Add boolean thresholds for kapacitor threshold alerts

kapacitor/vars.go

@@ -76,10 +76,12 @@ func Vars(rule chronograf.AlertRule) (string, error) {
 	}
 }
 
+// NotEmpty is an error collector checking if strings are empty values
 type NotEmpty struct {
 	Err error
 }
 
+// Valid checks if string s is empty and if so reports an error using name
 func (n *NotEmpty) Valid(name, s string) error {
 	if n.Err != nil {
 		return n.Err
@@ -91,6 +93,7 @@ func (n *NotEmpty) Valid(name, s string) error {
 	return n.Err
 }
 
+// Escape sanitizes strings with single quotes for kapacitor
 func Escape(str string) string {
 	return strings.Replace(str, "'", `\'`, -1)
 }
@@ -251,5 +254,10 @@ func formatValue(value string) string {
 	if _, err := strconv.ParseFloat(value, 64); err == nil {
 		return value
 	}
-	return "'" + value + "'"
+
+	// If the value is a kapacitor boolean value perform no formatting
+	if value == "TRUE" || value == "FALSE" {
+		return value
+	}
+	return "'" + Escape(value) + "'"
 }

kapacitor/vars_test.go

@@ -49,3 +49,39 @@ func TestVarsCritStringEqual(t *testing.T) {
 		t.Errorf("Error validating alert: %v %s", err, tick)
 	}
 }
+
+func Test_formatValue(t *testing.T) {
+	tests := []struct {
+		name  string
+		value string
+		want  string
+	}{
+		{
+			name:  "parses floats",
+			value: "3.14",
+			want:  "3.14",
+		},
+		{
+			name:  "parses booleans",
+			value: "TRUE",
+			want:  "TRUE",
+		},
+		{
+			name:  "single quotes for strings",
+			value: "up",
+			want:  "'up'",
+		},
+		{
+			name:  "handles escaping of single quotes",
+			value: "down's",
+			want:  "'down\\'s'",
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := formatValue(tt.value); got != tt.want {
+				t.Errorf("formatValue() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}