From d07a9883a77f935f6af8fe925c71e431af9190fb Mon Sep 17 00:00:00 2001
From: Ben Weintraub <benweint@gmail.com>
Date: Mon, 26 Apr 2021 16:25:03 -0700
Subject: [PATCH] Support importing existing Kafka clusters (fixes #64) (#74)

This change should address the issue reported in #64 wherein it's not currently possible to import existing Kafka clusters.

The issue is that the read function for clusters requires both the cluster ID and the containing environment ID, which means that using the pass-through state importer function doesn't work.

I've addressed this by allowing clusters to be imported by passing an import ID of the form `<environment ID>/<cluster ID>`.
---
 README.md                             |  8 ++++++++
 ccloud/resource_kafka_cluster.go      | 20 +++++++++++++++++++-
 ccloud/resource_kafka_cluster_test.go | 13 +++++++++++++
 go.mod                                |  2 +-
 4 files changed, 41 insertions(+), 2 deletions(-)

diff --git a/README.md b/README.md
index 54896f2..b29bee9 100644
--- a/README.md
+++ b/README.md
@@ -114,6 +114,14 @@ output "secret" {
 }
 ```
 
+## Importing existing resources
+
+This provider supports importing existing Confluent Cloud resources via [`terraform import`][3].
+
+Most resource types use the import IDs returned by the [`ccloud`][4] CLI, with the exception of clusters, which expect an import ID of the form `<environment ID>/<cluster ID>`.
+
 [1]: https://www.terraform.io
 [2]: https://confluent.cloud
+[3]: https://www.terraform.io/docs/cli/import/index.html
+[4]: https://docs.confluent.io/ccloud-cli/current/index.html
 [third-party-plugins]: https://www.terraform.io/docs/configuration/providers.html#third-party-plugins
diff --git a/ccloud/resource_kafka_cluster.go b/ccloud/resource_kafka_cluster.go
index 9cc9d22..d77e499 100644
--- a/ccloud/resource_kafka_cluster.go
+++ b/ccloud/resource_kafka_cluster.go
@@ -20,7 +20,7 @@ func kafkaClusterResource() *schema.Resource {
 		ReadContext:   clusterRead,
 		DeleteContext: clusterDelete,
 		Importer: &schema.ResourceImporter{
-			StateContext: schema.ImportStatePassthroughContext,
+			StateContext: clusterImport,
 		},
 		Schema: map[string]*schema.Schema{
 			"name": {
@@ -243,6 +243,24 @@ func clusterDelete(ctx context.Context, d *schema.ResourceData, meta interface{}
 	return diags
 }
 
+func clusterImport(_ context.Context, d *schema.ResourceData, _ interface{}) ([]*schema.ResourceData, error) {
+	envIDAndClusterID := d.Id()
+	parts := strings.Split(envIDAndClusterID, "/")
+
+	var err error
+	if len(parts) != 2 {
+		return nil, fmt.Errorf("invalid format for cluster import: expected '<env ID>/<cluster ID>'")
+	}
+
+	d.SetId(parts[1])
+	err = d.Set("environment_id", parts[0])
+	if err != nil {
+		return nil, err
+	}
+
+	return []*schema.ResourceData{d}, nil
+}
+
 func clusterRead(ctx context.Context, d *schema.ResourceData, meta interface{}) diag.Diagnostics {
 	c := meta.(*ccloud.Client)
 	accountID := d.Get("environment_id").(string)
diff --git a/ccloud/resource_kafka_cluster_test.go b/ccloud/resource_kafka_cluster_test.go
index baf6ed3..d47e4bd 100644
--- a/ccloud/resource_kafka_cluster_test.go
+++ b/ccloud/resource_kafka_cluster_test.go
@@ -5,6 +5,8 @@ import (
 	"os"
 	"testing"
 
+	"github.com/hashicorp/terraform-plugin-sdk/v2/terraform"
+
 	"github.com/hashicorp/go-uuid"
 	r "github.com/hashicorp/terraform-plugin-sdk/v2/helper/resource"
 	"github.com/hashicorp/terraform-plugin-sdk/v2/helper/schema"
@@ -38,6 +40,17 @@ func TestAcc_BasicCluster(t *testing.T) {
 			{
 				Config: fmt.Sprintf(testResourceCluster_noConfig, u, u),
 			},
+			{
+				ResourceName: "confluentcloud_kafka_cluster.test",
+				ImportState:  true,
+				ImportStateIdFunc: func(state *terraform.State) (string, error) {
+					resources := state.RootModule().Resources
+					clusterId := resources["confluentcloud_kafka_cluster.test"].Primary.ID
+					envId := resources["confluentcloud_environment.test"].Primary.ID
+					return envId + "/" + clusterId, nil
+				},
+				ImportStateVerify: true,
+			},
 		},
 	})
 }
diff --git a/go.mod b/go.mod
index ad4efcc..4411a1c 100644
--- a/go.mod
+++ b/go.mod
@@ -14,7 +14,7 @@ require (
 	github.com/go-resty/resty/v2 v2.2.0 // indirect
 	github.com/hashicorp/errwrap v1.1.0 // indirect
 	github.com/hashicorp/go-multierror v1.1.0 // indirect
-	github.com/hashicorp/go-uuid v1.0.2 // indirect
+	github.com/hashicorp/go-uuid v1.0.2
 	github.com/hashicorp/terraform-plugin-docs v0.3.0
 	github.com/hashicorp/terraform-plugin-sdk/v2 v2.4.4
 	github.com/hashicorp/yamux v0.0.0-20200609203250-aecfd211c9ce // indirect