added the possibility to handle an existing DRG (#4)

* added the possibility to handle an existing DRG

* Updated description for region

Co-authored-by: Ali Mukadam <[email protected]>

Author: snafuz

README.adoc

@@ -36,6 +36,7 @@ It creates the following resources:
 * A DRG attached to one or more customizable VCNs 
 * An optional Remote Peering Connection (RPC)
 
+> This module can either create a new DRG or wrap around an existing one.
 
 This module is primarily meant to be reusable to create more advanced infrastructure on {uri-oci}[OCI] either manually in the OCI Console or by extending the Terraform code.
 

README.md

@@ -7,6 +7,7 @@ It creates the following resources:
 * A DRG attached to one or more customizable VCNs 
 * An optional Remote Peering Connection (RPC) 
 
+> This module can either create a new DRG or wrap around an existing one.
 
 This module is primarily meant to be reusable to create more advanced infrastructure on [OCI][OCI] either manually in the OCI Console or by extending the Terraform code.
 

drg.tf

@@ -1,12 +1,25 @@
 # Copyright (c) 2022 Oracle Corporation and/or affiliates.  All rights reserved.
 # Licensed under the Universal Permissive License v 1.0 as shown at https://oss.oracle.com/licenses/upl
 
+
 resource "oci_core_drg" "drg" {
   compartment_id = var.compartment_id
   display_name   = var.label_prefix == "none" ? var.drg_display_name : "${var.label_prefix}-${var.drg_display_name}"
 
   freeform_tags = var.freeform_tags
   defined_tags  = var.defined_tags
+
+  count = var.drg_id == null ? 1 : 0
+}
+
+data "oci_core_drgs" "drg_data" {
+  compartment_id = var.compartment_id
+
+  filter {
+    name   = "id"
+    values = [var.drg_id]
+  }
+
 }
 
 resource "oci_core_drg_attachment" "vcns" {
@@ -16,7 +29,7 @@ resource "oci_core_drg_attachment" "vcns" {
   freeform_tags = var.freeform_tags
   defined_tags  = var.defined_tags
 
-  drg_id = oci_core_drg.drg.id
+  drg_id = var.drg_id == null ? oci_core_drg.drg[0].id : var.drg_id
 
   network_details {
     id             = each.value.vcn_id                                                                          # required
@@ -32,9 +45,9 @@ resource "oci_core_drg_attachment" "vcns" {
 }
 
 resource "oci_core_remote_peering_connection" "rpc" {
-  
+
   compartment_id = var.compartment_id
-  drg_id         = oci_core_drg.drg.id
+  drg_id         = var.drg_id == null ? oci_core_drg.drg[0].id : var.drg_id
   display_name   = var.label_prefix == "none" ? "rpc_created_from_${var.drg_display_name}" : "${var.label_prefix}_rpc"
 
   freeform_tags = var.freeform_tags

outputs.tf

@@ -3,23 +3,19 @@
 
 output "drg_id" {
   description = "id of drg if it is created"
-  value       = join(",", oci_core_drg.drg[*].id)
+  value       = join(",", length(data.oci_core_drgs.drg_data.drgs) == 0 ? oci_core_drg.drg[*].id : data.oci_core_drgs.drg_data.drgs[*].id)
 }
 
-
-
 output "drg_display_name" {
   description = "display name of drg if it is created"
-  value       = join(",", oci_core_drg.drg[*].display_name)
+  value       = join(",", length(data.oci_core_drgs.drg_data.drgs) == 0 ? oci_core_drg.drg[*].display_name : data.oci_core_drgs.drg_data.drgs[*].display_name)
 }
 
-
 # Complete outputs for each resources with provider parity. Auto-updating.
 # Useful for module composition.
-
 output "drg_all_attributes" {
   description = "all attributes of created drg"
-  value       = { for k, v in oci_core_drg.drg : k => v }
+  value       = { for k, v in(length(data.oci_core_drgs.drg_data.drgs) == 0 ? oci_core_drg.drg[0] : data.oci_core_drgs.drg_data.drgs[0]) : k => v }
 }
 
 output "drg_attachment_all_attributes" {
@@ -30,8 +26,8 @@ output "drg_attachment_all_attributes" {
 output "drg_summary" {
   description = "drg information summary"
   value = {
-    (oci_core_drg.drg.display_name) = {
-      drg_id          = oci_core_drg.drg.id
+    (length(data.oci_core_drgs.drg_data.drgs) == 0 ? oci_core_drg.drg[0].display_name : data.oci_core_drgs.drg_data.drgs[0].display_name) = {
+      drg_id          = length(data.oci_core_drgs.drg_data.drgs) == 0 ? oci_core_drg.drg[0].id : data.oci_core_drgs.drg_data.drgs[*].id
       vcn_attachments = { for k, v in oci_core_drg_attachment.vcns : k => v.network_details[0].id }
 
     }
@@ -43,7 +39,6 @@ output "drg_summary" {
 }
 
 
-
 output "rpc_id" {
   description = "id of RPC if it is created"
   value       = join(",", oci_core_remote_peering_connection.rpc[*].id)

terraform.tfvars.example

@@ -24,6 +24,7 @@ defined_tags  = {}
 
 # drg parameters
 drg_display_name = "drg"
+drg_id = null
 
 # vcns to be attached
 drg_vcn_attachments = null

variables.tf

@@ -1,17 +1,13 @@
 # Copyright (c) 2022 Oracle Corporation and/or affiliates.  All rights reserved.
 # Licensed under the Universal Permissive License v 1.0 as shown at https://oss.oracle.com/licenses/upl
 
-# provider identity parameters
+# general oci parameters
 
 variable "region" {
   # List of regions: https://docs.cloud.oracle.com/iaas/Content/General/Concepts/regions.htm#ServiceAvailabilityAcrossRegions
-  description = "the OCI region where resources will be created"
+  description = "The OCI region where the DRG will be created."
   type        = string
-  default     = null
 }
-
-# general oci parameters
-
 variable "compartment_id" {
   description = "compartment id where to create all resources"
   type        = string
@@ -58,6 +54,12 @@ variable "drg_vcn_attachments" {
   default     = null
 }
 
+variable "drg_id" {
+  description = "ID of an external created DRG"
+  type        = string
+  default     = null
+}
+
 # rpc parameters
 variable "create_rpc" {
   description = "Whether to create Remote Peering Connection. If set to true, creates an RPC"
@@ -67,8 +69,8 @@ variable "create_rpc" {
 
 variable "rpc_acceptor_id" {
   description = "the ID of the remote RPC"
-  type = string
-  default = null
+  type        = string
+  default     = null
 }
 variable "rpc_acceptor_region" {
   # List of regions: https://docs.cloud.oracle.com/iaas/Content/General/Concepts/regions.htm#ServiceAvailabilityAcrossRegions