Add aws_internet_gateway resource

doc/cmd/scan/supported_resources/aws.md

@@ -46,6 +46,7 @@ As AWS documentation recommends, the below policy is granting only the permissio
                 "ec2:DescribeInstanceAttribute",
                 "ec2:DescribeInstances",
                 "ec2:DescribeInstanceCreditSpecifications",
+                "ec2:DescribeInternetGateways",
                 "ec2:DescribeKeyPairs",
                 "ec2:DescribeNetworkAcls",
                 "ec2:DescribeRouteTables",
@@ -123,7 +124,6 @@ As AWS documentation recommends, the below policy is granting only the permissio
 - [ ] aws_s3_bucket_object
 - [ ] aws_s3_bucket_public_access_block
 
-
 ## EC2
 
 - [x] aws_instance
@@ -214,3 +214,4 @@ As AWS documentation recommends, the below policy is granting only the permissio
 - [x] aws_route
 - [x] aws_route_table_association
 - [x] aws_nat_gateway
+- [x] aws_internet_gateway

pkg/driftctl.go

@@ -38,6 +38,7 @@ func (d DriftCTL) Run() *analyser.Analysis {
 		middlewares.NewVPCSecurityGroupRuleSanitizer(),
 		middlewares.NewIamPolicyAttachmentSanitizer(),
 		middlewares.AwsInstanceEIP{},
+		middlewares.NewAwsDefaultInternetGateway(),
 		middlewares.NewAwsDefaultVPC(),
 		middlewares.NewAwsDefaultSubnet(),
 		middlewares.NewAwsRouteTableExpander(),

pkg/iac/deserializers.go

@@ -46,5 +46,6 @@ func Deserializers() []deserializer.CTYDeserializer {
 		awsdeserializer.NewRouteDeserializer(),
 		awsdeserializer.NewRouteTableAssociationDeserializer(),
 		awsdeserializer.NewNatGatewayDeserializer(),
+		awsdeserializer.NewInternetGatewayDeserializer(),
 	}
 }

pkg/iac/terraform/state/terraform_state_reader_test.go

@@ -72,6 +72,7 @@ func TestTerraformStateReader_Resources(t *testing.T) {
 		{name: "route", dirName: "route", wantErr: false},
 		{name: "route table associations", dirName: "route_assoc", wantErr: false},
 		{name: "NAT gateway", dirName: "aws_nat_gateway", wantErr: false},
+		{name: "Internet Gateway", dirName: "internet_gateway", wantErr: false},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {

pkg/iac/terraform/state/test/internet_gateway/result.golden.json

@@ -0,0 +1,11 @@
+[
+ {
+  "Arn": "arn:aws:ec2:eu-west-3:047081014315:internet-gateway/igw-0184eb41aadc62d1c",
+  "Id": "igw-0184eb41aadc62d1c",
+  "OwnerId": "047081014315",
+  "Tags": {
+   "Name": "main"
+  },
+  "VpcId": "vpc-0f3ac2b7909b6bedd"
+ }
+]

pkg/iac/terraform/state/test/internet_gateway/terraform.tfstate

@@ -0,0 +1,34 @@
+{
+  "version": 4,
+  "terraform_version": "0.14.4",
+  "serial": 559,
+  "lineage": "cc4be827-a907-1623-961b-0fc1ce33973e",
+  "outputs": {},
+  "resources": [
+    {
+      "mode": "managed",
+      "type": "aws_internet_gateway",
+      "name": "main",
+      "provider": "provider[\"registry.terraform.io/hashicorp/aws\"]",
+      "instances": [
+        {
+          "schema_version": 0,
+          "attributes": {
+            "arn": "arn:aws:ec2:eu-west-3:047081014315:internet-gateway/igw-0184eb41aadc62d1c",
+            "id": "igw-0184eb41aadc62d1c",
+            "owner_id": "047081014315",
+            "tags": {
+              "Name": "main"
+            },
+            "vpc_id": "vpc-0f3ac2b7909b6bedd"
+          },
+          "sensitive_attributes": [],
+          "private": "bnVsbA==",
+          "dependencies": [
+            "aws_vpc.vpc"
+          ]
+        }
+      ]
+    }
+  ]
+}

pkg/middlewares/aws_default_internet_gateway.go

@@ -0,0 +1,69 @@
+package middlewares
+
+import (
+	"github.com/cloudskiff/driftctl/pkg/resource"
+	"github.com/cloudskiff/driftctl/pkg/resource/aws"
+	"github.com/sirupsen/logrus"
+)
+
+// Each default vpc has an internet gateway attached that should not be seen as unmanaged if not managed by IaC
+// This middleware ignores default internet gateway from unmanaged resources if not managed by IaC
+type AwsDefaultInternetGateway struct{}
+
+func NewAwsDefaultInternetGateway() AwsDefaultInternetGateway {
+	return AwsDefaultInternetGateway{}
+}
+
+func (m AwsDefaultInternetGateway) Execute(remoteResources, resourcesFromState *[]resource.Resource) error {
+	newRemoteResources := make([]resource.Resource, 0)
+
+	for _, remoteResource := range *remoteResources {
+		// Ignore all resources other than internet gateways
+		if remoteResource.TerraformType() != aws.AwsInternetGatewayResourceType {
+			newRemoteResources = append(newRemoteResources, remoteResource)
+			continue
+		}
+
+		internetGateway, _ := remoteResource.(*aws.AwsInternetGateway)
+		// Ignore all non-default internet gateways
+		if !isDefaultInternetGateway(internetGateway, remoteResources) {
+			newRemoteResources = append(newRemoteResources, remoteResource)
+			continue
+		}
+
+		// Check if internet gateway is managed by IaC
+		existInState := false
+		for _, stateResource := range *resourcesFromState {
+			if resource.IsSameResource(remoteResource, stateResource) {
+				existInState = true
+				break
+			}
+		}
+
+		// Include resource if it's managed in IaC
+		if existInState {
+			newRemoteResources = append(newRemoteResources, remoteResource)
+			continue
+		}
+
+		// Else, resource is not added to newRemoteResources slice so it will be ignored
+		logrus.WithFields(logrus.Fields{
+			"id":   internetGateway.TerraformId(),
+			"type": internetGateway.TerraformType(),
+		}).Debug("Ignoring default internet gateway as it is not managed by IaC")
+	}
+
+	*remoteResources = newRemoteResources
+
+	return nil
+}
+
+// Return true if the internet gateway is the default one (e.g. attached to the default vpc)
+func isDefaultInternetGateway(internetGateway *aws.AwsInternetGateway, remoteResources *[]resource.Resource) bool {
+	for _, remoteResource := range *remoteResources {
+		if remoteResource.TerraformType() == aws.AwsDefaultVpcResourceType {
+			return *internetGateway.VpcId == remoteResource.TerraformId()
+		}
+	}
+	return false
+}

pkg/middlewares/aws_default_internet_gateway_test.go

@@ -0,0 +1,126 @@
+package middlewares
+
+import (
+	"strings"
+	"testing"
+
+	awssdk "github.com/aws/aws-sdk-go/aws"
+	"github.com/aws/aws-sdk-go/aws/awsutil"
+	"github.com/cloudskiff/driftctl/pkg/resource"
+	"github.com/cloudskiff/driftctl/pkg/resource/aws"
+	resource2 "github.com/cloudskiff/driftctl/test/resource"
+	"github.com/r3labs/diff/v2"
+)
+
+func TestAwsDefaultInternetGateway_Execute(t *testing.T) {
+	tests := []struct {
+		name               string
+		remoteResources    []resource.Resource
+		resourcesFromState []resource.Resource
+		expected           []resource.Resource
+	}{
+		{
+			"default internet gateway is not ignored when managed by IaC",
+			[]resource.Resource{
+				&resource2.FakeResource{
+					Id: "fake",
+				},
+				&aws.AwsDefaultVpc{
+					Id: "default-vpc",
+				},
+				&aws.AwsVpc{
+					Id: "dummy-vpc",
+				},
+				&aws.AwsInternetGateway{
+					Id:    "default-igw",
+					VpcId: awssdk.String("default-vpc"),
+				},
+				&aws.AwsInternetGateway{
+					Id:    "dummy-igw",
+					VpcId: awssdk.String("dummy-vpc"),
+				},
+			},
+			[]resource.Resource{
+				&aws.AwsInternetGateway{
+					Id:    "default-igw",
+					VpcId: awssdk.String("default-vpc"),
+				},
+			},
+			[]resource.Resource{
+				&resource2.FakeResource{
+					Id: "fake",
+				},
+				&aws.AwsDefaultVpc{
+					Id: "default-vpc",
+				},
+				&aws.AwsVpc{
+					Id: "dummy-vpc",
+				},
+				&aws.AwsInternetGateway{
+					Id:    "default-igw",
+					VpcId: awssdk.String("default-vpc"),
+				},
+				&aws.AwsInternetGateway{
+					Id:    "dummy-igw",
+					VpcId: awssdk.String("dummy-vpc"),
+				},
+			},
+		},
+		{
+			"default internet gateway is ignored when not managed by IaC",
+			[]resource.Resource{
+				&resource2.FakeResource{
+					Id: "fake",
+				},
+				&aws.AwsDefaultVpc{
+					Id: "default-vpc",
+				},
+				&aws.AwsVpc{
+					Id: "dummy-vpc",
+				},
+				&aws.AwsInternetGateway{
+					Id:    "default-igw",
+					VpcId: awssdk.String("default-vpc"),
+				},
+				&aws.AwsInternetGateway{
+					Id:    "dummy-igw",
+					VpcId: awssdk.String("dummy-vpc"),
+				},
+			},
+			[]resource.Resource{},
+			[]resource.Resource{
+				&resource2.FakeResource{
+					Id: "fake",
+				},
+				&aws.AwsDefaultVpc{
+					Id: "default-vpc",
+				},
+				&aws.AwsVpc{
+					Id: "dummy-vpc",
+				},
+				&aws.AwsInternetGateway{
+					Id:    "dummy-igw",
+					VpcId: awssdk.String("dummy-vpc"),
+				},
+			},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			m := NewAwsDefaultInternetGateway()
+			err := m.Execute(&tt.remoteResources, &tt.resourcesFromState)
+			if err != nil {
+				t.Fatal(err)
+			}
+			changelog, err := diff.Diff(tt.expected, tt.remoteResources)
+			if err != nil {
+				t.Fatal(err)
+			}
+			if len(changelog) > 0 {
+				for _, change := range changelog {
+					t.Errorf("%s got = %v, want %v", strings.Join(change.Path, "."), awsutil.Prettify(change.From), awsutil.Prettify(change.To))
+				}
+			}
+		})
+	}
+}

pkg/remote/aws/init.go

@@ -62,6 +62,7 @@ func Init(alerter *alerter.Alerter) error {
 	resource.AddSupplier(NewRouteSupplier(provider.Runner(), ec2.New(provider.session)))
 	resource.AddSupplier(NewRouteTableAssociationSupplier(provider.Runner(), ec2.New(provider.session)))
 	resource.AddSupplier(NewNatGatewaySupplier(provider.Runner(), ec2.New(provider.session)))
+	resource.AddSupplier(NewInternetGatewaySupplier(provider.Runner().SubRunner(), ec2.New(provider.session)))
 
 	return nil
 }

pkg/remote/aws/internet_gateway_supplier.go

@@ -0,0 +1,81 @@
+package aws
+
+import (
+	"github.com/aws/aws-sdk-go/service/ec2"
+	"github.com/aws/aws-sdk-go/service/ec2/ec2iface"
+	"github.com/cloudskiff/driftctl/pkg/parallel"
+	"github.com/cloudskiff/driftctl/pkg/remote/deserializer"
+	"github.com/cloudskiff/driftctl/pkg/resource"
+	"github.com/cloudskiff/driftctl/pkg/resource/aws"
+	awsdeserializer "github.com/cloudskiff/driftctl/pkg/resource/aws/deserializer"
+	"github.com/cloudskiff/driftctl/pkg/terraform"
+	"github.com/sirupsen/logrus"
+	"github.com/zclconf/go-cty/cty"
+)
+
+type InternetGatewaySupplier struct {
+	reader       terraform.ResourceReader
+	deserializer deserializer.CTYDeserializer
+	client       ec2iface.EC2API
+	runner       *terraform.ParallelResourceReader
+}
+
+func NewInternetGatewaySupplier(runner *parallel.ParallelRunner, client ec2iface.EC2API) *InternetGatewaySupplier {
+	return &InternetGatewaySupplier{
+		terraform.Provider(terraform.AWS),
+		awsdeserializer.NewInternetGatewayDeserializer(),
+		client,
+		terraform.NewParallelResourceReader(runner),
+	}
+}
+
+func (s InternetGatewaySupplier) Resources() ([]resource.Resource, error) {
+	internetGateways, err := listInternetGateways(s.client)
+	if err != nil {
+		return nil, err
+	}
+
+	for _, internetGateway := range internetGateways {
+		gtw := *internetGateway
+		s.runner.Run(func() (cty.Value, error) {
+			return s.readInternetGateway(gtw)
+		})
+	}
+
+	resources, err := s.runner.Wait()
+	if err != nil {
+		return nil, err
+	}
+
+	return s.deserializer.Deserialize(resources)
+}
+
+func (s InternetGatewaySupplier) readInternetGateway(internetGateway ec2.InternetGateway) (cty.Value, error) {
+	var Ty resource.ResourceType = aws.AwsInternetGatewayResourceType
+	val, err := s.reader.ReadResource(terraform.ReadResourceArgs{
+		Ty: Ty,
+		ID: *internetGateway.InternetGatewayId,
+	})
+	if err != nil {
+		logrus.WithFields(logrus.Fields{
+			"type": Ty,
+		}).Error(err)
+		return cty.NilVal, err
+	}
+	return *val, nil
+}
+
+func listInternetGateways(client ec2iface.EC2API) ([]*ec2.InternetGateway, error) {
+	var internetGateways []*ec2.InternetGateway
+	input := ec2.DescribeInternetGatewaysInput{}
+	err := client.DescribeInternetGatewaysPages(&input,
+		func(resp *ec2.DescribeInternetGatewaysOutput, lastPage bool) bool {
+			internetGateways = append(internetGateways, resp.InternetGateways...)
+			return !lastPage
+		},
+	)
+	if err != nil {
+		return nil, err
+	}
+	return internetGateways, nil
+}

pkg/remote/aws/internet_gateway_supplier_test.go

@@ -0,0 +1,98 @@
+package aws
+
+import (
+	"context"
+	"testing"
+
+	awssdk "github.com/aws/aws-sdk-go/aws"
+
+	"github.com/aws/aws-sdk-go/service/ec2"
+	"github.com/cloudskiff/driftctl/mocks"
+	"github.com/cloudskiff/driftctl/pkg/parallel"
+	"github.com/cloudskiff/driftctl/pkg/remote/deserializer"
+	"github.com/cloudskiff/driftctl/pkg/resource"
+	awsdeserializer "github.com/cloudskiff/driftctl/pkg/resource/aws/deserializer"
+	"github.com/cloudskiff/driftctl/pkg/terraform"
+	"github.com/cloudskiff/driftctl/test"
+	"github.com/cloudskiff/driftctl/test/goldenfile"
+	mocks2 "github.com/cloudskiff/driftctl/test/mocks"
+	"github.com/stretchr/testify/mock"
+)
+
+func TestInternetGatewaySupplier_Resources(t *testing.T) {
+	cases := []struct {
+		test    string
+		dirName string
+		mocks   func(client *mocks.FakeEC2)
+		err     error
+	}{
+		{
+			test:    "no internet gateways",
+			dirName: "internet_gateway_empty",
+			mocks: func(client *mocks.FakeEC2) {
+				client.On("DescribeInternetGatewaysPages",
+					&ec2.DescribeInternetGatewaysInput{},
+					mock.MatchedBy(func(callback func(res *ec2.DescribeInternetGatewaysOutput, lastPage bool) bool) bool {
+						callback(&ec2.DescribeInternetGatewaysOutput{}, true)
+						return true
+					})).Return(nil)
+			},
+			err: nil,
+		},
+		{
+			test:    "multiple internet gateways",
+			dirName: "internet_gateway_multiple",
+			mocks: func(client *mocks.FakeEC2) {
+				client.On("DescribeInternetGatewaysPages",
+					&ec2.DescribeInternetGatewaysInput{},
+					mock.MatchedBy(func(callback func(res *ec2.DescribeInternetGatewaysOutput, lastPage bool) bool) bool {
+						callback(&ec2.DescribeInternetGatewaysOutput{
+							InternetGateways: []*ec2.InternetGateway{
+								{
+									InternetGatewayId: awssdk.String("igw-0184eb41aadc62d1c"),
+								},
+								{
+									InternetGatewayId: awssdk.String("igw-047b487f5c60fca99"),
+								},
+							},
+						}, true)
+						return true
+					})).Return(nil)
+			},
+			err: nil,
+		},
+	}
+	for _, c := range cases {
+		shouldUpdate := c.dirName == *goldenfile.Update
+		if shouldUpdate {
+			provider, err := NewTerraFormProvider()
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			terraform.AddProvider(terraform.AWS, provider)
+			resource.AddSupplier(NewInternetGatewaySupplier(provider.Runner(), ec2.New(provider.session)))
+		}
+
+		t.Run(c.test, func(tt *testing.T) {
+			fakeEC2 := mocks.FakeEC2{}
+			c.mocks(&fakeEC2)
+			provider := mocks2.NewMockedGoldenTFProvider(c.dirName, terraform.Provider(terraform.AWS), shouldUpdate)
+			internetGatewayDeserializer := awsdeserializer.NewInternetGatewayDeserializer()
+			s := &InternetGatewaySupplier{
+				provider,
+				internetGatewayDeserializer,
+				&fakeEC2,
+				terraform.NewParallelResourceReader(parallel.NewParallelRunner(context.TODO(), 10)),
+			}
+			got, err := s.Resources()
+			if c.err != err {
+				tt.Errorf("Expected error %+v got %+v", c.err, err)
+			}
+
+			mock.AssertExpectationsForObjects(tt)
+			deserializers := []deserializer.CTYDeserializer{internetGatewayDeserializer}
+			test.CtyTestDiffMixed(got, c.dirName, provider, deserializers, shouldUpdate, tt)
+		})
+	}
+}

pkg/remote/aws/test/internet_gateway_empty/results.golden.json

@@ -0,0 +1 @@
+[]

pkg/remote/aws/test/internet_gateway_multiple/aws_internet_gateway-igw-0184eb41aadc62d1c.res.golden.json

@@ -0,0 +1,5 @@
+{
+ "Typ": "WyJvYmplY3QiLHsiYXJuIjoic3RyaW5nIiwiaWQiOiJzdHJpbmciLCJvd25lcl9pZCI6InN0cmluZyIsInRhZ3MiOlsibWFwIiwic3RyaW5nIl0sInZwY19pZCI6InN0cmluZyJ9XQ==",
+ "Val": "eyJhcm4iOiJhcm46YXdzOmVjMjpldS13ZXN0LTM6MDQ3MDgxMDE0MzE1OmludGVybmV0LWdhdGV3YXkvaWd3LTAxODRlYjQxYWFkYzYyZDFjIiwiaWQiOiJpZ3ctMDE4NGViNDFhYWRjNjJkMWMiLCJvd25lcl9pZCI6IjA0NzA4MTAxNDMxNSIsInRhZ3MiOnsiTmFtZSI6Im1haW4ifSwidnBjX2lkIjoidnBjLTBmM2FjMmI3OTA5YjZiZWRkIn0=",
+ "Err": null
+}

pkg/remote/aws/test/internet_gateway_multiple/aws_internet_gateway-igw-047b487f5c60fca99.res.golden.json

@@ -0,0 +1,5 @@
+{
+ "Typ": "WyJvYmplY3QiLHsiYXJuIjoic3RyaW5nIiwiaWQiOiJzdHJpbmciLCJvd25lcl9pZCI6InN0cmluZyIsInRhZ3MiOlsibWFwIiwic3RyaW5nIl0sInZwY19pZCI6InN0cmluZyJ9XQ==",
+ "Val": "eyJhcm4iOiJhcm46YXdzOmVjMjpldS13ZXN0LTM6MDQ3MDgxMDE0MzE1OmludGVybmV0LWdhdGV3YXkvaWd3LTA0N2I0ODdmNWM2MGZjYTk5IiwiaWQiOiJpZ3ctMDQ3YjQ4N2Y1YzYwZmNhOTkiLCJvd25lcl9pZCI6IjA0NzA4MTAxNDMxNSIsInRhZ3MiOnsiTmFtZSI6ImZvbyJ9LCJ2cGNfaWQiOiJ2cGMtMGE0MTY2MGRjODZjOGRlNWUifQ==",
+ "Err": null
+}

pkg/remote/aws/test/internet_gateway_multiple/results.golden.json

@@ -0,0 +1,20 @@
+[
+ {
+  "arn": "arn:aws:ec2:eu-west-3:047081014315:internet-gateway/igw-047b487f5c60fca99",
+  "id": "igw-047b487f5c60fca99",
+  "owner_id": "047081014315",
+  "tags": {
+   "Name": "foo"
+  },
+  "vpc_id": "vpc-0a41660dc86c8de5e"
+ },
+ {
+  "arn": "arn:aws:ec2:eu-west-3:047081014315:internet-gateway/igw-0184eb41aadc62d1c",
+  "id": "igw-0184eb41aadc62d1c",
+  "owner_id": "047081014315",
+  "tags": {
+   "Name": "main"
+  },
+  "vpc_id": "vpc-0f3ac2b7909b6bedd"
+ }
+]

pkg/remote/aws/test/internet_gateway_multiple/terraform.tf

@@ -0,0 +1,31 @@
+provider "aws" {
+  region = "us-east-1"
+}
+
+terraform {
+  required_providers {
+    aws = "3.19.0"
+  }
+}
+
+resource "aws_vpc" "vpc" {
+  cidr_block = "10.0.0.0/16"
+}
+
+resource "aws_internet_gateway" "main" {
+  vpc_id = aws_vpc.vpc.id
+  tags = {
+    Name = "main"
+  }
+}
+
+resource "aws_vpc" "vpc_bis" {
+  cidr_block = "10.1.0.0/16"
+}
+
+resource "aws_internet_gateway" "foo" {
+  vpc_id = aws_vpc.vpc_bis.id
+  tags = {
+    Name = "foo"
+  }
+}

pkg/resource/aws/aws_internet_gateway.go

@@ -0,0 +1,20 @@
+// GENERATED, DO NOT EDIT THIS FILE
+package aws
+
+const AwsInternetGatewayResourceType = "aws_internet_gateway"
+
+type AwsInternetGateway struct {
+	Arn     *string           `cty:"arn" computed:"true"`
+	Id      string            `cty:"id" computed:"true"`
+	OwnerId *string           `cty:"owner_id" computed:"true"`
+	Tags    map[string]string `cty:"tags"`
+	VpcId   *string           `cty:"vpc_id"`
+}
+
+func (r *AwsInternetGateway) TerraformId() string {
+	return r.Id
+}
+
+func (r *AwsInternetGateway) TerraformType() string {
+	return AwsInternetGatewayResourceType
+}

pkg/resource/aws/aws_internet_gateway_test.go

@@ -0,0 +1,28 @@
+package aws_test
+
+import (
+	"testing"
+
+	"github.com/cloudskiff/driftctl/test/acceptance"
+)
+
+func TestAcc_AwsInternetGateway(t *testing.T) {
+	acceptance.Run(t, acceptance.AccTestCase{
+		Path: "./testdata/acc/aws_internet_gateway",
+		Args: []string{"scan", "--filter", "Type=='aws_internet_gateway'"},
+		Checks: []acceptance.AccCheck{
+			{
+				Env: map[string]string{
+					"AWS_REGION": "us-east-1",
+				},
+				Check: func(result *acceptance.ScanResult, stdout string, err error) {
+					if err != nil {
+						t.Fatal(err)
+					}
+					result.AssertInfrastructureIsInSync()
+					result.Equal(1, result.Summary().TotalManaged)
+				},
+			},
+		},
+	})
+}

pkg/resource/aws/deserializer/internet_gateway_deserializer.go

@@ -0,0 +1,43 @@
+package deserializer
+
+import (
+	"github.com/cloudskiff/driftctl/pkg/resource"
+	resourceaws "github.com/cloudskiff/driftctl/pkg/resource/aws"
+	"github.com/sirupsen/logrus"
+	"github.com/zclconf/go-cty/cty"
+	"github.com/zclconf/go-cty/cty/gocty"
+)
+
+type InternetGatewayDeserializer struct {
+}
+
+func NewInternetGatewayDeserializer() *InternetGatewayDeserializer {
+	return &InternetGatewayDeserializer{}
+}
+
+func (s *InternetGatewayDeserializer) HandledType() resource.ResourceType {
+	return resourceaws.AwsInternetGatewayResourceType
+}
+
+func (s InternetGatewayDeserializer) Deserialize(rawList []cty.Value) ([]resource.Resource, error) {
+	resources := make([]resource.Resource, 0)
+	for _, rawResource := range rawList {
+		resource, err := decodeInternetGateway(&rawResource)
+		if err != nil {
+			logrus.WithFields(logrus.Fields{
+				"type": s.HandledType(),
+			}).Warnf("Error when deserializing resource %+v : %+v", rawResource, err)
+			return nil, err
+		}
+		resources = append(resources, resource)
+	}
+	return resources, nil
+}
+
+func decodeInternetGateway(raw *cty.Value) (*resourceaws.AwsInternetGateway, error) {
+	var decoded resourceaws.AwsInternetGateway
+	if err := gocty.FromCtyValue(*raw, &decoded); err != nil {
+		return nil, err
+	}
+	return &decoded, nil
+}

pkg/resource/aws/testdata/acc/aws_internet_gateway/.terraform.lock.hcl

@@ -0,0 +1,20 @@
+# This file is maintained automatically by "terraform init".
+# Manual edits may be lost in future updates.
+
+provider "registry.terraform.io/hashicorp/aws" {
+  version     = "3.19.0"
+  constraints = "3.19.0"
+  hashes = [
+    "h1:xur9tF49NgsovNnmwmBR8RdpN8Fcg1TD4CKQPJD6n1A=",
+    "zh:185a5259153eb9ee4699d4be43b3d509386b473683392034319beee97d470c3b",
+    "zh:2d9a0a01f93e8d16539d835c02b8b6e1927b7685f4076e96cb07f7dd6944bc6c",
+    "zh:703f6da36b1b5f3497baa38fccaa7765fb8a2b6440344e4c97172516b49437dd",
+    "zh:770855565462abadbbddd98cb357d2f1a8f30f68a358cb37cbd5c072cb15b377",
+    "zh:8008db43149fe4345301f81e15e6d9ddb47aa5e7a31648f9b290af96ad86e92a",
+    "zh:8cdd27d375da6dcb7687f1fed126b7c04efce1671066802ee876dbbc9c66ec79",
+    "zh:be22ae185005690d1a017c1b909e0d80ab567e239b4f06ecacdba85080667c1c",
+    "zh:d2d02e72dbd80f607636cd6237a6c862897caabc635c7b50c0cb243d11246723",
+    "zh:d8f125b66a1eda2555c0f9bbdf12036a5f8d073499a22ca9e4812b68067fea31",
+    "zh:f5a98024c64d5d2973ff15b093725a074c0cb4afde07ef32c542e69f17ac90bc",
+  ]
+}

pkg/resource/aws/testdata/acc/aws_internet_gateway/terraform.tf

@@ -0,0 +1,21 @@
+provider "aws" {
+  region = "us-east-1"
+}
+
+terraform {
+  required_providers {
+    aws = "3.19.0"
+  }
+}
+
+resource "aws_vpc" "vpc" {
+  cidr_block = "10.0.0.0/16"
+}
+
+resource "aws_internet_gateway" "main" {
+  vpc_id = aws_vpc.vpc.id
+
+  tags = {
+    Name = "main"
+  }
+}