def test_should_not_use_existing_igw_attached_to_different_vpc_in_stack(
self):
# Setup
stack = Stack()
stack.Resources["MyVPC"] = vpc = VPC()
stack.Resources["OtherVPC"] = other_vpc = VPC()
stack.Resources["MyGateway"] = igw = InternetGateway()
stack.Resources[
"MyGatewayAttachment"] = attachment = VPCGatewayAttachment(
Properties=dict(
InternetGatewayId=Ref(igw),
VpcId=Ref(other_vpc),
))
# Exercise
vpc.ensure_internet_gateway_exists(stack)
# Verify
self._verify_vpc_has_valid_internet_gateway(vpc)
self._verify_resource_is_in_stack(vpc.internet_gateway, stack)
self._verify_resource_is_in_stack(vpc.internet_gateway_attachment,
stack)
# Verify existing Internet Gateway attachment is not used
assert igw is not vpc.internet_gateway
self._verify_resource_is_in_stack(igw, stack)
assert attachment is not vpc.internet_gateway_attachment
self._verify_resource_is_in_stack(attachment, stack)
def test_should_do_nothing_when_called_a_second_time(self):
# Setup: Create stack
stack = Stack()
stack.Resources["MyVPC"] = vpc = VPC()
# Setup: Call once
vpc.ensure_internet_gateway_exists(stack)
original_igw = vpc.internet_gateway
original_attachment = vpc.internet_gateway_attachment
# Exercise
vpc.ensure_internet_gateway_exists(stack)
# Verify
self._verify_vpc_has_valid_internet_gateway(vpc)
self._verify_resource_is_in_stack(vpc.internet_gateway,
stack,
unique=True)
self._verify_resource_is_in_stack(vpc.internet_gateway_attachment,
stack,
unique=True)
# Verify Internet Gateway hasn't changed
assert vpc.internet_gateway is original_igw
assert vpc.internet_gateway_attachment is original_attachment
def test_should_use_existing_igw_attached_to_vpc_in_stack(self):
# Setup
stack = Stack()
stack.Resources["MyVPC"] = vpc = VPC()
stack.Resources["MyGateway"] = igw = InternetGateway()
stack.Resources[
"MyGatewayAttachment"] = attachment = VPCGatewayAttachment(
Properties=dict(
InternetGatewayId=Ref(igw),
VpcId=Ref(vpc),
))
# Exercise
vpc.ensure_internet_gateway_exists(stack)
# Verify
self._verify_vpc_has_valid_internet_gateway(vpc)
self._verify_resource_is_in_stack(vpc.internet_gateway,
stack,
unique=True)
self._verify_resource_is_in_stack(vpc.internet_gateway_attachment,
stack,
unique=True)
# Verify existing Internet Gateway is used
assert vpc.internet_gateway is igw
assert vpc.internet_gateway_attachment is attachment
def test_should_throw_error_when_called_a_second_time_with_wrong_stack(
self):
# Setup: Create stack with gateway
stack = Stack()
stack.Resources["MyVPC"] = vpc = VPC()
vpc.ensure_internet_gateway_exists(stack)
# Setup: Create second stack
unrelated_stack = Stack()
# Exercise & Verify
with pytest.raises(RuntimeError) as excinfo:
vpc.ensure_internet_gateway_exists(unrelated_stack)
assert "not in this stack" in str(excinfo.value)
def test_should_create_resources_in_stack(self):
# Setup
stack = Stack()
stack.Resources["MyVPC"] = vpc = VPC()
# Exercise
vpc.ensure_internet_gateway_exists(stack)
# Verify
self._verify_vpc_has_valid_internet_gateway(vpc)
self._verify_resource_is_in_stack(vpc.internet_gateway,
stack,
unique=True)
self._verify_resource_is_in_stack(vpc.internet_gateway_attachment,
stack,
unique=True)
def test_should_not_use_existing_non_igw_attached_to_vpc_in_stack(self):
# Setup
stack = Stack()
stack.Resources["MyVPC"] = vpc = VPC()
stack.Resources["MyGateway"] = vpn_gateway = VPNGateway(
Properties=dict(Type="ipsec.1"))
stack.Resources[
"MyGatewayAttachment"] = attachment = VPCGatewayAttachment(
Properties=dict(VpcId=Ref(vpc), VpnGatewayId=Ref(vpn_gateway)))
# Exercise
vpc.ensure_internet_gateway_exists(stack)
# Verify
self._verify_vpc_has_valid_internet_gateway(vpc)
self._verify_resource_is_in_stack(vpc.internet_gateway,
stack,
unique=True)
self._verify_resource_is_in_stack(vpc.internet_gateway_attachment,
stack)
# Verify existing Internet Gateway is not used
assert attachment is not vpc.internet_gateway_attachment
self._verify_resource_is_in_stack(attachment, stack)