Importer: Add resource_types flag (#779)

* Support interactive correctly

* Add --resources flag to tfimport

* Switch to specific resource types

* Remove leftover from branch

* Fix custom type repr

cmd/tfimport/main.go

@@ -16,10 +16,11 @@
 // Requires Terraform to be installed and for authentication to be configured for each provider in the Terraform configs provider blocks.
 //
 // Usage:
-// $ go run . [--input_dir=/path/to/config]
+// $ go run . [--input_dir=/path/to/config] [--resource_types 'google_storage_bucket.bucket' --resources 'google_resource_manager_lien.lien']
 package main
 
 import (
+	"encoding/json"
 	"flag"
 	"fmt"
 	"log"
@@ -29,6 +30,23 @@ import (
 	"github.com/GoogleCloudPlatform/healthcare-data-protection-suite/internal/tfimport"
 )
 
+// From https://stackoverflow.com/a/28323276
+type mapFlag map[string]bool
+
+func (i *mapFlag) String() string {
+	if b, err := json.Marshal(*i); err == nil {
+		return string(b)
+	}
+	return ""
+}
+
+func (i *mapFlag) Set(value string) error {
+	(*i)[value] = true
+	return nil
+}
+
+var resourcesFlag = make(mapFlag)
+
 var (
 	inputDir      = flag.String("input_dir", ".", "Path to the directory containing Terraform configs.")
 	terraformPath = flag.String("terraform_path", "terraform", "Name or path to the terraform binary to use.")
@@ -38,6 +56,8 @@ var (
 )
 
 func main() {
+	flag.Var(&resourcesFlag, "resource_types", "Specific resource types to import, specified as terraform resource names (e.g. 'google_storage_bucket', 'google_resource_manager_lien'). Leave empty to import all.")
+
 	if err := run(); err != nil {
 		log.Fatal(err)
 	}
@@ -66,10 +86,11 @@ func run() error {
 	}
 
 	args := &tfimport.RunArgs{
-		InputDir:      *inputDir,
-		TerraformPath: *terraformPath,
-		DryRun:        *dryRun,
-		Interactive:   *interactive,
+		InputDir:              *inputDir,
+		TerraformPath:         *terraformPath,
+		DryRun:                *dryRun,
+		Interactive:           *interactive,
+		SpecificResourceTypes: resourcesFlag,
 	}
 
 	if err := tfimport.Run(rn, importRn, args); err != nil {

internal/tfimport/tfimport.go

@@ -522,6 +522,10 @@ type RunArgs struct {
 	TerraformPath string
 	DryRun        bool
 	Interactive   bool
+
+	// This is a "set" of resource types to import.
+	// If not nil and not empty, will import only resources which match it.
+	SpecificResourceTypes map[string]bool
 }
 
 // Run executes the main tfimport logic.
@@ -614,6 +618,14 @@ func planAndImport(rn, importRn runner.Runner, runArgs *RunArgs) (retry bool, er
 
 		log.Printf("Found importable resource: %q\n", ir.Change.Address)
 
+		// Check against specific resources list, if present.
+		if len(runArgs.SpecificResourceTypes) > 0 {
+			if _, ok := runArgs.SpecificResourceTypes[ir.Change.Kind]; !ok {
+				log.Printf("Skipping %v, not in list of specific resource types to import", ir.Change.Address)
+				continue
+			}
+		}
+
 		// Attempt the import.
 		output, err := Import(importRn, ir, runArgs.InputDir, runArgs.TerraformPath, runArgs.Interactive)