US2765 ACI scanning: Added spine switches and pnics fetching functionality

Change-Id: Ibc483f5160a6a65f4b2066fcdb1ca09db798251c
Signed-off-by: Yaron Yogev <yaronyogev@gmail.com>

diff --git a/app/discover/fetchers/aci/aci_fetch_leaf_to_spine_pnics.py b/app/discover/fetchers/aci/aci_fetch_leaf_to_spine_pnics.py
new file mode 100644 (file)
index 0000000..48cf243
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+++ b/app/discover/fetchers/aci/aci_fetch_leaf_to_spine_pnics.py
@@ -0,0 +1,141 @@
+###############################################################################
+# Copyright (c) 2017 Koren Lev (Cisco Systems), Yaron Yogev (Cisco Systems)   #
+# and others                                                                  #
+#                                                                             #
+# All rights reserved. This program and the accompanying materials            #
+# are made available under the terms of the Apache License, Version 2.0       #
+# which accompanies this distribution, and is available at                    #
+# http://www.apache.org/licenses/LICENSE-2.0                                  #
+###############################################################################
+import re
+
+from discover.fetchers.aci.aci_access import AciAccess, aci_config_required
+from utils.inventory_mgr import InventoryMgr
+from utils.util import decode_aci_dn, encode_aci_dn, get_object_path_part
+
+
+# Fetches and adds to database:
+# 1. ACI Switches with role "spine"
+#
+# Returns:
+# 1. ACI Switch uplink pnics that belong to the "leaf" switch
+# 2. ACI Switch downlink pnics that belong to "spine" switches mentioned above
+# and are connected to the "leaf" switch
+class AciFetchLeafToSpinePnics(AciAccess):
+
+    def __init__(self):
+        super().__init__()
+        self.inv = InventoryMgr()
+
+    def fetch_switches_by_role(self, role_name):
+        query_filter = "eq(fabricNode.role, \"{}\")".format(role_name)
+        switches = self.fetch_objects_by_class("fabricNode",
+                                               {"query-target-filter": query_filter})
+        return [switch["attributes"] for switch in switches]
+
+    def fetch_adjacent_connections(self, device_id):
+        dn = "/".join((device_id, "sys"))
+
+        response = self.fetch_mo_data(dn,
+                                      {"query-target": "subtree",
+                                       "target-subtree-class": "lldpAdjEp"})
+
+        connections = self.get_objects_by_field_names(response,
+                                                      "lldpAdjEp", "attributes")
+        return connections
+
+    # Returns:
+    # List of:
+    # 1. Switches with role "spine"
+    # 2. Downlink pnic id for spine switch
+    # 3. Uplink pnic id for leaf switch
+    def fetch_spines_and_pnics_by_leaf_id(self, leaf_id):
+        spine_switches = self.fetch_switches_by_role("spine")
+        adjacent_devices = self.fetch_adjacent_connections(leaf_id)
+        spines = []
+        for spine in spine_switches:
+            # Check if spine switch is connected to current leaf switch
+            connection = next((d for d in adjacent_devices
+                               if spine["name"] == d["sysName"]),
+                              None)
+            if connection:
+                try:
+                    # Extract pnics from adjacency data
+                    uplink_pnic = re.match(".*\[(.+?)\].*", connection["dn"]).group(1)
+                    downlink_pnic = re.match(".*\[(.+?)\].*", connection["portDesc"]).group(1)
+                    spines.append({
+                        "device": spine,
+                        "downlink_pnic": downlink_pnic,
+                        "uplink_pnic": uplink_pnic
+                    })
+                except AttributeError:
+                    continue  # TODO: probably raise an exception
+
+        return spines
+
+    @aci_config_required(default=[])
+    def get(self, db_leaf_pnic_id):
+        environment = self.get_env()
+        pnic = self.inv.get_by_id(environment=environment, item_id=db_leaf_pnic_id)
+
+        # Decode aci leaf switch id from db format
+        aci_leaf_pnic_id = decode_aci_dn(db_leaf_pnic_id)
+        aci_leaf_id = re.match("switch-(.+?)-leaf", aci_leaf_pnic_id).group(1)
+
+        # Fetch all leaf-to-spine connectivity data
+        spines_with_pnics = self.fetch_spines_and_pnics_by_leaf_id(aci_leaf_id)
+        pnics = []
+        for spine_with_pnic in spines_with_pnics:
+            spine = spine_with_pnic["device"]
+            downlink_pnic_id = spine_with_pnic["downlink_pnic"]
+            uplink_pnic_id = spine_with_pnic["uplink_pnic"]
+
+            # Add spine switch to db if it's not there yet
+            spine_id_match = re.match("topology/(.+)", spine["dn"])
+            if not spine_id_match:
+                raise ValueError("Failed to fetch spine switch id from switch dn: {}"
+                                 .format(spine["dn"]))
+
+            aci_spine_id = spine_id_match.group(1)
+            db_spine_id = "-".join(("switch", encode_aci_dn(aci_spine_id), spine["role"]))
+            if not self.inv.get_by_id(environment, db_spine_id):
+                spine_json = {
+                    "id": db_spine_id,
+                    "type": "switch",
+                    "host": db_spine_id,
+                    "aci_document": spine
+                }
+                # Region name is the same as region id
+                region_id = get_object_path_part(pnic["name_path"], "Regions")
+                region = self.inv.get_by_id(environment, region_id)
+                self.inv.save_inventory_object(o=spine_json, parent=region, environment=environment)
+
+            # Add downlink and uplink pnics to results list,
+            # including their mutual connection data
+            # (see "connected_to" field).
+            db_downlink_pnic_id = "-".join((db_spine_id,
+                                            encode_aci_dn(downlink_pnic_id)))
+            db_uplink_pnic_id = "-".join((pnic["host"],  # host == switch
+                                          encode_aci_dn(uplink_pnic_id)))
+
+            downlink_pnic_json = {
+                "id": db_downlink_pnic_id,
+                "type": "pnic",
+                "pnic_type": "switch",
+                "host": db_spine_id,
+                "connected_to": db_uplink_pnic_id,
+                "aci_document": {}  # TODO: what can we add here?
+            }
+
+            uplink_pnic_json = {
+                "id": db_uplink_pnic_id,
+                "type": "pnic",
+                "pnic_type": "switch",
+                "host": pnic["host"],
+                "connected_to": db_downlink_pnic_id,
+                "aci_document": {}  # TODO: what can we add here?
+            }
+
+            pnics.extend([downlink_pnic_json, uplink_pnic_json])
+
+        return pnics