Added a trace property to the traceable interface classes

pynetbox/core/endpoint.py

@@ -21,7 +21,36 @@
 
 def response_loader(req, return_obj, endpoint):
     if isinstance(req, list):
-        return [return_obj(i, endpoint.api, endpoint) for i in req]
+        # interface/cable traces are lists of lists
+        if req and isinstance(req[0], list) and isinstance(return_obj, dict):
+            # we will have to build the response piecewise since the items contained
+            # within it are of varying types
+            ret = []
+            for i in req:
+                this_sub_ret = []
+                for ii in i:
+                    # the individual items in a trace are comprised of [<interface/
+                    # frontport/rearport>, <cable>, <interface/frontport/rearport>].
+                    # The last trace can consist of [<interface/frontport/rearport>,
+                    # None, None] if the last hop is not actually connected to anything
+                    if ii:
+                        this_sub_ret.append(
+                            next(
+                                (
+                                    return_obj_class(ii, endpoint.api, endpoint)
+                                    for (return_obj_uri, return_obj_class) in return_obj.items()
+                                    if return_obj_uri in ii["url"]
+                                )
+                            )
+                        )
+                    else:
+                        # the last trace can consist of [cable_a, None, None] if there is no
+                        this_sub_ret.append(None)
+
+                ret.append(this_sub_ret)
+            return ret
+        else:
+            return [return_obj(i, endpoint.api, endpoint) for i in req]
     return return_obj(req, endpoint.api, endpoint)
 
 

pynetbox/models/dcim.py

@@ -84,6 +84,33 @@ class Interfaces(Record):
     interface_connection = InterfaceConnection
     connected_endpoint = ConnectedEndpoint
 
+    @property
+    def trace(self):
+        """ Represents the ``trace`` detail endpoint.
+
+        Returns a DetailEndpoint object that is the interface for
+        viewing response from the trace endpoint.
+
+        :returns: :py:class:`.DetailEndpoint`
+
+        :Examples:
+
+        >>> interface = nb.dcim.interfaces.get(123)
+        >>> interface.trace.list()
+        {"get_facts": {"interface_list": ["ge-0/0/0"]}}
+
+        """
+        return RODetailEndpoint(
+            self,
+            "trace",
+            custom_return={
+                "dcim/cables": Cables,
+                "dcim/interfaces": Interfaces,
+                "dcim/front-ports": FrontPorts,
+                "dcim/rear-ports": RearPorts,
+            },
+        )
+
 
 class RackReservations(Record):
     def __str__(self):
@@ -99,6 +126,14 @@ class RUs(Record):
     device = Devices
 
 
+class FrontPorts(Record):
+    device = Devices
+
+
+class RearPorts(Record):
+    device = Devices
+
+
 class Racks(Record):
     @property
     def units(self):