Update disassociate fip API

1. Remove DELETE request body
2. Add API doc

Change-Id: I2b86826427bd6d464f4da4c003ef6624a6a354a8

api-ref/source/v1/instance_networks.inc

@@ -66,3 +66,24 @@ Request
 **Example request to Add (Associate) Floating IP to an instance:**
 
 .. literalinclude:: samples/instances/instance-associate-fip-req.json
+
+
+Remove (Disassociate) Floating IP
+=================================
+
+.. rest_method:: DELETE /v1/instances/{instance_uuid}/networks/floatingips/{fip_address}
+
+Removes, or disassociates, a floating IP address from an instance.
+
+Normal response codes: 204
+
+Error response codes: badRequest(400), unauthorized(401), forbidden(403),
+itemNotFound(404), conflict(409)
+
+Request
+-------
+
+.. rest_parameters:: parameters.yaml
+
+    - instance_uuid: instance_ident
+    - fip_address: address_path

api-ref/source/v1/parameters.yaml

@@ -9,6 +9,12 @@ openstack-request-id:
   type: string
 
 # variables in path
+address_path:
+  description: |
+    The floating IP address.
+  in: path
+  required: true
+  type: string
 api_version:
   in: path
   required: true

mogan/api/controllers/v1/instances.py

@@ -207,17 +207,18 @@ class FloatingIPController(InstanceControllerBase):
                 msg, status_code=http_client.BAD_REQUEST)
 
     @policy.authorize_wsgi("mogan:instance", "disassociate_floatingip")
-    @expose.expose(None, types.uuid, types.jsontype,
+    @expose.expose(None, types.uuid, wtypes.text,
                    status_code=http_client.NO_CONTENT)
-    def delete(self, instance_uuid, floatingip):
+    def delete(self, instance_uuid, address):
         """Dissociate floating_ip from an instance.
 
         :param instance_uuid: UUID of a instance.
         :param floatingip: The floating IP within the request body.
         """
-        validation.check_schema(floatingip, fip_schemas.remove_floating_ip)
-        address = floatingip['address']
-
+        if not netutils.is_valid_ipv4(address):
+            msg = "Invalid IP address %s" % address
+            raise wsme.exc.ClientSideError(
+                msg, status_code=http_client.BAD_REQUEST)
         # get the floating ip object
         try:
             floating_ip = self.network_api.get_floating_ip_by_address(

mogan/api/controllers/v1/schemas/floating_ips.py

@@ -26,13 +26,3 @@ add_floating_ip = {
     'required': ['address'],
     'additionalProperties': False
 }
-
-
-remove_floating_ip = {
-    'type': 'object',
-    'properties': {
-        'address': parameter_types.ip_address,
-    },
-    'required': ['address'],
-    'additionalProperties': False
-}