGIN_SETTINGS["create_management_interface_if_missing"]:
+            self.ensure_interface()
+            self.ensure_primary_ip()

netbox_onboarding/tests/test_onboard.py

@@ -11,6 +11,8 @@
 See the License for the specific language governing permissions and
 limitations under the License.
 """
+from socket import gaierror
+from unittest import mock
 from django.test import TestCase
 from django.utils.text import slugify
 
@@ -40,6 +42,16 @@ def setUp(self):
         self.onboarding_task3 = OnboardingTask.objects.create(
             ip_address="192.168.1.2", site=self.site1, role=self.device_role1, platform=self.platform1
         )
+        self.onboarding_task4 = OnboardingTask.objects.create(
+            ip_address="ntc123.local", site=self.site1, role=self.device_role1, platform=self.platform1
+        )
+
+        self.onboarding_task5 = OnboardingTask.objects.create(
+            ip_address="bad.local", site=self.site1, role=self.device_role1, platform=self.platform1
+        )
+        self.onboarding_task7 = OnboardingTask.objects.create(
+            ip_address="192.0.2.1/32", site=self.site1, role=self.device_role1, platform=self.platform1
+        )
 
         self.ndk1 = NetdevKeeper(self.onboarding_task1)
         self.ndk1.hostname = "device1"
@@ -172,7 +184,7 @@ def test_ensure_interface_exist(self):
         self.assertEqual(nbk.interface, intf)
 
     def test_ensure_primary_ip_not_exist(self):
-        """Verify ensure_primary_ip function when the Ip address do not already exist."""
+        """Verify ensure_primary_ip function when the IP address do not already exist."""
         nbk = NetboxKeeper(self.ndk2)
         nbk.device_type = self.device_type1
         nbk.netdev.ot = self.onboarding_task3
@@ -182,3 +194,38 @@ def test_ensure_primary_ip_not_exist(self):
         nbk.ensure_primary_ip()
         self.assertIsInstance(nbk.primary_ip, IPAddress)
         self.assertEqual(nbk.primary_ip.interface, nbk.interface)
+
+    @mock.patch("netbox_onboarding.onboard.socket.gethostbyname")
+    def test_check_ip(self, mock_get_hostbyname):
+        """Check DNS to IP address."""
+        # Look up response value
+        mock_get_hostbyname.return_value = "192.0.2.1"
+
+        # Create a Device Keeper object of the device
+        ndk4 = NetdevKeeper(self.onboarding_task4)
+
+        # Check that the IP address is returned
+        self.assertTrue(ndk4.check_ip())
+
+        # Run the check to change the IP address
+        self.assertEqual(ndk4.ot.ip_address, "192.0.2.1")
+
+    @mock.patch("netbox_onboarding.onboard.socket.gethostbyname")
+    def test_failed_check_ip(self, mock_get_hostbyname):
+        """Check DNS to IP address failing."""
+        # Look up a failed response
+        mock_get_hostbyname.side_effect = gaierror(8)
+        ndk5 = NetdevKeeper(self.onboarding_task5)
+        ndk7 = NetdevKeeper(self.onboarding_task7)
+
+        # Check for bad.local raising an exception
+        with self.assertRaises(OnboardException) as exc_info:
+            ndk5.check_ip()
+            self.assertEqual(exc_info.exception.message, "ERROR failed to complete DNS lookup: bad.local")
+            self.assertEqual(exc_info.exception.reason, "fail-dns")
+
+        # Check for exception with prefix address entered
+        with self.assertRaises(OnboardException) as exc_info:
+            ndk7.check_ip()
+            self.assertEqual(exc_info.exception.reason, "fail-prefix")
+            self.assertEqual(exc_info.exception.message, "ERROR appears a prefix was entered: 192.0.2.1/32")