Terraform boolean variable true - based on mapped values - database

Question

Expected Behaviour
I would like to make a boolean variable 'var.enable_retention_policy' true based on the output of mapped value 'var.ds_allmetrics_retention_days'
Actual Behaviour
throws error (see Error output)
Error Output
Error: Inconsistent conditional result types
on ..\db\main.tf line 37, in module "diagnostic_mssql_db":
37: "WorkloadManagement" = var.workload_management > 0 ? var.workload_management : var.enable_retention_policy
The true and false result expressions must have consistent types. The given
expressions are number and bool, respectively.
Terraform (and AzureRM Provider) Version
Affected Resource(s)
azurerm_v2.41.0
terraform v0.13.0
Terraform Configuration Files
Main.tf
data "azurerm_storage_account" "storage_account" {
name = var.storage_account
resource_group_name = var.sa_resource_group
}
resource "azurerm_monitor_diagnostic_setting" "diagsetting" {
name = var.target_resource_name
target_resource_id = var.target_resource_id
storage_account_id = data.azurerm_storage_account.storage_account.id
dynamic "log" {
for_each = keys(var.ds_log_api_endpoints)
content {
category = log.value
enabled = true
retention_policy {
enabled = var.enable_retention_policy
days = lookup(var.ds_log_api_endpoints, log.value, 0)
}
}
}
dynamic "metric" {
for_each = keys(var.ds_allmetrics_retention_days)
content {
category = metric.value
retention_policy {
enabled = var.enable_retention_policy
days = lookup(var.ds_allmetrics_retention_days, metric.value, 0)
}
}
}
}
Variables.tf
# boolean variable
variable "enable_retention_policy" {
type = bool
description = "toggle on/off the retention policy for the metric"
default = false
}
# mapped values
variable "ds_allmetrics_retention_days" {
type = map
description = "Azure monitor diagnostic setting category for retention in days of target resource."
default = {}
}
Module call
module "diagnostic_mssql_db" {
source = "github.com/faraday23/terraform-azurerm-monitor-diagnostic-setting.git"
storage_account = var.storage_account
sa_resource_group = var.sa_resource_group
target_resource_id = azurerm_mssql_database.db.id
target_resource_name = azurerm_mssql_database.db.name
enable_retention_policy = var.enable_retention_policy
ds_log_api_endpoints = { "AutomaticTuning" = var.automatic_tuning > 0 ? var.automatic_tuning : var.enable_retention_policy,
"Blocks" = var.blocks > 0 ? var.blocks : var.enable_retention_policy,
"DatabaseWaitStatistics" = var.database_wait_statistics > 0 ? var.database_wait_statistics : var.enable_retention_policy,
"Deadlocks" = var.deadlocks > 0 ? var.deadlocks : var.enable_retention_policy,
"Errors" = var.error_log > 0 ? var.error_log : var.enable_retention_policy,
"Timeouts" = var.timeouts > 0 ? var.timeouts : var.enable_retention_policy,
"QueryStoreRuntimeStatistics" = var.query_store_runtime_statistics > 0 ? var.query_store_runtime_statistics : var.enable_retention_policy,
"QueryStoreWaitStatistics" = var.query_store_wait_statistics > 0 ? var.query_store_wait_statistics : var.enable_retention_policy,
"SQLInsights" = var.sql_insights > 0 ? var.sql_insights : var.enable_retention_policy
}
ds_allmetrics_retention_days = { "Basic" = var.basic > 0 ? var.basic : var.enable_retention_policy,
"InstanceAndAppAdvanced" = var.instance_and_app_advanced > 0 ? var.instance_and_app_advanced : var.enable_retention_policy,
"WorkloadManagement" = var.workload_management > 0 ? var.workload_management : var.enable_retention_policy
}
}

Answer 1

The error message indicates that the issue is with WorkloadManagement. In your case you have mixture of bool and int which is incorrect. Conditional Expressions must be of same type:
The two result values may be of any type, but they must both be of the same type so that Terraform can determine what type the whole conditional expression will return without knowing the condition value.
Thus, you can use tonumber to change bool to int:
Update based on Martin comment
The original answer used tonumber(var.enable_retention_policy) which was incorrect, as you can't convert bool to number. To correct answer is then:
"WorkloadManagement" = (var.workload_management > 0
? var.workload_management
: (var.enable_retention_policy ? 1 : 0))