feat(fastly_alerts): add percentage alerts

docs/resources/alert.md

@@ -70,6 +70,10 @@ Required:
 - `threshold` (Number) Threshold used to alert.
 - `type` (String) Type of strategy to use to evaluate. One of: `above_threshold`, `below_threshold`.
 
+Optional:
+
+- `ignore_below` (Number) Floor noise that can be configured to ignore data points that are below this threshold.
+
 
 <a id="nestedblock--dimensions"></a>
 ### Nested Schema for `dimensions`

fastly/resource_fastly_alert.go

@@ -57,6 +57,11 @@ func resourceFastlyAlert() *schema.Resource {
 				MaxItems:    1,
 				Elem: &schema.Resource{
 					Schema: map[string]*schema.Schema{
+						"ignore_below": {
+							Type:        schema.TypeFloat,
+							Optional:    true,
+							Description: "Floor noise that can be configured to ignore data points that are below this threshold.",
+						},
 						"period": {
 							Type:        schema.TypeString,
 							Required:    true,
@@ -291,11 +296,25 @@ func buildDimensions(data map[string][]string, v map[string]any) map[string][]st
 }
 
 func buildEvaluationStrategy(v map[string]any) map[string]any {
-	return map[string]any{
-		"type":      v["type"].(string),
-		"period":    v["period"].(string),
-		"threshold": v["threshold"].(float64),
+	evaluationStrategy := map[string]any{}
+
+	if value, ok := v["type"]; ok {
+		evaluationStrategy["type"] = value.(string)
+	}
+
+	if value, ok := v["period"]; ok {
+		evaluationStrategy["period"] = value.(string)
 	}
+
+	if value, ok := v["threshold"]; ok {
+		evaluationStrategy["threshold"] = value.(float64)
+	}
+
+	if value, ok := v["ignore_below"]; ok {
+		evaluationStrategy["ignore_below"] = value.(float64)
+	}
+
+	return evaluationStrategy
 }
 
 func buildStringSlice(s *schema.Set) []string {

fastly/resource_fastly_alert_test.go

@@ -193,6 +193,69 @@ func TestAccFastlyAlert_basic_stats_aggregate(t *testing.T) {
 	})
 }
 
+func TestAccFastlyAlert_basic_stats_aggregate_percent(t *testing.T) {
+	service := gofastly.ServiceDetail{
+		Name:      gofastly.ToPointer(""),
+		ServiceID: gofastly.ToPointer(""),
+	}
+
+	createAlert := gofastly.AlertDefinition{
+		Description: "Terraform percent test",
+		Dimensions:  map[string][]string{},
+		// 25 percent increase
+		EvaluationStrategy: map[string]any{
+			"type":         "percent_increase",
+			"period":       "2m",
+			"threshold":    0.25,
+			"ignore_below": float64(10),
+		},
+		Metric: "status_4xx",
+		Name:   fmt.Sprintf("Terraform test percent alert %s", acctest.RandString(10)),
+		Source: "stats",
+	}
+	updateAlert := gofastly.AlertDefinition{
+		Description: "Terraform test with new description",
+		Dimensions:  map[string][]string{},
+		// 10 percent increase
+		EvaluationStrategy: map[string]any{
+			"type":         "percent_increase",
+			"period":       "2m",
+			"threshold":    0.1,
+			"ignore_below": float64(10),
+		},
+		Metric: "status_4xx",
+		Name:   fmt.Sprintf("Terraform test update percent alert %s", acctest.RandString(10)),
+		Source: "stats",
+	}
+
+	resource.ParallelTest(t, resource.TestCase{
+		PreCheck: func() {
+			testAccPreCheck(t)
+		},
+		ProviderFactories: testAccProviders,
+		CheckDestroy:      testAccCheckAlertDestroy,
+		Steps: []resource.TestStep{
+			{
+				Config: testAccAlertPercentAggregateStatsConfig(createAlert),
+				Check: resource.ComposeTestCheckFunc(
+					testAccCheckFastlyAlertsRemoteState(&service, "", createAlert),
+				),
+			},
+			{
+				Config: testAccAlertPercentAggregateStatsConfig(updateAlert),
+				Check: resource.ComposeTestCheckFunc(
+					testAccCheckFastlyAlertsRemoteState(&service, "", updateAlert),
+				),
+			},
+			{
+				ResourceName:      "fastly_alert.tf_percent",
+				ImportState:       true,
+				ImportStateVerify: true,
+			},
+		},
+	})
+}
+
 func testAccCheckFastlyAlertsRemoteState(service *gofastly.ServiceDetail, serviceName string, expected gofastly.AlertDefinition) resource.TestCheckFunc {
 	return func(_ *terraform.State) error {
 		if gofastly.ToValue(service.Name) != serviceName {
@@ -359,3 +422,21 @@ resource "fastly_alert" "tf_bar" {
   }
 }`, alert.Name, alert.Description, alert.Source, alert.Metric, alert.EvaluationStrategy["type"], alert.EvaluationStrategy["period"], alert.EvaluationStrategy["threshold"])
 }
+
+func testAccAlertPercentAggregateStatsConfig(alert gofastly.AlertDefinition) string {
+	return fmt.Sprintf(`
+resource "fastly_alert" "tf_percent" {
+  name = "%s"
+  description = "%s"
+  service_id = ""
+  source = "%s"
+  metric = "%s"
+
+  evaluation_strategy {
+    type = "%s"
+    period = "%s"
+    threshold = %v
+    ignore_below = %v
+  }
+}`, alert.Name, alert.Description, alert.Source, alert.Metric, alert.EvaluationStrategy["type"], alert.EvaluationStrategy["period"], alert.EvaluationStrategy["threshold"], alert.EvaluationStrategy["ignore_below"])
+}