Add equipments and topolgies endpoints

- add POST, PUT, DELETE on equipments
- add POST, PUT, GET, DELETE on topogies
- path-computation request body can now have equipment id and/or
topology id instead of full data
- activate embedded https of Flask while waiting for real trusted
certificate
- update readme
- add request payload samples in yang directory
- equipment data are encrypted with Fernet

Signed-off-by: manuedelf <59697943+edelfour@users.noreply.github.com>

gnpy/api/service/topology_service.py

@@ -0,0 +1,62 @@
+# coding: utf-
+import json
+import os
+import uuid
+
+from gnpy.api.exception.topology_error import TopologyError
+from gnpy.api.service import config_service
+
+
+def save_topology(topology):
+    """
+    Save topology to file.
+    @param topology: json content
+    @return: a UUID identifier to identify the topology
+    """
+    topology_identifier = str(uuid.uuid4())
+    # TODO: validate json content
+    _write_topology(topology, topology_identifier)
+    return topology_identifier
+
+
+def update_topology(topology, topology_identifier):
+    """
+    Update topology with identifier topology_identifier.
+    @param topology_identifier: the identifier of the topology to be updated
+    @param topology: json content
+    @return: a UUID identifier to identify the topology
+    """
+    # TODO: validate json content
+    _write_topology(topology, topology_identifier)
+    return topology_identifier
+
+
+def _write_topology(topology, topology_identifier):
+    topology_dir = config_service.get_topology_dir()
+    with(open(os.path.join(topology_dir, '.'.join([topology_identifier, 'json'])), 'w')) as file:
+        json.dump(topology, file)
+
+
+def get_topology(topology_id: str) -> dict:
+    """
+    Get the topology with id topology_id
+    @param topology_id:
+    @return: the topology in json format
+    """
+    topology_dir = config_service.get_topology_dir()
+    topology_file = os.path.join(topology_dir, '.'.join([topology_id, 'json']))
+    if not os.path.exists(topology_file):
+        raise TopologyError('Topology with id {} does not exist '.format(topology_id))
+    with(open(topology_file, 'r')) as file:
+        return json.load(file)
+
+
+def delete_topology(topology_id: str):
+    """
+    Delete topology with id topology_id
+    @param topology_id:
+    """
+    topology_dir = config_service.get_topology_dir()
+    topology_file = os.path.join(topology_dir, '.'.join([topology_id, 'json']))
+    if os.path.exists(topology_file):
+        os.remove(topology_file)