feat: added new variable use_default_backup_encryption_key. This now means it is possible to have KMS encryption for your primary instance, and use the default encryption on the backup instance (#233)

Co-authored-by: Andrej <[email protected]>

Author: akocbek

README.md

@@ -76,7 +76,7 @@ You need the following permissions to run this module.
 | <a name="input_access_tags"></a> [access\_tags](#input\_access\_tags) | A list of access tags to apply to the MongoDB instance created by the module, see https://cloud.ibm.com/docs/account?topic=account-access-tags-tutorial for more details | `list(string)` | `[]` | no |
 | <a name="input_admin_pass"></a> [admin\_pass](#input\_admin\_pass) | The password for the database administrator. If the admin password is null then the admin user ID cannot be accessed. More users can be specified in a user block. The admin password must be in the range of 10-32 characters. | `string` | `null` | no |
 | <a name="input_auto_scaling"></a> [auto\_scaling](#input\_auto\_scaling) | Optional rules to allow the database to increase resources in response to usage. Only a single autoscaling block is allowed. Make sure you understand the effects of autoscaling, especially for production environments. See https://cloud.ibm.com/docs/databases-for-mongodb?topic=databases-for-mongodb-autoscaling&interface=cli#autoscaling-considerations in the IBM Cloud Docs. | <pre>object({<br>    disk = object({<br>      capacity_enabled             = optional(bool, false)<br>      free_space_less_than_percent = optional(number, 10)<br>      io_above_percent             = optional(number, 90)<br>      io_enabled                   = optional(bool, false)<br>      io_over_period               = optional(string, "15m")<br>      rate_increase_percent        = optional(number, 10)<br>      rate_limit_mb_per_member     = optional(number, 3670016)<br>      rate_period_seconds          = optional(number, 900)<br>      rate_units                   = optional(string, "mb")<br>    })<br>    memory = object({<br>      io_above_percent         = optional(number, 90)<br>      io_enabled               = optional(bool, false)<br>      io_over_period           = optional(string, "15m")<br>      rate_increase_percent    = optional(number, 10)<br>      rate_limit_mb_per_member = optional(number, 114688)<br>      rate_period_seconds      = optional(number, 900)<br>      rate_units               = optional(string, "mb")<br>    })<br>  })</pre> | `null` | no |
-| <a name="input_backup_encryption_key_crn"></a> [backup\_encryption\_key\_crn](#input\_backup\_encryption\_key\_crn) | The CRN of a Key Protect key that you want to use for encrypting the disk that holds deployment backups. Only used if var.kms\_encryption\_enabled is set to true. BYOK for backups is available only in US regions us-south and us-east, and in eu-de. Only keys in the us-south and eu-de are durable to region failures. To ensure that your backups are available even if a region failure occurs, use a key from us-south or eu-de. Hyper Protect Crypto Services for IBM Cloud Databases backups is not currently supported. If no value is passed here, the value passed for the 'kms\_key\_crn' variable is used. And if a HPCS value is passed for var.kms\_key\_crn, the database backup encryption uses the default encryption keys. | `string` | `null` | no |
+| <a name="input_backup_encryption_key_crn"></a> [backup\_encryption\_key\_crn](#input\_backup\_encryption\_key\_crn) | The CRN of a Key Protect key that you want to use for encrypting the disk that holds deployment backups. Only used if var.kms\_encryption\_enabled is set to true. BYOK for backups is available only in US regions us-south and us-east, and in eu-de. Only keys in the us-south and eu-de are durable to region failures. To ensure that your backups are available even if a region failure occurs, use a key from us-south or eu-de. Hyper Protect Crypto Services for IBM Cloud Databases backups is not currently supported. If no value is passed here, the value passed for the 'kms\_key\_crn' variable is used, unless 'use\_default\_backup\_encryption\_key' is set to 'true'. And if a HPCS value is passed for var.kms\_key\_crn, the database backup encryption uses the default encryption keys. | `string` | `null` | no |
 | <a name="input_cbr_rules"></a> [cbr\_rules](#input\_cbr\_rules) | (Optional, list) List of CBR rules to create | <pre>list(object({<br>    description = string<br>    account_id  = string<br>    rule_contexts = list(object({<br>      attributes = optional(list(object({<br>        name  = string<br>        value = string<br>    }))) }))<br>    enforcement_mode = string<br>  }))</pre> | `[]` | no |
 | <a name="input_cpu_count"></a> [cpu\_count](#input\_cpu\_count) | Allocated dedicated CPU per member. For shared CPU, set to 0. For more information, see https://cloud.ibm.com/docs/databases-for-mongodb?topic=databases-for-mongodb-pricing#mongodb-scale-member | `number` | `0` | no |
 | <a name="input_disk_mb"></a> [disk\_mb](#input\_disk\_mb) | Allocated disk per member. For more information, see https://cloud.ibm.com/docs/databases-for-mongodb?topic=databases-for-mongodb-pricing#mongodb-scale-member | `number` | `10240` | no |
@@ -95,6 +95,7 @@ You need the following permissions to run this module.
 | <a name="input_service_credential_names"></a> [service\_credential\_names](#input\_service\_credential\_names) | Map of name, role for service credentials that you want to create for the database | `map(string)` | `{}` | no |
 | <a name="input_skip_iam_authorization_policy"></a> [skip\_iam\_authorization\_policy](#input\_skip\_iam\_authorization\_policy) | Set to true to skip the creation of an IAM authorization policy that permits all MongoDB database instances in the resource group to read the encryption key from the KMS instance. If set to false, pass in a value for the KMS instance in the existing\_kms\_instance\_guid variable. In addition, no policy is created if var.kms\_encryption\_enabled is set to false. | `bool` | `false` | no |
 | <a name="input_tags"></a> [tags](#input\_tags) | Optional list of tags to be added to the MongoDB instance. | `list(any)` | `[]` | no |
+| <a name="input_use_default_backup_encryption_key"></a> [use\_default\_backup\_encryption\_key](#input\_use\_default\_backup\_encryption\_key) | Set to true to use default ICD randomly generated keys. | `bool` | `false` | no |
 | <a name="input_users"></a> [users](#input\_users) | A list of users that you want to create on the database. Multiple blocks are allowed. The user password must be in the range of 10-32 characters. Be warned that in most case using IAM service credentials (via the var.service\_credential\_names) is sufficient to control access to the MongoDB instance. This blocks creates native MongoDB database users, more info on that can be found here https://cloud.ibm.com/docs/databases-for-mongodb?topic=databases-for-mongodb-user-management&interface=ui | <pre>list(object({<br>    name     = string<br>    password = string # pragma: allowlist secret<br>    type     = string # "type" is required to generate the connection string for the outputs.<br>    role     = optional(string)<br>  }))</pre> | `[]` | no |
 
 ### Outputs

main.tf

@@ -10,10 +10,12 @@ locals {
   validate_kms_vars = var.kms_encryption_enabled && var.kms_key_crn == null && var.backup_encryption_key_crn == null ? tobool("When setting var.kms_encryption_enabled to true, a value must be passed for var.kms_key_crn and/or var.backup_encryption_key_crn") : true
   # tflint-ignore: terraform_unused_declarations
   validate_auth_policy = var.kms_encryption_enabled && var.skip_iam_authorization_policy == false && var.existing_kms_instance_guid == null ? tobool("When var.skip_iam_authorization_policy is set to false, and var.kms_encryption_enabled to true, a value must be passed for var.existing_kms_instance_guid in order to create the auth policy.") : true
+  # tflint-ignore: terraform_unused_declarations
+  validate_backup_key = var.backup_encryption_key_crn != null && var.use_default_backup_encryption_key == true ? tobool("When passing a value for 'backup_encryption_key_crn' you cannot set 'use_default_backup_encryption_key' to 'true'") : true
 
   # If no value passed for 'backup_encryption_key_crn' use the value of 'kms_key_crn'. If this is a HPCS key (which is not currently supported for backup encryption), default to 'null' meaning encryption is done using randomly generated keys
   # More info https://cloud.ibm.com/docs/cloud-databases?topic=cloud-databases-hpcs
-  backup_encryption_key_crn = var.backup_encryption_key_crn != null ? var.backup_encryption_key_crn : (can(regex(".*kms.*", var.kms_key_crn)) ? var.kms_key_crn : null)
+  backup_encryption_key_crn = var.use_default_backup_encryption_key == true ? null : (var.backup_encryption_key_crn != null ? var.backup_encryption_key_crn : (can(regex(".*kms.*", var.kms_key_crn)) ? var.kms_key_crn : null))
 
   # Determine if auto scaling is enabled
   auto_scaling_enabled = var.auto_scaling == null ? [] : [1]

module-metadata.json

@@ -47,7 +47,7 @@
     "backup_encryption_key_crn": {
       "name": "backup_encryption_key_crn",
       "type": "string",
-      "description": "The CRN of a Key Protect key that you want to use for encrypting the disk that holds deployment backups. Only used if var.kms_encryption_enabled is set to true. BYOK for backups is available only in US regions us-south and us-east, and in eu-de. Only keys in the us-south and eu-de are durable to region failures. To ensure that your backups are available even if a region failure occurs, use a key from us-south or eu-de. Hyper Protect Crypto Services for IBM Cloud Databases backups is not currently supported. If no value is passed here, the value passed for the 'kms_key_crn' variable is used. And if a HPCS value is passed for var.kms_key_crn, the database backup encryption uses the default encryption keys.",
+      "description": "The CRN of a Key Protect key that you want to use for encrypting the disk that holds deployment backups. Only used if var.kms_encryption_enabled is set to true. BYOK for backups is available only in US regions us-south and us-east, and in eu-de. Only keys in the us-south and eu-de are durable to region failures. To ensure that your backups are available even if a region failure occurs, use a key from us-south or eu-de. Hyper Protect Crypto Services for IBM Cloud Databases backups is not currently supported. If no value is passed here, the value passed for the 'kms_key_crn' variable is used, unless 'use_default_backup_encryption_key' is set to 'true'. And if a HPCS value is passed for var.kms_key_crn, the database backup encryption uses the default encryption keys.",
       "pos": {
         "filename": "variables.tf",
         "line": 193
@@ -67,7 +67,7 @@
       ],
       "pos": {
         "filename": "variables.tf",
-        "line": 219
+        "line": 225
       }
     },
     "cpu_count": {
@@ -115,7 +115,7 @@
       ],
       "pos": {
         "filename": "variables.tf",
-        "line": 209
+        "line": 215
       },
       "immutable": true,
       "computed": true
@@ -278,7 +278,7 @@
       "default": false,
       "pos": {
         "filename": "variables.tf",
-        "line": 203
+        "line": 209
       }
     },
     "tags": {
@@ -294,6 +294,16 @@
         "line": 67
       }
     },
+    "use_default_backup_encryption_key": {
+      "name": "use_default_backup_encryption_key",
+      "type": "bool",
+      "description": "Set to true to use default ICD randomly generated keys.",
+      "default": false,
+      "pos": {
+        "filename": "variables.tf",
+        "line": 203
+      }
+    },
     "users": {
       "name": "users",
       "type": "list(object({\n    name     = string\n    password = string # pragma: allowlist secret\n    type     = string # \"type\" is required to generate the connection string for the outputs.\n    role     = optional(string)\n  }))",
@@ -435,7 +445,7 @@
       },
       "pos": {
         "filename": "main.tf",
-        "line": 47
+        "line": 49
       }
     },
     "ibm_iam_authorization_policy.kms_policy": {
@@ -453,7 +463,7 @@
       },
       "pos": {
         "filename": "main.tf",
-        "line": 30
+        "line": 32
       }
     },
     "ibm_resource_key.service_credentials": {
@@ -468,7 +478,7 @@
       },
       "pos": {
         "filename": "main.tf",
-        "line": 181
+        "line": 183
       }
     },
     "ibm_resource_tag.mongodb_tag": {
@@ -484,7 +494,7 @@
       },
       "pos": {
         "filename": "main.tf",
-        "line": 130
+        "line": 132
       }
     },
     "time_sleep.wait_for_authorization_policy": {
@@ -496,7 +506,7 @@
       },
       "pos": {
         "filename": "main.tf",
-        "line": 41
+        "line": 43
       }
     }
   },
@@ -516,7 +526,7 @@
       },
       "pos": {
         "filename": "main.tf",
-        "line": 209
+        "line": 211
       }
     }
   },
@@ -595,7 +605,7 @@
       },
       "pos": {
         "filename": "main.tf",
-        "line": 141
+        "line": 143
       }
     }
   }

variables.tf

@@ -192,14 +192,20 @@ variable "kms_key_crn" {
 
 variable "backup_encryption_key_crn" {
   type        = string
-  description = "The CRN of a Key Protect key that you want to use for encrypting the disk that holds deployment backups. Only used if var.kms_encryption_enabled is set to true. BYOK for backups is available only in US regions us-south and us-east, and in eu-de. Only keys in the us-south and eu-de are durable to region failures. To ensure that your backups are available even if a region failure occurs, use a key from us-south or eu-de. Hyper Protect Crypto Services for IBM Cloud Databases backups is not currently supported. If no value is passed here, the value passed for the 'kms_key_crn' variable is used. And if a HPCS value is passed for var.kms_key_crn, the database backup encryption uses the default encryption keys."
+  description = "The CRN of a Key Protect key that you want to use for encrypting the disk that holds deployment backups. Only used if var.kms_encryption_enabled is set to true. BYOK for backups is available only in US regions us-south and us-east, and in eu-de. Only keys in the us-south and eu-de are durable to region failures. To ensure that your backups are available even if a region failure occurs, use a key from us-south or eu-de. Hyper Protect Crypto Services for IBM Cloud Databases backups is not currently supported. If no value is passed here, the value passed for the 'kms_key_crn' variable is used, unless 'use_default_backup_encryption_key' is set to 'true'. And if a HPCS value is passed for var.kms_key_crn, the database backup encryption uses the default encryption keys."
   default     = null
   validation {
     condition     = var.backup_encryption_key_crn == null ? true : length(regexall("^crn:v1:bluemix:public:kms:(us-south|us-east|eu-de):a/[[:xdigit:]]{32}:[[:xdigit:]]{8}-[[:xdigit:]]{4}-[[:xdigit:]]{4}-[[:xdigit:]]{4}-[[:xdigit:]]{12}:key:[[:xdigit:]]{8}-[[:xdigit:]]{4}-[[:xdigit:]]{4}-[[:xdigit:]]{4}-[[:xdigit:]]{12}$", var.backup_encryption_key_crn)) > 0
     error_message = "Valid values for backup_encryption_key_crn is null or a Key Protect key CRN from us-south, us-east or eu-de"
   }
 }
 
+variable "use_default_backup_encryption_key" {
+  type        = bool
+  description = "Set to true to use default ICD randomly generated keys."
+  default     = false
+}
+
 variable "skip_iam_authorization_policy" {
   type        = bool
   description = "Set to true to skip the creation of an IAM authorization policy that permits all MongoDB database instances in the resource group to read the encryption key from the KMS instance. If set to false, pass in a value for the KMS instance in the existing_kms_instance_guid variable. In addition, no policy is created if var.kms_encryption_enabled is set to false."