add kapacitor range alerting to API

chronograf.go

@@ -139,11 +139,13 @@ type Ticker interface {
 
 // TriggerValues specifies the alerting logic for a specific trigger type
 type TriggerValues struct {
-	Change   string `json:"change,omitempty"`   // Change specifies if the change is a percent or absolute
-	Period   string `json:"period,omitempty"`   // Period length of time before deadman is alerted
-	Shift    string `json:"shift,omitempty"`    // Shift is the amount of time to look into the past for the alert to compare to the present
-	Operator string `json:"operator,omitempty"` // Operator for alert comparison
-	Value    string `json:"value,omitempty"`    // Value is the boundary value when alert goes critical
+	Change        string `json:"change,omitempty"`         // Change specifies if the change is a percent or absolute
+	Period        string `json:"period,omitempty"`         // Period length of time before deadman is alerted
+	Shift         string `json:"shift,omitempty"`          // Shift is the amount of time to look into the past for the alert to compare to the present
+	Operator      string `json:"operator,omitempty"`       // Operator for alert comparison
+	RangeOperator string `json:"range_operator,omitempty"` // RangeOperator is an optional operator for range comparisons
+	Value         string `json:"value,omitempty"`          // Value is the boundary value when alert goes critical
+	RangeValue    string `json:"range_value,omitempty"`    // RangeValue is an optional value for range comparisons
 }
 
 // Field represent influxql fields and functions from the UI
@@ -247,7 +249,7 @@ type DashboardCell struct {
 
 // DashboardsStore is the storage and retrieval of dashboards
 type DashboardsStore interface {
-  // All lists all dashboards from the DashboardStore
+	// All lists all dashboards from the DashboardStore
 	All(context.Context) ([]Dashboard, error)
 	// Create a new Dashboard in the DashboardStore
 	Add(context.Context, Dashboard) (Dashboard, error)

kapacitor/tickscripts_test.go

@@ -199,6 +199,154 @@ trigger
 	}
 }
 
+func TestThresholdRange(t *testing.T) {
+	alert := chronograf.AlertRule{
+		Name:    "name",
+		Trigger: "threshold",
+		Alerts:  []string{"slack", "victorops", "email"},
+		TriggerValues: chronograf.TriggerValues{
+			Operator:      "greater than",
+			Value:         "90",
+			RangeOperator: "less than",
+			RangeValue:    "100",
+		},
+		Every:   "30s",
+		Message: "message",
+		Query: chronograf.QueryConfig{
+			Database:        "telegraf",
+			Measurement:     "cpu",
+			RetentionPolicy: "autogen",
+			Fields: []chronograf.Field{
+				{
+					Field: "usage_user",
+					Funcs: []string{"mean"},
+				},
+			},
+			Tags: map[string][]string{
+				"host": []string{
+					"acc-0eabc309-eu-west-1-data-3",
+					"prod",
+				},
+				"cpu": []string{
+					"cpu_total",
+				},
+			},
+			GroupBy: chronograf.GroupBy{
+				Time: "10m",
+				Tags: []string{"host", "cluster_id"},
+			},
+			AreTagsAccepted: true,
+			RawText:         "",
+		},
+	}
+
+	tests := []struct {
+		name    string
+		alert   chronograf.AlertRule
+		want    chronograf.TICKScript
+		wantErr bool
+	}{
+		{
+			name:  "Test valid template alert",
+			alert: alert,
+			want: `var db = 'telegraf'
+
+var rp = 'autogen'
+
+var measurement = 'cpu'
+
+var groupBy = ['host', 'cluster_id']
+
+var whereFilter = lambda: ("cpu" == 'cpu_total') AND ("host" == 'acc-0eabc309-eu-west-1-data-3' OR "host" == 'prod')
+
+var period = 10m
+
+var every = 30s
+
+var name = 'name'
+
+var idVar = name + ':{{.Group}}'
+
+var message = 'message'
+
+var idTag = 'alertID'
+
+var levelTag = 'level'
+
+var messageField = 'message'
+
+var durationField = 'duration'
+
+var outputDB = 'chronograf'
+
+var outputRP = 'autogen'
+
+var outputMeasurement = 'alerts'
+
+var triggerType = 'threshold'
+
+var lower = 90
+
+var upper = 100
+
+var data = stream
+    |from()
+        .database(db)
+        .retentionPolicy(rp)
+        .measurement(measurement)
+        .groupBy(groupBy)
+        .where(whereFilter)
+    |window()
+        .period(period)
+        .every(every)
+        .align()
+    |mean('usage_user')
+        .as('value')
+
+var trigger = data
+    |alert()
+        .crit(lambda: "value" > lower AND "value" < upper)
+        .stateChangesOnly()
+        .message(message)
+        .id(idVar)
+        .idTag(idTag)
+        .levelTag(levelTag)
+        .messageField(messageField)
+        .durationField(durationField)
+        .slack()
+        .victorOps()
+        .email()
+
+trigger
+    |influxDBOut()
+        .create()
+        .database(outputDB)
+        .retentionPolicy(outputRP)
+        .measurement(outputMeasurement)
+        .tag('alertName', name)
+        .tag('triggerType', triggerType)
+
+trigger
+    |httpOut('output')
+`,
+			wantErr: false,
+		},
+	}
+	for _, tt := range tests {
+		gen := Alert{}
+		got, err := gen.Generate(tt.alert)
+		if (err != nil) != tt.wantErr {
+			t.Errorf("%q. Threshold() error = %v, wantErr %v", tt.name, err, tt.wantErr)
+			continue
+		}
+		if got != tt.want {
+			diff := diffmatchpatch.New()
+			delta := diff.DiffMain(string(tt.want), string(got), true)
+			t.Errorf("%q\n%s", tt.name, diff.DiffPrettyText(delta))
+		}
+	}
+}
+
 func TestThresholdNoAggregate(t *testing.T) {
 	alert := chronograf.AlertRule{
 		Name:    "name",

kapacitor/triggers.go

@@ -34,6 +34,12 @@ var ThresholdTrigger = `
     .crit(lambda: "value" %s crit)
 `
 
+var ThresholdRangeTrigger = `
+	var trigger = data
+	|alert()
+		.crit(lambda: "value" %s lower AND "value" %s upper)
+`
+
 // RelativeAbsoluteTrigger compares one window of data versus another (current - past)
 var RelativeAbsoluteTrigger = `
 var past = data
@@ -83,7 +89,11 @@ func Trigger(rule chronograf.AlertRule) (string, error) {
 	case Relative:
 		trigger, err = relativeTrigger(rule)
 	case Threshold:
-		trigger, err = thresholdTrigger(rule)
+		if rule.TriggerValues.RangeOperator == "" || rule.TriggerValues.RangeValue == "" {
+			trigger, err = thresholdTrigger(rule)
+		} else {
+			trigger, err = thresholdRangeTrigger(rule)
+		}
 	default:
 		trigger, err = "", fmt.Errorf("Unknown trigger type: %s", rule.Trigger)
 	}
@@ -116,3 +126,15 @@ func thresholdTrigger(rule chronograf.AlertRule) (string, error) {
 	}
 	return fmt.Sprintf(ThresholdTrigger, op), nil
 }
+
+func thresholdRangeTrigger(rule chronograf.AlertRule) (string, error) {
+	op, err := kapaOperator(rule.TriggerValues.Operator)
+	if err != nil {
+		return "", err
+	}
+	rangeOp, err := kapaOperator(rule.TriggerValues.RangeOperator)
+	if err != nil {
+		return "", err
+	}
+	return fmt.Sprintf(ThresholdRangeTrigger, op, rangeOp), nil
+}

kapacitor/vars.go

@@ -34,13 +34,25 @@ func Vars(rule chronograf.AlertRule) (string, error) {
 
 	switch rule.Trigger {
 	case Threshold:
-		vars := `
+		if rule.TriggerValues.RangeOperator == "" || rule.TriggerValues.RangeValue == "" {
+			vars := `
 		%s
         var crit = %s
  `
-		return fmt.Sprintf(vars,
-			common,
-			rule.TriggerValues.Value), nil
+			return fmt.Sprintf(vars,
+				common,
+				rule.TriggerValues.Value), nil
+		} else {
+			vars := `
+			%s
+					var lower = %s
+					var upper = %s
+	 `
+			return fmt.Sprintf(vars,
+				common,
+				rule.TriggerValues.Value,
+				rule.TriggerValues.RangeValue), nil
+		}
 	case Relative:
 		vars := `
 		%s