Merge pull request #2613 from levinine/add_nat_gateway_id_to_route_and_describe_route_tables

Add nat_gateway_id to route and describe_route_tables

moto/ec2/models.py

@@ -3306,6 +3306,7 @@ class Route(object):
         local=False,
         gateway=None,
         instance=None,
+        nat_gateway=None,
         interface=None,
         vpc_pcx=None,
     ):
@@ -3315,6 +3316,7 @@ class Route(object):
         self.local = local
         self.gateway = gateway
         self.instance = instance
+        self.nat_gateway = nat_gateway
         self.interface = interface
         self.vpc_pcx = vpc_pcx
 
@@ -3327,6 +3329,7 @@ class Route(object):
         gateway_id = properties.get("GatewayId")
         instance_id = properties.get("InstanceId")
         interface_id = properties.get("NetworkInterfaceId")
+        nat_gateway_id = properties.get("NatGatewayId")
         pcx_id = properties.get("VpcPeeringConnectionId")
 
         route_table_id = properties["RouteTableId"]
@@ -3336,6 +3339,7 @@ class Route(object):
             destination_cidr_block=properties.get("DestinationCidrBlock"),
             gateway_id=gateway_id,
             instance_id=instance_id,
+            nat_gateway_id=nat_gateway_id,
             interface_id=interface_id,
             vpc_peering_connection_id=pcx_id,
         )
@@ -3353,6 +3357,7 @@ class RouteBackend(object):
         local=False,
         gateway_id=None,
         instance_id=None,
+        nat_gateway_id=None,
         interface_id=None,
         vpc_peering_connection_id=None,
     ):
@@ -3373,12 +3378,17 @@ class RouteBackend(object):
         except ValueError:
             raise InvalidDestinationCIDRBlockParameterError(destination_cidr_block)
 
+        nat_gateway = None
+        if nat_gateway_id is not None:
+            nat_gateway = self.nat_gateways.get(nat_gateway_id)
+
         route = Route(
             route_table,
             destination_cidr_block,
             local=local,
             gateway=gateway,
             instance=self.get_instance(instance_id) if instance_id else None,
+            nat_gateway=nat_gateway,
             interface=None,
             vpc_pcx=self.get_vpc_peering_connection(vpc_peering_connection_id)
             if vpc_peering_connection_id

moto/ec2/responses/route_tables.py

@@ -18,6 +18,7 @@ class RouteTables(BaseResponse):
         destination_cidr_block = self._get_param("DestinationCidrBlock")
         gateway_id = self._get_param("GatewayId")
         instance_id = self._get_param("InstanceId")
+        nat_gateway_id = self._get_param("NatGatewayId")
         interface_id = self._get_param("NetworkInterfaceId")
         pcx_id = self._get_param("VpcPeeringConnectionId")
 
@@ -26,6 +27,7 @@ class RouteTables(BaseResponse):
             destination_cidr_block,
             gateway_id=gateway_id,
             instance_id=instance_id,
+            nat_gateway_id=nat_gateway_id,
             interface_id=interface_id,
             vpc_peering_connection_id=pcx_id,
         )
@@ -173,6 +175,10 @@ DESCRIBE_ROUTE_TABLES_RESPONSE = """
                   <origin>CreateRoute</origin>
                   <state>blackhole</state>
                 {% endif %}
+                {% if route.nat_gateway %}
+                  <natGatewayId>{{ route.nat_gateway.id }}</natGatewayId>
+                  <state>active</state>
+                {% endif %}
               </item>
             {% endfor %}
           </routeSet>

tests/test_ec2/test_route_tables.py

@@ -581,3 +581,40 @@ def test_create_route_with_invalid_destination_cidr_block_parameter():
             destination_cidr_block
         )
     )
+
+
+@mock_ec2
+def test_describe_route_tables_with_nat_gateway():
+    ec2 = boto3.client("ec2", region_name="us-west-1")
+    vpc_id = ec2.create_vpc(CidrBlock="192.168.0.0/23")["Vpc"]["VpcId"]
+    igw_id = ec2.create_internet_gateway()["InternetGateway"]["InternetGatewayId"]
+    ec2.attach_internet_gateway(VpcId=vpc_id, InternetGatewayId=igw_id)
+    az = ec2.describe_availability_zones()["AvailabilityZones"][0]["ZoneName"]
+    sn_id = ec2.create_subnet(
+        AvailabilityZone=az, CidrBlock="192.168.0.0/24", VpcId=vpc_id
+    )["Subnet"]["SubnetId"]
+    route_table_id = ec2.create_route_table(VpcId=vpc_id)["RouteTable"]["RouteTableId"]
+    ec2.associate_route_table(SubnetId=sn_id, RouteTableId=route_table_id)
+    alloc_id = ec2.allocate_address(Domain="vpc")["AllocationId"]
+    nat_gw_id = ec2.create_nat_gateway(SubnetId=sn_id, AllocationId=alloc_id)[
+        "NatGateway"
+    ]["NatGatewayId"]
+    ec2.create_route(
+        DestinationCidrBlock="0.0.0.0/0",
+        NatGatewayId=nat_gw_id,
+        RouteTableId=route_table_id,
+    )
+
+    route_table = ec2.describe_route_tables(
+        Filters=[{"Name": "route-table-id", "Values": [route_table_id]}]
+    )["RouteTables"][0]
+    nat_gw_routes = [
+        route
+        for route in route_table["Routes"]
+        if route["DestinationCidrBlock"] == "0.0.0.0/0"
+    ]
+
+    nat_gw_routes.should.have.length_of(1)
+    nat_gw_routes[0]["DestinationCidrBlock"].should.equal("0.0.0.0/0")
+    nat_gw_routes[0]["NatGatewayId"].should.equal(nat_gw_id)
+    nat_gw_routes[0]["State"].should.equal("active")