[Bug]: Can't directly change alerts notification type, need to delete it first

[YusDyr]

Is there an existing issue for this?

• I have searched the existing issues

Provider Version

1.14.0

Terraform Version

1.9.0

Terraform Edition

Terraform Open Source (OSS)

Current Behavior

When I created alerts with one notification type, such as, for example, PAGER_DUTY or SLACK and now want to change it to another notification type, such as TEAMS, I constantly got errors related to notification-specific parameters. It seems like the terraform checks first compatibility between existing notification parameters and new notification type even despite these conflicting parameters should be deleted on update.

Terraform configuration to reproduce the issue

variable "environment" {
  description = "Name of the environment where table is being deployed."
  type        = string
}

variable "alerts_no_primary" {
  description = "[no_primary] Alert settings"
  type = object({
    create        = optional(bool, true)
    enable        = optional(bool, true)
    interval_min  = optional(number, 30)
    delay_min     = optional(number, 0)
    notifications = optional(set(string), ["PD", "Teams"])
  })
  default = {}
}

variable "alerts_notifications_config" {
  description = "Alerts notification configs, currently for PD and SLACK"
  type = map(object({
    notification_type = string
    delay_min         = optional(number) # Number of minutes to wait after an alert condition is detected before sending out the first notification.
    interval_min      = optional(number) # Number of minutes to wait between successive notifications for unacknowledged alerts that are not resolved. The minimum value is 5. **NOTE** `PAGER_DUTY`, `VICTOR_OPS`, and `OPS_GENIE` notifications do not return this value. The notification interval must be configured and managed within each external service.
    team_name         = optional(string) # Label for the team that receives this notification
    channel_name      = optional(string) # Attributes for SLACK
    teams_webhook_url = optional(string) # Webhook URL for Teams in case of multiple Teams channel are used
  }))
  default = {
    "PD" = {
      notification_type = "PAGER_DUTY"
    }
    "Teams" = {
      notification_type = "MICROSOFT_TEAMS"
    }
  }
  validation {
    condition     = alltrue([for o in var.alerts_notifications_config : contains(["SLACK", "PAGER_DUTY", "MICROSOFT_TEAMS", "DATADOG"], o.notification_type)])
    error_message = "Currently only these notification_type supported: `SLACK`, `PAGER_DUTY`, `MICROSOFT_TEAMS`, `DATADOG`"
  }
  validation {
    condition     = alltrue([for o in var.alerts_notifications_config : (o.notification_type == "SLACK" ? (var.alerts_slack_token != null ? true : false) : true)])
    error_message = "For SLACK notifications `var.alerts_slack_token` shouldn't be null."
  }
  validation {
    condition     = alltrue([for o in var.alerts_notifications_config : (o.notification_type == "SLACK" ? (o.channel_name != null ? true : false) : true)])
    error_message = "For SLACK notifications `channel_name` parameter shouldn't be null."
  }
  validation {
    condition     = alltrue([for o in var.alerts_notifications_config : (o.notification_type == "PAGER_DUTY" ? (var.pager_duty_service_key != null ? true : false) : true)])
    error_message = "For Pagerduty notifications `var.pager_duty_service_key` shouldn't be null."
  }
  validation {
    condition     = alltrue([for o in var.alerts_notifications_config : (o.notification_type == "MICROSOFT_TEAMS" ? ((var.teams_webhook_url != null || o.teams_webhook_url != null) ? true : false) : true)])
    error_message = "For MS Teams notifications `var.teams_webhook_url` or subkey `teams_webhook_url` shouldn't be null."
  }
  validation {
    condition     = alltrue([for o in var.alerts_notifications_config : (o.notification_type == "DATADOG" ? (var.datadog_api_key != null ? true : false) : true)])
    error_message = "For Datadog notifications `var.datadog_api_key` shouldn't be null."
  }
}

variable "general_alerts_notifications" {
  type    = set(string)
  default = []
}

locals {

  notifications_config = {
    for k, n in var.alerts_notifications_config :
    lower(k) => (
      n.notification_type == "SLACK" ? merge(n, { api_token = var.alerts_slack_token }) :
      n.notification_type == "PAGER_DUTY" ? merge(n, { service_key = var.pager_duty_service_key, interval_min = try(n.interval_min, null) }) :
      n.notification_type == "MICROSOFT_TEAMS" ? merge(n, { microsoft_teams_webhook_url = coalesce(n.teams_webhook_url, var.teams_webhook_url) }) :
      n.notification_type == "DATADOG" ? merge(n, { datadog_api_key = var.datadog_api_key }) :
      n
    )
  }

  is_environment_prod = (
    strcontains(lower(var.environment), "prod") ||
    strcontains(lower(var.environment), "prd")
  )

  # Effective general alerts notifications:
  # - if var.general_alerts_notifications is non-empty -> use it
  # - else:
  #     - prod/prd -> ["PD", "Teams"]
  #     - others  -> ["Teams"]
  # - only keep channels defined in notifications_config
  general_alerts_notifications = distinct([
    for k in(
      length(var.general_alerts_notifications) > 0
      ? var.general_alerts_notifications
      : (
        local.is_environment_prod
        ? ["PD", "Teams"]
        : ["Teams"]
      )
    ) : lower(k)
    if contains(keys(local.notifications_config), lower(k))
  ])
}


resource "mongodbatlas_alert_configuration" "no_primary" {
  count      = var.alerts_no_primary.create ? 1 : 0
  project_id = var.project_id
  event_type = "NO_PRIMARY"
  enabled    = var.alerts_no_primary.enable

  dynamic "notification" {
    for_each = toset(
      coalescelist(
        [for k in tolist(var.alerts_no_primary.notifications) : lower(k)],
        local.general_alerts_notifications
      )
    )
    content {
      type_name                   = local.notifications_config[notification.key].notification_type
      api_token                   = lookup(local.notifications_config[notification.key], "api_token", null)
      channel_name                = lookup(local.notifications_config[notification.key], "channel_name", null)
      service_key                 = lookup(local.notifications_config[notification.key], "service_key", null)
      microsoft_teams_webhook_url = lookup(local.notifications_config[notification.key], "microsoft_teams_webhook_url", null)
      datadog_api_key             = lookup(local.notifications_config[notification.key], "datadog_api_key", null)
      interval_min                = local.notifications_config[notification.key].notification_type != "PAGER_DUTY" ? try(coalesce(var.alerts_no_primary.interval_min, local.notifications_config[notification.key].interval_min), null) : null
      delay_min                   = try(coalesce(var.alerts_no_primary.delay_min, local.notifications_config[notification.key].delay_min), null)
    }
  }

  matcher {
    field_name = "CLUSTER_NAME"
    operator   = "EQUALS"
    value      = var.cluster_name
  }
}

Steps To Reproduce

1. Create first alerts with that config and var.environment = "dev"
2. Change var.environment to "prod"
3. Successfully run terraform plan
4. Fail on terraform apply

Logs

Terraform will perform the following actions:
  # mongodbatlas_alert_configuration.host_is_down[0] will be updated in-place
  ~ resource "mongodbatlas_alert_configuration" "host_is_down" {
        id                     = "aWQ=:NjkxMjViNGIzOGRmNDAyZTYwNWYzZTIw-cHJvamVjdF9pZA==:NjRhYzU1MDRkNTFhYTczMTc0MTEzZmU0"
      ~ updated                = "2025-11-10T21:38:19Z" -> (known after apply)
        # (5 unchanged attributes hidden)
      ~ notification {
          - microsoft_teams_webhook_url = (sensitive value) -> null
          ~ notifier_id                 = "69125b4b38df402e605f3e16" -> (known after apply)
          + service_key                 = (sensitive value)
          + team_name                   = (known after apply)
          ~ type_name                   = "MICROSOFT_TEAMS" -> "PAGER_DUTY"
            # (4 unchanged attributes hidden)
        }
      + notification {
          + delay_min                   = 0
          + email_enabled               = (known after apply)
          + interval_min                = 30
          + microsoft_teams_webhook_url = (sensitive value)
          + notifier_id                 = (known after apply)
          + sms_enabled                 = (known after apply)
          + team_name                   = (known after apply)
          + type_name                   = "MICROSOFT_TEAMS"
        }
        # (1 unchanged block hidden)
    }
  # mongodbatlas_alert_configuration.no_primary[0] will be updated in-place
  ~ resource "mongodbatlas_alert_configuration" "no_primary" {
        id                     = "aWQ=:NjkxMjViNGJiNDkwYjQxOWI3MzBjYWNj-cHJvamVjdF9pZA==:NjRhYzU1MDRkNTFhYTczMTc0MTEzZmU0"
      ~ updated                = "2025-11-10T21:38:19Z" -> (known after apply)
        # (5 unchanged attributes hidden)
      ~ notification {
          - microsoft_teams_webhook_url = (sensitive value) -> null
          ~ notifier_id                 = "69125b4bb490b419b730cac4" -> (known after apply)
          + service_key                 = (sensitive value)
          + team_name                   = (known after apply)
          ~ type_name                   = "MICROSOFT_TEAMS" -> "PAGER_DUTY"
            # (4 unchanged attributes hidden)
        }
      + notification {
          + delay_min                   = 0
          + email_enabled               = (known after apply)
          + interval_min                = 30
          + microsoft_teams_webhook_url = (sensitive value)
          + notifier_id                 = (known after apply)
          + sms_enabled                 = (known after apply)
          + team_name                   = (known after apply)
          + type_name                   = "MICROSOFT_TEAMS"
        }
        # (1 unchanged block hidden)
    }
Plan: 0 to add, 2 to change, 0 to destroy.
mongodbatlas_alert_configuration.no_primary[0]: Modifying... [id=aWQ=:NjkxMjViNGJiNDkwYjQxOWI3MzBjYWNj-cHJvamVjdF9pZA==:NjRhYzU1MDRkNTFhYTczMTc0MTEzZmU0]
mongodbatlas_alert_configuration.host_is_down[0]: Modifying... [id=aWQ=:NjkxMjViNGIzOGRmNDAyZTYwNWYzZTIw-cHJvamVjdF9pZA==:NjRhYzU1MDRkNTFhYTczMTc0MTEzZmU0]
Error: error updating Alert Configuration information: %s
  with mongodbatlas_alert_configuration.host_is_down[0],
  on alerts.tf line 42, in resource "mongodbatlas_alert_configuration" "host_is_down":
  42: resource "mongodbatlas_alert_configuration" "host_is_down" {
'interval_min' must not be set if type_name is 'PAGER_DUTY', 'OPS_GENIE' or
'VICTOR_OPS'
Error: error updating Alert Configuration information: %s
  with mongodbatlas_alert_configuration.no_primary[0],
  on alerts.tf line 76, in resource "mongodbatlas_alert_configuration" "no_primary":
  76: resource "mongodbatlas_alert_configuration" "no_primary" {
'interval_min' must not be set if type_name is 'PAGER_DUTY', 'OPS_GENIE' or
'VICTOR_OPS'
[23:25:22] [ERROR] Failed running apply script

Code of Conduct

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[github-actions]

Thanks for opening this issue! Please make sure you've followed our guidelines when opening the issue. In short, to help us reproduce the issue we need:

• Terraform configuration file used to reproduce the issue
• Terraform log files from the run where the issue occurred
• Terraform Atlas provider version used to reproduce the issue
• Terraform version used to reproduce the issue
• Confirmation if Terraform OSS, Terraform Cloud, or Terraform Enterprise deployment

The ticket CLOUDP-358194 was created for internal tracking.

[EspenAlbert]

Hi @YusDyr Thank you for opening the issue.

I'll have a closer look, but my immediate feeling is that you are not changing the notification only; it looks like one is being changed and another is being added. Is that expected?

If this is intentional I think a workaround to the problem is solved by adding the new notification after the old one:

(
        local.is_environment_prod
        ? ["PD", "Teams"] # CHANGE THIS TO `["Teams", "PD"]
        : ["Teams"]
      )

Maybe some fields need to be explicitly set to empty or null in your Terraform code?
Looks like interval_minmight be left in the state for the changed notification, so it is accidentally sent in the update.

[EspenAlbert]

Hi Again @YusDyr were you able to use the workaround?
I have created a PR #3882 but it might take a few weeks before it is released.

[YusDyr]

Thanks, Espen, it will take some time to check your approach and how I add/change notifications.
Generally speaking I don't add notification but change it - in my cases from Slack to Teams.

[EspenAlbert]

🤔 but isn't that different from what you reported in the issue?
The issue uses Microsoft Teams and Pager Duty