Add GetModulePath method (#171)

Author: wata727

helper/runner.go

@@ -6,6 +6,7 @@ import (
 
 	"github.com/hashicorp/hcl/v2"
 	"github.com/terraform-linters/tflint-plugin-sdk/hclext"
+	"github.com/terraform-linters/tflint-plugin-sdk/terraform/addrs"
 	"github.com/terraform-linters/tflint-plugin-sdk/tflint"
 	"github.com/zclconf/go-cty/cty"
 	"github.com/zclconf/go-cty/cty/convert"
@@ -42,6 +43,11 @@ type RuleConfig struct {
 
 var _ tflint.Runner = &Runner{}
 
+// GetModulePath always returns the root module path address
+func (r *Runner) GetModulePath() (addrs.Module, error) {
+	return []string{}, nil
+}
+
 // GetModuleContent gets a content of the current module
 func (r *Runner) GetModuleContent(schema *hclext.BodySchema, opts *tflint.GetModuleContentOption) (*hclext.BodyContent, error) {
 	content := &hclext.BodyContent{}

plugin/host2plugin/host2plugin_test.go

@@ -463,6 +463,10 @@ type mockServerImpl struct {
 	getFile func(string) (*hcl.File, error)
 }
 
+func (s *mockServer) GetModulePath() []string {
+	return []string{}
+}
+
 func (s *mockServer) GetModuleContent(schema *hclext.BodySchema, opts tflint.GetModuleContentOption) (*hclext.BodyContent, hcl.Diagnostics) {
 	return &hclext.BodyContent{}, hcl.Diagnostics{}
 }

plugin/plugin2host/client.go

@@ -13,6 +13,7 @@ import (
 	"github.com/terraform-linters/tflint-plugin-sdk/plugin/fromproto"
 	"github.com/terraform-linters/tflint-plugin-sdk/plugin/proto"
 	"github.com/terraform-linters/tflint-plugin-sdk/plugin/toproto"
+	"github.com/terraform-linters/tflint-plugin-sdk/terraform/addrs"
 	"github.com/terraform-linters/tflint-plugin-sdk/tflint"
 	"github.com/zclconf/go-cty/cty"
 	"github.com/zclconf/go-cty/cty/gocty"
@@ -27,6 +28,15 @@ type GRPCClient struct {
 
 var _ tflint.Runner = &GRPCClient{}
 
+// GetModulePath gets the current module path address.
+func (c *GRPCClient) GetModulePath() (addrs.Module, error) {
+	resp, err := c.Client.GetModulePath(context.Background(), &proto.GetModulePath_Request{})
+	if err != nil {
+		return nil, fromproto.Error(err)
+	}
+	return resp.Path, err
+}
+
 // GetResourceContent gets the contents of resources based on the schema.
 // This is shorthand of GetModuleContent for resources
 func (c *GRPCClient) GetResourceContent(name string, inner *hclext.BodySchema, opts *tflint.GetModuleContentOption) (*hclext.BodyContent, error) {

plugin/plugin2host/plugin2host_test.go

@@ -14,6 +14,7 @@ import (
 	"github.com/hashicorp/hcl/v2/json"
 	"github.com/terraform-linters/tflint-plugin-sdk/hclext"
 	"github.com/terraform-linters/tflint-plugin-sdk/plugin/proto"
+	"github.com/terraform-linters/tflint-plugin-sdk/terraform/addrs"
 	"github.com/terraform-linters/tflint-plugin-sdk/tflint"
 	"github.com/zclconf/go-cty/cty"
 	"google.golang.org/grpc"
@@ -34,6 +35,7 @@ type mockServer struct {
 }
 
 type mockServerImpl struct {
+	getModulePath        func() []string
 	getModuleContent     func(*hclext.BodySchema, tflint.GetModuleContentOption) (*hclext.BodyContent, hcl.Diagnostics)
 	getFile              func(string) (*hcl.File, error)
 	getFiles             func() map[string][]byte
@@ -46,6 +48,13 @@ func newMockServer(impl mockServerImpl) *mockServer {
 	return &mockServer{impl: impl}
 }
 
+func (s *mockServer) GetModulePath() []string {
+	if s.impl.getModulePath != nil {
+		return s.impl.getModulePath()
+	}
+	return []string{}
+}
+
 func (s *mockServer) GetModuleContent(schema *hclext.BodySchema, opts tflint.GetModuleContentOption) (*hclext.BodyContent, hcl.Diagnostics) {
 	if s.impl.getModuleContent != nil {
 		return s.impl.getModuleContent(schema, opts)
@@ -91,6 +100,43 @@ func (s *mockServer) EmitIssue(rule tflint.Rule, message string, location hcl.Ra
 // @see https://github.com/google/go-cmp/issues/40
 var allowAllUnexported = cmp.Exporter(func(reflect.Type) bool { return true })
 
+func TestGetModulePath(t *testing.T) {
+	tests := []struct {
+		Name       string
+		ServerImpl func() []string
+		Want       addrs.Module
+	}{
+		{
+			Name: "get root module path",
+			ServerImpl: func() []string {
+				return []string{}
+			},
+			Want: nil,
+		},
+		{
+			Name: "get child module path",
+			ServerImpl: func() []string {
+				return []string{"child1", "child2"}
+			},
+			Want: []string{"child1", "child2"},
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.Name, func(t *testing.T) {
+			client := startTestGRPCServer(t, newMockServer(mockServerImpl{getModulePath: test.ServerImpl}))
+
+			got, err := client.GetModulePath()
+			if err != nil {
+				t.Fatalf("failed to call GetModulePath: %s", err)
+			}
+			if diff := cmp.Diff(got, test.Want); diff != "" {
+				t.Errorf("diff: %s", diff)
+			}
+		})
+	}
+}
+
 func TestGetResourceContent(t *testing.T) {
 	// default error check helper
 	neverHappend := func(err error) bool { return err != nil }

plugin/plugin2host/server.go

@@ -28,6 +28,7 @@ var _ proto.RunnerServer = &GRPCServer{}
 
 // Server is the interface that the host should implement when a plugin communicates with the host.
 type Server interface {
+	GetModulePath() []string
 	GetModuleContent(*hclext.BodySchema, tflint.GetModuleContentOption) (*hclext.BodyContent, hcl.Diagnostics)
 	GetFile(string) (*hcl.File, error)
 	// For performance, GetFiles returns map[string][]bytes instead of map[string]*hcl.File.
@@ -37,6 +38,11 @@ type Server interface {
 	EmitIssue(rule tflint.Rule, message string, location hcl.Range) error
 }
 
+// GetModulePath gets the current module path address.
+func (s *GRPCServer) GetModulePath(ctx context.Context, req *proto.GetModulePath_Request) (*proto.GetModulePath_Response, error) {
+	return &proto.GetModulePath_Response{Path: s.Impl.GetModulePath()}, nil
+}
+
 // GetModuleContent gets the contents of the module based on the schema.
 func (s *GRPCServer) GetModuleContent(ctx context.Context, req *proto.GetModuleContent_Request) (*proto.GetModuleContent_Response, error) {
 	if req.Schema == nil {