Setting alerts but getting - "has for_each set, its attributes must be accessed on specific instances"

Terraform Providers
1

Hello Team,

I’m creating a test env in Azure using terraform and all is working so far except my alerts (deploying Azure Container Apps). Would appreciate some help and guidance:

aca.tf

resource "azapi_resource" "aca_env" {
  type      = "Microsoft.App/managedEnvironments@2022-10-01"
  parent_id = azurerm_resource_group.rg.id
  location  = azurerm_resource_group.rg.location
  name      = "aca-env-terraform"
  tags      = local.tags
  
  body   = jsonencode({
    properties = {
      appLogsConfiguration = {
        destination               = "log-analytics"
        logAnalyticsConfiguration = {
          customerId = azurerm_log_analytics_workspace.law.workspace_id
          sharedKey  = azurerm_log_analytics_workspace.law.primary_shared_key
        }
      }
    }
 })
}

resource "azapi_resource" "aca" {
  for_each  = { for ca in var.container_apps: ca.name => ca}
  type      = "Microsoft.App/containerApps@2022-10-01"
  parent_id = azurerm_resource_group.rg.id
  location  = azurerm_resource_group.rg.location
  name      = each.value.name
  
  body = jsonencode({
    properties: {
      managedEnvironmentId = azapi_resource.aca_env.id
      configuration = {
        ingress = {
          external = each.value.ingress_enabled
          targetPort = each.value.ingress_enabled?each.value.containerPort: null
        }
      }
      template = {
        containers = [
          {
            name = "main"
            image = "${each.value.image}:${each.value.tag}"
            resources = {
              cpu = each.value.cpu_requests
              memory = each.value.mem_requests
            }
          }         
        ]
        scale = {
          minReplicas = each.value.min_replicas
          maxReplicas = each.value.max_replicas
        }
      }
    }
  })
  tags = local.tags
}

variables.tf

variable "location" {
  type = string
  default = "westus2"
  description = "WestUS2"
}

variable "container_apps" {
  type = list(object({
    name = string
    image = string
    tag = string
    containerPort = number
    ingress_enabled = bool
    min_replicas = number
    max_replicas = number
    cpu_requests = number
    mem_requests = string
  }))

  default = [ {
   image = "nginx"
   name = "kc-container-app"
   tag = "latest"
   containerPort = 80
   ingress_enabled = true
   min_replicas = 1
   max_replicas = 2
   cpu_requests = 0.5
   mem_requests = "1.0Gi"
  },
  {
   image = "nginx"
   name = "kc-container-app-again"
   tag = "latest"
   containerPort = 80
   ingress_enabled = true
   min_replicas = 1
   max_replicas = 2
   cpu_requests = 0.5
   mem_requests = "1.0Gi"
  }] 
}

monitor.tf

resource "azurerm_monitor_action_group" "email_alert" {
  name                = "email-alert"
  resource_group_name = azurerm_resource_group.rg.name
  short_name          = "email-alert"

  email_receiver {
    name          = "send-email-alert"
    email_address = "email@email.com"
    use_common_alert_schema = true
  }

  depends_on = [
    azurerm_resource_group.rg
  ]  
}

resource "azurerm_monitor_metric_alert" "CPU_Usage_alert" {
  name                = "CPU_Usage_alert"
  resource_group_name = azurerm_resource_group.rg.name
  scopes              = [azapi_resource.aca.id]
  description         = "Alert triggers if CPU Usage exceeds 70000 NanoCores (70%)"
  target_resource_type = "Microsoft.App/containerapps"

  criteria {
    metric_namespace = "Microsoft.App/containerapps"
    metric_name      = "UsageNanoCores"
    aggregation      = "Average"
    operator         = "GreaterThan"
    threshold        = 70000
  }

  action {
    action_group_id = azurerm_monitor_action_group.email_alert.id
  }

  depends_on = [
    azapi_resource.aca,
    azurerm_monitor_action_group.email_alert
  ]
}

Error:

│ Error: Missing resource instance key
│
│   on monitor.tf line 20, in resource "azurerm_monitor_metric_alert" "CPU_Usage_alert":
│   20:   scopes              = [azapi_resource.aca.id]
│
│ Because azapi_resource.aca has "for_each" set, its attributes must be accessed on specific instances.
│
│ For example, to correlate with indices of a referring resource, use:
│     azapi_resource.aca[each.key]

Thank you in advance!

2

You wrote:

and therefore you cannot write:

because azapi_resource.aca is now a collection containing multiple resources, not a single resource. You can’t look up attributes such as id on a collection of resources, you’d have to specify which member of the collection (by name) that you are intending to access.

3

Noted @maxb . Does this mean Ill essentially have to create an alert resource for every container (name) that gets built?

4

I’m only familiar with Terraform, not Azure, so I can’t answer that. Maybe so.