feat: Support GCP impersonation (#94)

Introduce new parameter `streamnative_org_id` which is required to grant
permissions of GCP project for impersonation

modules/gcp/vendor-access/README.md

@@ -34,8 +34,9 @@ provider "google" {
 }
 
 module "sn_managed_cloud" {
-  source = "github.com/streamnative/terraform-managed-cloud//modules/gcp/vendor-access?ref=v3.7.0"
+  source = "github.com/streamnative/terraform-managed-cloud//modules/gcp/vendor-access?ref=v3.15.0"
   project = "<YOUR_PROJECT>"
+  streamnative_org_id = "<YOUR_ORG_ID>"
 }
 ```
 
@@ -523,7 +524,8 @@ No modules.
 |------|-------------|------|---------|:--------:|
 | <a name="input_extra_google_services"></a> [extra\_google\_services](#input\_extra\_google\_services) | Extra google API services need to be enabled. | `list(string)` | `[]` | no |
 | <a name="input_project"></a> [project](#input\_project) | The project id of the target project | `string` | n/a | yes |
-| <a name="input_roles"></a> [roles](#input\_roles) | The role list will be associated with StreamNative GSA. | `list(string)` | <pre>[<br>  "roles/editor",<br>  "roles/compute.admin",<br>  "roles/compute.loadBalancerAdmin",<br>  "roles/compute.networkAdmin",<br>  "roles/container.admin",<br>  "roles/dns.admin",<br>  "roles/storage.admin",<br>  "roles/iam.serviceAccountAdmin",<br>  "roles/iam.workloadIdentityPoolAdmin",<br>  "roles/resourcemanager.projectIamAdmin"<br>]</pre> | no |
+| <a name="input_roles"></a> [roles](#input\_roles) | The role list will be associated with StreamNative GSA. | `list(string)` | <pre>[<br>  "roles/editor",<br>  "roles/cloudkms.admin",<br>  "roles/compute.admin",<br>  "roles/compute.loadBalancerAdmin",<br>  "roles/compute.networkAdmin",<br>  "roles/container.admin",<br>  "roles/dns.admin",<br>  "roles/storage.admin",<br>  "roles/iam.serviceAccountAdmin",<br>  "roles/iam.workloadIdentityPoolAdmin",<br>  "roles/resourcemanager.projectIamAdmin"<br>]</pre> | no |
+| <a name="input_streamnative_org_id"></a> [streamnative\_org\_id](#input\_streamnative\_org\_id) | Your Organization ID within StreamNative Cloud, used as name of impersonation GSA in your project. This will be the organization ID in the StreamNative console, e.g. "o-xhopj". | `string` | `""` | no |
 | <a name="input_streamnative_support_access_gsa"></a> [streamnative\_support\_access\_gsa](#input\_streamnative\_support\_access\_gsa) | The GSA will be used by StreamnNative support team. | `list(string)` | <pre>[<br>  "[email protected]"<br>]</pre> | no |
 | <a name="input_streamnative_vendor_access_gsa"></a> [streamnative\_vendor\_access\_gsa](#input\_streamnative\_vendor\_access\_gsa) | The GSA will be used by StreamnNative cloud. | `list(string)` | <pre>[<br>  "[email protected]",<br>  "[email protected]"<br>]</pre> | no |
 
@@ -533,3 +535,4 @@ No modules.
 |------|-------------|
 | <a name="output_google_services"></a> [google\_services](#output\_google\_services) | Enabled google services. |
 | <a name="output_iam_bindings"></a> [iam\_bindings](#output\_iam\_bindings) | Configured iam policies. |
+| <a name="output_impersonation_iam_bindings"></a> [impersonation\_iam\_bindings](#output\_impersonation\_iam\_bindings) | Configured iam policies for impersonation. |

modules/gcp/vendor-access/common.tf

@@ -31,6 +31,16 @@ variable "streamnative_vendor_access_gsa" {
   description = "The GSA will be used by StreamnNative cloud."
 }
 
+variable "streamnative_org_id" {
+  default     = ""
+  type        = string
+  description = "Your Organization ID within StreamNative Cloud, used as name of impersonation GSA in your project. This will be the organization ID in the StreamNative console, e.g. \"o-xhopj\"."
+  validation {
+    condition = length(var.streamnative_org_id) <= 18
+    error_message = "The organization ID must not exceed 18 characters. If you reach this limit, please contact StreamNative support."
+  }
+}
+
 variable "streamnative_support_access_gsa" {
   default     = ["[email protected]"]
   type        = list(string)

modules/gcp/vendor-access/docs/main.tf

@@ -3,6 +3,7 @@ provider "google" {
 }
 
 module "sn_managed_cloud" {
-  source = "github.com/streamnative/terraform-managed-cloud//modules/gcp/vendor-access?ref=v3.7.0"
+  source = "github.com/streamnative/terraform-managed-cloud//modules/gcp/vendor-access?ref=v3.15.0"
   project = "<YOUR_PROJECT>"
+  streamnative_org_id = "<YOUR_ORG_ID>"
 }

modules/gcp/vendor-access/main.tf

@@ -1,13 +1,4 @@
 locals {
-  streamnative_gsa = concat(var.streamnative_vendor_access_gsa, var.streamnative_support_access_gsa)
-  iam_bindings = flatten([
-    for role in var.roles : [
-      for gsa in local.streamnative_gsa : {
-        role : role,
-        member : format("serviceAccount:%s", gsa),
-      }
-    ]
-  ])
   google_services = concat([
     "autoscaling.googleapis.com",
     "cloudresourcemanager.googleapis.com",
@@ -31,23 +22,86 @@ resource "google_project_service" "gcp_apis" {
   service            = local.google_services[count.index]
 }
 
+locals {
+  is_impersonation_enabled = var.streamnative_org_id != ""
+  streamnative_gsa         = concat(var.streamnative_vendor_access_gsa, var.streamnative_support_access_gsa)
+}
+
+# Grant permissions directly to the StreamNative Cloud service account
+locals {
+  iam_bindings = local.is_impersonation_enabled ? [] : flatten([
+    for role in var.roles : [
+      for gsa in local.streamnative_gsa : {
+        role : role,
+        member : format("serviceAccount:%s", gsa),
+      }
+    ]
+  ])
+}
+
 resource "google_project_iam_member" "sn_access" {
-  for_each = {
-    for index, binding in local.iam_bindings :
-    index => binding
-  }
+  count = length(local.iam_bindings)
   project    = var.project
-  role       = each.value.role
-  member     = each.value.member
+  role       = local.iam_bindings[count.index].role
+  member     = local.iam_bindings[count.index].member
   depends_on = [google_project_service.gcp_apis]
 }
 
+# Grant permissions to the project service account that will be impersonated by StreamNative Cloud service account
+locals {
+  streamnative_bootstrap_gsa_name = format("snbootstrap-%s", var.streamnative_org_id)
+  streamnative_bootstrap_roles    = local.is_impersonation_enabled ? var.roles : []
+  impersonation_roles = [
+    "roles/iam.serviceAccountUser",
+    "roles/iam.serviceAccountAdmin",
+    "roles/iam.serviceAccountTokenCreator",
+  ]
+  impersonation_iam_bindings = local.is_impersonation_enabled ? flatten([
+    for role in local.impersonation_roles : [
+      for gsa in local.streamnative_gsa : {
+        role : role,
+        member : format("serviceAccount:%s", gsa),
+      }
+    ]
+  ]) : []
+
+}
+resource "google_service_account" "sn_bootstrap" {
+  count        = local.is_impersonation_enabled ? 1 : 0
+  account_id   = local.streamnative_bootstrap_gsa_name
+  project      = var.project
+  display_name = "StreamNative Bootstrap GSA that will be impersonated by StreamNative Cloud Control Plane."
+  depends_on   = [google_project_service.gcp_apis]
+}
+
+resource "google_project_iam_member" "sn_bootstrap" {
+  count      = length(local.streamnative_bootstrap_roles)
+  project    = var.project
+  role       = local.streamnative_bootstrap_roles[count.index]
+  member     = format("serviceAccount:%s", google_service_account.sn_bootstrap[0].email)
+  depends_on = [google_service_account.sn_bootstrap]
+}
+
+resource "google_service_account_iam_member" "sn_bootstrap_impersonation" {
+  count              = length(local.impersonation_iam_bindings)
+  service_account_id = google_service_account.sn_bootstrap[0].id
+  role               = local.impersonation_iam_bindings[count.index].role
+  member             = local.impersonation_iam_bindings[count.index].member
+  depends_on         = [google_service_account.sn_bootstrap]
+}
+
+
 output "google_services" {
-  value = local.google_services
+  value       = local.google_services
   description = "Enabled google services."
 }
 
 output "iam_bindings" {
-  value = local.iam_bindings
+  value       = local.iam_bindings
   description = "Configured iam policies."
 }
+
+output "impersonation_iam_bindings" {
+  value       = local.impersonation_iam_bindings
+  description = "Configured iam policies for impersonation."
+}