Try another approach. I hate hcl

Author: OscarVanL

modules/mysql/main.tf

@@ -162,10 +162,10 @@ resource "google_sql_database_instance" "default" {
             allowed_consumer_projects = ip_configuration.value.psc_allowed_consumer_projects
 
             dynamic "psc_auto_connections" {
-              for_each = ip_configuration.value.psc_auto_connections
+              for_each = lookup(ip_configuration.value, "psc_auto_connections", [])
               content {
-                consumer_network            = each.value.consumer_network
-                consumer_service_project_id = each.value.consumer_service_project_id
+                consumer_network            = psc_auto_connections.value.consumer_network
+                consumer_service_project_id = psc_auto_connections.value.consumer_service_project_id
               }
             }
           }

modules/mysql/read_replica.tf

@@ -94,10 +94,10 @@ resource "google_sql_database_instance" "replicas" {
             allowed_consumer_projects = ip_configuration.value.psc_allowed_consumer_projects
 
             dynamic "psc_auto_connections" {
-              for_each = ip_configuration.value.psc_auto_connections
+              for_each = lookup(ip_configuration.value, "psc_auto_connections", [])
               content {
-                consumer_network            = each.value.consumer_network
-                consumer_service_project_id = each.value.consumer_service_project_id
+                consumer_network            = psc_auto_connections.value.consumer_network
+                consumer_service_project_id = psc_auto_connections.value.consumer_service_project_id
               }
             }
           }

modules/postgresql/main.tf

@@ -147,10 +147,10 @@ resource "google_sql_database_instance" "default" {
             allowed_consumer_projects = ip_configuration.value.psc_allowed_consumer_projects
 
             dynamic "psc_auto_connections" {
-              for_each = ip_configuration.value.psc_auto_connections
+              for_each = lookup(ip_configuration.value, "psc_auto_connections", [])
               content {
-                consumer_network            = each.value.consumer_network
-                consumer_service_project_id = each.value.consumer_service_project_id
+                consumer_network            = psc_auto_connections.value.consumer_network
+                consumer_service_project_id = psc_auto_connections.value.consumer_service_project_id
               }
             }
           }

modules/postgresql/read_replica.tf

@@ -69,10 +69,10 @@ resource "google_sql_database_instance" "replicas" {
             allowed_consumer_projects = ip_configuration.value.psc_enabled ? ip_configuration.value.psc_allowed_consumer_projects : []
 
             dynamic "psc_auto_connections" {
-              for_each = ip_configuration.value.psc_auto_connections
+              for_each = lookup(ip_configuration.value, "psc_auto_connections", [])
               content {
-                consumer_network            = each.value.consumer_network
-                consumer_service_project_id = each.value.consumer_service_project_id
+                consumer_network            = psc_auto_connections.value.consumer_network
+                consumer_service_project_id = psc_auto_connections.value.consumer_service_project_id
               }
             }
           }