Feature/reporting 307 msr vpn proxy endpoint

Adds /msr/vpn-proxy endpoint

inventory_provider/routes/msr.py

@@ -64,12 +64,19 @@ These endpoints are intended for use by MSR.
 
 .. autofunction:: inventory_provider.routes.msr.mdvpn
 
+
 /msr/services
 --------------------------------------------
 
 .. autofunction:: inventory_provider.routes.msr.get_system_correlation_services
 
 
+/msr/vpn-proxy
+--------------------------------------------
+
+.. autofunction:: inventory_provider.routes.msr.vpn-proxy
+
+
 helpers
 -------------------------------------
 
@@ -321,6 +328,34 @@ MDVPN_LIST_SCHEMA = {
     'items': {'$ref': '#/definitions/mdvpn_group'}
 }
 
+VPN_PROXY_LIST_SCHEMA = {
+    '$schema': 'http://json-schema.org/draft-07/schema#',
+    'definitions': {
+        'vpn_proxy_peering': {
+            'type': 'object',
+            'properties': {
+                'pop': {'type': 'string'},
+                'nren': {'type': 'string'},
+                'group': {'type': 'string'},
+                'v4': {'type': 'string'}
+            },
+            'additionalProperties': False
+        }
+    },
+    'type': 'array',
+    'items': {'$ref': '#/definitions/vpn_proxy_peering'}
+}
+
+DOMAIN_TO_POP_MAPPING = {
+    "mad.es": "Madrid",
+    "bra.sk": "Bratislava",
+    "vie.at": "Vienna",
+    "gen.ch": "Geneva",
+    "fra.de": "Frankfurt",
+    "pra.cz": "Prague",
+    "ams.nl": "Amsterdam"
+}
+
 
 @routes.after_request
 def after_request(resp):
@@ -1053,3 +1088,93 @@ def mdvpn():
             for pair in nren_asn_map]
         response = json.dumps(nren_details)
     return Response(response, mimetype='application/json')
+
+
+@routes.route('/vpn-proxy', methods=['GET', 'POST'])
+@common.require_accepts_json
+def vpn_proxy():
+    """
+        Handler for `/vpn-proxy`
+
+        This method returns a list of all L3VPN related VPN proxy peerings.
+
+        The response will be formatted according to the following schema:
+
+        .. asjson::
+           inventory_provider.routes.msr.VPN_PROXY_LIST_SCHEMA
+
+        :return:
+        """
+
+    def _is_relevant(item):
+        """
+        Determine if a given peering in the VPN-PROXY logical system is
+        relevant to this endpoint (whether it's related to L3VPN)
+        :param item: peering dict
+        :return: True if the peering is L3VPN relevant, False otherwise
+        """
+        desc = item.get("description")
+        if desc is None:
+            return False
+        return "L3VPN" in desc
+
+    def _look_up_city_from_hostname(hostname):
+        """
+        Get the city name for a peering from a partial hostname match.
+        This uses a hardcoded lookup table.
+        :param hostname: hostname for the peering
+        :return: city name if found, "Unknown" otherwise
+        """
+        for snippet in DOMAIN_TO_POP_MAPPING:
+            if snippet in hostname:
+                return DOMAIN_TO_POP_MAPPING[snippet]
+        return "Unknown"
+
+    def _extract_nren_from_description(desc, group):
+        """
+        Retrieve the relevant NREN from the peering description and group.
+        This approach is, by its nature, very fragile to any changes to
+        descriptions, and should be revisited when that happens.
+
+        :param desc: description of a VPN-Proxy peering
+        :param group: group of the same VPN-Proxy peering
+        :return: name of the NREN
+        """
+        if group == "PRACE":
+            # common trait: the NREN is the first word in the description
+            return desc.split(' ')[0]
+        else:
+            # only other group is XiFi, and only CESNet is relevant
+            return 'CESNet'
+
+    def _format_peerings(vpnproxy):
+        """
+        Generator that iterates through a list of peering dicts, yielding
+        appropriately reformatted peerings if they are relevant to L3VPN.
+        :param vpnproxy: list of peering dicts taken from current redis
+        :return: generator of reformated peerings
+        """
+        for peering in vpnproxy:
+            if _is_relevant(peering):
+                desc = peering["description"]
+                group = peering["group"]
+                hostname = peering["hostname"]
+                formatted_peering = {
+                    "pop": _look_up_city_from_hostname(hostname),
+                    "nren": _extract_nren_from_description(desc, group),
+                    "group": group,
+                    "v4": peering.get("address")
+                }
+                yield formatted_peering
+            else:
+                yield False
+
+    r = common.get_current_redis()
+    cache_key = 'classifier-cache:msr:vpn-proxy'
+    response = _ignore_cache_or_retrieve(request, cache_key, r)
+    if not response:
+        vpnproxy = json.loads(
+            r.get('juniper-peerings:logical-system:VPN-PROXY').decode('utf-8'))
+        peerings = list(filter(None, _format_peerings(vpnproxy)))
+        response = json.dumps(peerings)
+    return Response(response, mimetype='application/json')