feat: Allow overriding "for" field (#8)

Author: mkilchhofer

README.md

@@ -75,6 +75,7 @@ Every alert supports the following overrides:
 | `no_data_state`    | `string`      | Describes what state to enter when the rule's query returns No Data. Options are `OK`, `NoData`, `KeepLast`, and `Alerting`. Defaults to `OK`. |
 | `annotations`      | `map(string)` | Extra annotations to add. It is also possible to override already defined annotations like `runbook_url`. |
 | `labels`           | `map(string)` | Extra labels to add. It is also possible to override already defined labels like `severity`. |
+| `for`              | `string`      | The amount of time for which the rule must be breached for the rule to be considered to be *Firing*. Before this time has elapsed, the rule is only considered to be *Pending*. Defaults to `0`. |
 
 
 ## TF module documentation
@@ -95,7 +96,7 @@ Every alert supports the following overrides:
 | disable\_provenance | Allow modifying the rule group from other sources than Terraform or the Grafana API. | `bool` | `false` | no |
 | folder\_uid | The UID of the Grafana folder that the alerts belongs to. | `string` | n/a | yes |
 | org\_id | The Organization ID of of the Grafana Alerting rule groups. (Only supported with basic auth, API keys are already org-scoped) | `string` | `null` | no |
-| overrides | Overrides per Alert rule | <pre>map(object({<br>    alert_threshold = optional(number)<br>    exec_err_state  = optional(string)<br>    expr            = optional(string)<br>    is_paused       = optional(bool)<br>    no_data_state   = optional(string)<br>    labels          = optional(map(string))<br>    annotations     = optional(map(string))<br>  }))</pre> | `{}` | no |
+| overrides | Overrides per Alert rule | <pre>map(object({<br>    alert_threshold = optional(number)<br>    exec_err_state  = optional(string)<br>    expr            = optional(string)<br>    is_paused       = optional(bool)<br>    no_data_state   = optional(string)<br>    labels          = optional(map(string))<br>    annotations     = optional(map(string))<br>    for             = optional(string)<br>  }))</pre> | `{}` | no |
 | prometheus\_alerts\_file\_path | Path to the Prometheus Alerting rules file | `string` | n/a | yes |
 
 ### Outputs

grafana_alert.tf

@@ -20,7 +20,7 @@ resource "grafana_rule_group" "this" {
 
     content {
       name      = rule.value.alert
-      for       = try(rule.value.for, null)
+      for       = try(var.overrides[rule.value.alert].for, rule.value.for, null)
       condition = "ALERTCONDITION"
 
       annotations = {

test/test.tf

@@ -56,5 +56,9 @@ module "test_vmagent" {
         mycustomlabel = "foobar"
       }
     }
+
+    "TooManyScrapeErrors" = {
+      "for" = "20m"
+    }
   }
 }

variables.tf

@@ -23,6 +23,7 @@ variable "overrides" {
     no_data_state   = optional(string)
     labels          = optional(map(string))
     annotations     = optional(map(string))
+    for             = optional(string)
   }))
   default = {}
 }