feat(alerting): starting work on condition evaluation

pkg/services/alerting/conditions_test.go

+package alerting
+
+import (
+	"testing"
+
+	"github.com/grafana/grafana/pkg/components/simplejson"
+	. "github.com/smartystreets/goconvey/convey"
+)
+
+func TestQueryCondition(t *testing.T) {
+
+	Convey("when evaluating query condition", t, func() {
+
+		Convey("Given avg() and > 100", func() {
+
+			jsonModel, err := simplejson.NewJson([]byte(`{
+            "type": "query",
+            "query":  {
+              "params": ["A", "5m", "now"],
+              "datasourceId": 1,
+              "model": {"target": "aliasByNode(statsd.fakesite.counters.session_start.mobile.count, 4)"}
+            },
+            "reducer": {"type": "avg", "params": []},
+            "evaluator": {"type": ">", "params": [100]}
+          }`))
+			So(err, ShouldBeNil)
+
+			condition, err := NewQueryCondition(jsonModel)
+			So(err, ShouldBeNil)
+
+			Convey("Should set result to triggered when avg is above 100", func() {
+				context := &AlertResultContext{}
+				condition.Eval(context)
+
+				So(context.Triggered, ShouldBeTrue)
+			})
+		})
+
+	})
+}

pkg/services/alerting/engine.go

@@ -14,7 +14,7 @@ type Engine struct {
 	clock           clock.Clock
 	ticker          *Ticker
 	scheduler       Scheduler
-	handler         AlertingHandler
+	handler         AlertHandler
 	ruleReader      RuleReader
 	log             log.Logger
 	responseHandler ResultHandler

pkg/services/alerting/extractor.go

@@ -90,6 +90,7 @@ func (e *DashAlertExtractor) GetAlerts() ([]*m.Alert, error) {
 				Handler:     jsonAlert.Get("handler").MustInt64(),
 				Enabled:     jsonAlert.Get("enabled").MustBool(),
 				Description: jsonAlert.Get("description").MustString(),
+				Severity:    jsonAlert.Get("severity").MustString(),
 				Frequency:   getTimeDurationStringToSeconds(jsonAlert.Get("frequency").MustString()),
 			}
 

pkg/services/alerting/handler.go

@@ -31,6 +31,16 @@ func (e *HandlerImpl) eval(rule *AlertRule) *AlertResultContext {
 
 	for _, condition := range rule.Conditions {
 		condition.Eval(result)
+
+		// break if condition could not be evaluated
+		if result.Error != nil {
+			break
+		}
+
+		// break if result has not triggered yet
+		if result.Triggered == false {
+			break
+		}
 	}
 
 	result.EndTime = time.Now()

pkg/services/alerting/interfaces.go

@@ -2,7 +2,7 @@ package alerting
 
 import "time"
 
-type AlertingHandler interface {
+type AlertHandler interface {
 	Execute(rule *AlertRule, resultChan chan *AlertResultContext)
 }