feat: Link Gateway V2 APIs to Lambda Functions (#5626)

* feat: Link gateway v2 apis to lambda functions

* Fix typo

* Format files

samcli/hook_packages/terraform/hooks/prepare/exceptions.py

@@ -287,6 +287,18 @@ class GatewayV2RouteToGatewayV2ApiLocalVariablesLinkingLimitationException(Local
     """
 
 
+class OneGatewayV2ApiToLambdaFunctionLinkingLimitationException(OneResourceLinkingLimitationException):
+    """
+    Exception specific for Gateway V2 API linking to more than one Lambda Function
+    """
+
+
+class GatewayV2ApiToLambdaFunctionLocalVariablesLinkingLimitationException(LocalVariablesLinkingLimitationException):
+    """
+    Exception specific for Gateway V2 API linking to Lambda Function using locals.
+    """
+
+
 class OneGatewayV2StageToGatewayV2ApiLinkingLimitationException(OneResourceLinkingLimitationException):
     """
     Exception specific for Gateway V2 Stage linking to more than one Gateway V2 API

samcli/hook_packages/terraform/hooks/prepare/resource_linking.py

@@ -16,6 +16,7 @@
     GatewayResourceToApiGatewayIntegrationResponseLocalVariablesLinkingLimitationException,
     GatewayResourceToApiGatewayMethodLocalVariablesLinkingLimitationException,
     GatewayResourceToGatewayRestApiLocalVariablesLinkingLimitationException,
+    GatewayV2ApiToLambdaFunctionLocalVariablesLinkingLimitationException,
     GatewayV2IntegrationToGatewayV2ApiLocalVariablesLinkingLimitationException,
     GatewayV2IntegrationToLambdaFunctionLocalVariablesLinkingLimitationException,
     GatewayV2RouteToGatewayV2ApiLocalVariablesLinkingLimitationException,
@@ -31,6 +32,7 @@
     OneGatewayResourceToApiGatewayIntegrationResponseLinkingLimitationException,
     OneGatewayResourceToApiGatewayMethodLinkingLimitationException,
     OneGatewayResourceToRestApiLinkingLimitationException,
+    OneGatewayV2ApiToLambdaFunctionLinkingLimitationException,
     OneGatewayV2IntegrationToGatewayV2ApiLinkingLimitationException,
     OneGatewayV2IntegrationToLambdaFunctionLinkingLimitationException,
     OneGatewayV2RouteToGatewayV2ApiLinkingLimitationException,
@@ -2006,6 +2008,82 @@ def _link_gateway_v2_route_to_api(
     ResourceLinker(resource_linking_pair).link_resources()
 
 
+def _link_gateway_v2_api_to_function_callback(
+    gateway_v2_api_cfn_resource: Dict, referenced_function_resource_values: List[ReferenceType]
+) -> None:
+    """
+    Callback function that is used by the linking algorithm to update an Api Gateway V2 API CFN Resource with
+    a reference to the Lambda function resource through the AWS_PROXY integration.
+
+    Parameters
+    ----------
+    gateway_v2_api_cfn_resource: Dict
+        API Gateway V2 API CFN resource
+    referenced_function_resource_values: List[ReferenceType]
+        List of referenced Gateway Resources either as the logical id of Lambda function resource
+        defined in the customer project, or ARN values for actual Lambda function resource defined
+        in customer's account. This list should always contain one element only.
+    """
+    if len(referenced_function_resource_values) > 1:
+        raise InvalidResourceLinkingException("Could not link a V2 API to more than one Lambda Function resources")
+
+    if not referenced_function_resource_values:
+        LOG.info("Unable to find any references to Lambda functions, skip linking Lambda function to Gateway V2 API")
+        return
+
+    logical_id = referenced_function_resource_values[0]
+    gateway_v2_api_cfn_resource["Properties"]["Target"] = (
+        {"Fn::Sub": INVOKE_ARN_FORMAT.format(function_logical_id=logical_id.value)}
+        if isinstance(logical_id, LogicalIdReference)
+        else logical_id.value
+    )
+
+
+def _link_gateway_v2_api_to_function(
+    gateway_api_config_resources: Dict[str, TFResource],
+    gateway_api_config_address_cfn_resources_map: Dict[str, List],
+    lambda_function_resources: Dict[str, Dict],
+) -> None:
+    """
+    Iterate through all the resources and link the corresponding
+    Gateway V2 API resources to each Lambda Function
+
+    Parameters
+    ----------
+    gateway_api_config_resources: Dict[str, TFResource]
+        Dictionary of configuration Gateway APIs
+    gateway_api_config_address_cfn_resources_map: Dict[str, List]
+        Dictionary containing resolved configuration addresses matched up to the cfn Gateway API
+    lambda_function_resources: Dict[str, Dict]
+        Dictionary of all Terraform Lambda Function resources (not configuration resources).
+        The dictionary's key is the calculated logical id for each resource.
+    """
+
+    # Only link APIs to resources if they are "Quick Create" APIs
+    quick_create_api_config_resources = {
+        config_address: tf_resource
+        for config_address, tf_resource in gateway_api_config_resources.items()
+        if "target" in tf_resource.attributes
+    }
+
+    exceptions = ResourcePairExceptions(
+        multiple_resource_linking_exception=OneGatewayV2ApiToLambdaFunctionLinkingLimitationException,
+        local_variable_linking_exception=GatewayV2ApiToLambdaFunctionLocalVariablesLinkingLimitationException,
+    )
+    resource_linking_pair = ResourceLinkingPair(
+        source_resource_cfn_resource=gateway_api_config_address_cfn_resources_map,
+        source_resource_tf_config=quick_create_api_config_resources,
+        destination_resource_tf=lambda_function_resources,
+        tf_destination_attribute_name="invoke_arn",
+        terraform_link_field_name="target",
+        cfn_link_field_name="Target",
+        terraform_resource_type_prefix=LAMBDA_FUNCTION_RESOURCE_ADDRESS_PREFIX,
+        cfn_resource_update_call_back_function=_link_gateway_v2_api_to_function_callback,
+        linking_exceptions=exceptions,
+    )
+    ResourceLinker(resource_linking_pair).link_resources()
+
+
 def _link_gateway_v2_stage_to_api(
     gateway_stage_config_resources: Dict[str, TFResource],
     gateway_stage_config_address_cfn_resources_map: Dict[str, List],

samcli/hook_packages/terraform/hooks/prepare/resources/resource_links.py

@@ -28,6 +28,7 @@
     _link_gateway_methods_to_gateway_rest_apis,
     _link_gateway_resources_to_gateway_rest_apis,
     _link_gateway_stage_to_rest_api,
+    _link_gateway_v2_api_to_function,
     _link_gateway_v2_integration_to_api,
     _link_gateway_v2_integration_to_lambda_function,
     _link_gateway_v2_route_to_api,
@@ -119,6 +120,11 @@
         dest=TF_AWS_API_GATEWAY_V2_API,
         linking_func=_link_gateway_v2_route_to_api,
     ),
+    LinkingPairCaller(
+        source=TF_AWS_API_GATEWAY_V2_API,
+        dest=TF_AWS_LAMBDA_FUNCTION,
+        linking_func=_link_gateway_v2_api_to_function,
+    ),
     LinkingPairCaller(
         source=TF_AWS_API_GATEWAY_V2_STAGE,
         dest=TF_AWS_API_GATEWAY_V2_API,

tests/unit/hook_packages/terraform/hooks/prepare/test_resource_linking.py

@@ -45,6 +45,8 @@
     GatewayV2IntegrationToGatewayV2ApiLocalVariablesLinkingLimitationException,
     OneGatewayV2RouteToGatewayV2ApiLinkingLimitationException,
     GatewayV2RouteToGatewayV2ApiLocalVariablesLinkingLimitationException,
+    OneGatewayV2ApiToLambdaFunctionLinkingLimitationException,
+    GatewayV2ApiToLambdaFunctionLocalVariablesLinkingLimitationException,
     OneGatewayV2StageToGatewayV2ApiLinkingLimitationException,
     GatewayV2StageToGatewayV2ApiLocalVariablesLinkingLimitationException,
 )
@@ -101,6 +103,8 @@
     API_GATEWAY_V2_API_RESOURCE_ADDRESS_PREFIX,
     _link_gateway_v2_resource_to_api_callback,
     _link_gateway_v2_route_to_api,
+    _link_gateway_v2_api_to_function,
+    _link_gateway_v2_api_to_function_callback,
     _link_gateway_v2_stage_to_api,
 )
 from samcli.hook_packages.terraform.hooks.prepare.utilities import get_configuration_address
@@ -2141,6 +2145,10 @@ def test_link_gateway_integration_to_function_call_back(
                 _link_gateway_v2_resource_to_api_callback,
                 "Could not link multiple Gateway V2 Apis to one Gateway V2 resource",
             ),
+            (
+                _link_gateway_v2_api_to_function_callback,
+                "Could not link a V2 API to more than one Lambda Function resources",
+            ),
         ]
     )
     def test_linking_callbacks_raises_multiple_reference_exception(self, linking_call_back_method, expected_message):
@@ -2158,6 +2166,7 @@ def test_linking_callbacks_raises_multiple_reference_exception(self, linking_cal
             (_link_gateway_v2_route_to_integration_callback,),
             (_link_gateway_v2_integration_to_lambda_function_callback,),
             (_link_gateway_v2_resource_to_api_callback,),
+            (_link_gateway_v2_api_to_function_callback,),
         ]
     )
     def test_linking_callbacks_skips_empty_references(self, linking_call_back_method):
@@ -2727,3 +2736,72 @@ def test_link_gateway_v2_integration_to_api_callback(
         _link_gateway_v2_resource_to_api_callback(gateway_resource, logical_ids)
         input_gateway_v2_integration["Properties"]["ApiId"] = expected_api_reference
         self.assertEqual(gateway_resource, input_gateway_v2_integration)
+
+    @patch("samcli.hook_packages.terraform.hooks.prepare.resource_linking._link_gateway_v2_api_to_function_callback")
+    @patch("samcli.hook_packages.terraform.hooks.prepare.resource_linking.ResourceLinker")
+    @patch("samcli.hook_packages.terraform.hooks.prepare.resource_linking.ResourceLinkingPair")
+    @patch("samcli.hook_packages.terraform.hooks.prepare.resource_linking.ResourcePairExceptions")
+    def test_link_gateway_v2_api_to_lambda_function(
+        self,
+        mock_resource_linking_exceptions,
+        mock_resource_linking_pair,
+        mock_resource_linker,
+        mock_link_gateway_v2_api_to_function_callback,
+    ):
+        api_v2_cfn_resources = Mock()
+        quick_create_resource = TFResource("resource_address", "type", Mock(), {"target": ConstantValue("val")})
+        combined_resources = {
+            "ResourceA": quick_create_resource,
+            "ResourceB": TFResource("resource_address", "type", Mock(), {"name": ConstantValue("MyAPI")}),
+        }
+        expected_quick_create_resource = {"ResourceA": quick_create_resource}
+        lambda_function_tf_resources = Mock()
+
+        _link_gateway_v2_api_to_function(combined_resources, api_v2_cfn_resources, lambda_function_tf_resources)
+
+        mock_resource_linking_exceptions.assert_called_once_with(
+            multiple_resource_linking_exception=OneGatewayV2ApiToLambdaFunctionLinkingLimitationException,
+            local_variable_linking_exception=GatewayV2ApiToLambdaFunctionLocalVariablesLinkingLimitationException,
+        )
+
+        mock_resource_linking_pair.assert_called_once_with(
+            source_resource_cfn_resource=api_v2_cfn_resources,
+            source_resource_tf_config=expected_quick_create_resource,
+            destination_resource_tf=lambda_function_tf_resources,
+            tf_destination_attribute_name="invoke_arn",
+            terraform_link_field_name="target",
+            cfn_link_field_name="Target",
+            terraform_resource_type_prefix=LAMBDA_FUNCTION_RESOURCE_ADDRESS_PREFIX,
+            cfn_resource_update_call_back_function=mock_link_gateway_v2_api_to_function_callback,
+            linking_exceptions=mock_resource_linking_exceptions(),
+        )
+
+        mock_resource_linker.assert_called_once_with(mock_resource_linking_pair())
+
+    @parameterized.expand(
+        [
+            (
+                {
+                    "Type": "AWS::ApiGatewayV2::Api",
+                    "Properties": {"Target": "functionA.invoke_arn"},
+                },
+                [LogicalIdReference("FunctionA")],
+                {
+                    "Fn::Sub": "arn:${AWS::Partition}:apigateway:${AWS::Region}:lambda:path/2015-03-31/functions/${FunctionA.Arn}/invocations"
+                },
+            ),
+            (
+                {
+                    "Type": "AWS::ApiGatewayV2::Api",
+                    "Properties": {"Target": "functionA.invoke_arn"},
+                },
+                [ExistingResourceReference("myapi_arn")],
+                "myapi_arn",
+            ),
+        ]
+    )
+    def test_link_gateway_v2_api_to_function_callback(self, input_gateway_v2_api, logical_ids, expected_api_reference):
+        gateway_resource = deepcopy(input_gateway_v2_api)
+        _link_gateway_v2_api_to_function_callback(gateway_resource, logical_ids)
+        input_gateway_v2_api["Properties"]["Target"] = expected_api_reference
+        self.assertEqual(gateway_resource, input_gateway_v2_api)