resource/gitlab_label: Support import

Refs: #36

Author: timofurrer

docs/resources/label.md

@@ -46,4 +46,11 @@ resource "gitlab_label" "devops_create" {
 - **description** (String) The description of the label.
 - **id** (String) The ID of this resource.
 
+## Import
 
+Import is supported using the following syntax:
+
+```shell
+# Gitlab labels can be imported using an id made up of `{project_id}:{group_label_id}`, e.g.
+terraform import gitlab_label.example 12345:fixme
+```

examples/resources/gitlab_label/import.sh

@@ -0,0 +1,2 @@
+# Gitlab labels can be imported using an id made up of `{project_id}:{group_label_id}`, e.g.
+terraform import gitlab_label.example 12345:fixme

internal/provider/resource_gitlab_label.go

@@ -2,15 +2,17 @@ package provider
 
 import (
 	"context"
+	"fmt"
 	"log"
+	"strconv"
+	"strings"
 
 	"github.com/hashicorp/terraform-plugin-sdk/v2/diag"
 	"github.com/hashicorp/terraform-plugin-sdk/v2/helper/schema"
 	gitlab "github.com/xanzy/go-gitlab"
 )
 
 var _ = registerResource("gitlab_label", func() *schema.Resource {
-	// lintignore: XR002 // TODO: Resolve this tfproviderlint issue
 	return &schema.Resource{
 		Description: `The ` + "`" + `gitlab_label` + "`" + ` resource allows to manage the lifecycle of a project label.
 
@@ -20,6 +22,12 @@ var _ = registerResource("gitlab_label", func() *schema.Resource {
 		ReadContext:   resourceGitlabLabelRead,
 		UpdateContext: resourceGitlabLabelUpdate,
 		DeleteContext: resourceGitlabLabelDelete,
+		// FIXME: this importer sucks a little, but we can't use a passthrough importer, because
+		//        the resource id is flawed and we don't want to break backwards-compatibility.
+		//        We cannot have the same label in two different projects as of now, ...
+		Importer: &schema.ResourceImporter{
+			StateContext: resourceGitlabLabelImporter,
+		},
 
 		Schema: map[string]*schema.Schema{
 			"project": {
@@ -130,3 +138,28 @@ func resourceGitlabLabelDelete(ctx context.Context, d *schema.ResourceData, meta
 
 	return nil
 }
+
+func resourceGitlabLabelImporter(ctx context.Context, d *schema.ResourceData, meta interface{}) ([]*schema.ResourceData, error) {
+	client := meta.(*gitlab.Client)
+	parts := strings.SplitN(d.Id(), ":", 2)
+	if len(parts) != 2 {
+		return nil, fmt.Errorf("invalid label id (should be <project ID>.<label name>): %s", d.Id())
+	}
+
+	d.SetId(parts[1])
+	project, _, err := client.Projects.GetProject(parts[0], nil)
+	if err != nil {
+		return nil, err
+	}
+
+	if err := d.Set("project", strconv.Itoa(project.ID)); err != nil {
+		return nil, err
+	}
+
+	diagnostic := resourceGitlabLabelRead(ctx, d, meta)
+	if diagnostic.HasError() {
+		return nil, fmt.Errorf("failed to read project label %s: %s", d.Id(), diagnostic[0].Summary)
+	}
+
+	return []*schema.ResourceData{d}, nil
+}

internal/provider/resource_gitlab_label_test.go

@@ -55,10 +55,37 @@ func TestAccGitlabLabel_basic(t *testing.T) {
 					}),
 				),
 			},
+			// Verify Import
+			{
+				ResourceName:      "gitlab_label.fixme",
+				ImportStateIdFunc: getLabelImportID("gitlab_label.fixme"),
+				ImportState:       true,
+				ImportStateVerify: true,
+			},
 		},
 	})
 }
 
+func getLabelImportID(n string) resource.ImportStateIdFunc {
+	return func(s *terraform.State) (string, error) {
+		rs, ok := s.RootModule().Resources[n]
+		if !ok {
+			return "", fmt.Errorf("Not Found: %s", n)
+		}
+
+		labelID := rs.Primary.ID
+		if labelID == "" {
+			return "", fmt.Errorf("No label key ID is set")
+		}
+		projectID := rs.Primary.Attributes["project"]
+		if projectID == "" {
+			return "", fmt.Errorf("No project ID is set")
+		}
+
+		return fmt.Sprintf("%s:%s", projectID, labelID), nil
+	}
+}
+
 func testAccCheckGitlabLabelExists(n string, label *gitlab.Label) resource.TestCheckFunc {
 	return func(s *terraform.State) error {
 		rs, ok := s.RootModule().Resources[n]