transact empty result for no-data

policy/goals/differ.go

@@ -11,12 +11,17 @@ import (
 // It returns the storage id for the current query results.
 func GoalResultsDiffer(log skill.Logger, queryResults []GoalEvaluationQueryResult, digest string, goal Goal, previousStorageId string) (bool, string, error) {
 	log.Infof("Generating storage id for goal %s, image %s", goal.Definition, digest)
-	hash, err := hashstructure.Hash(queryResults, hashstructure.FormatV2, nil)
-	if err != nil {
-		return false, "", fmt.Errorf("failed to generate storage id for goal %s, image %s: %s", goal.Definition, digest, err)
-	}
 
-	storageId := fmt.Sprint(hash)
+	storageId := "no-data"
+
+	if queryResults != nil {
+		hash, err := hashstructure.Hash(queryResults, hashstructure.FormatV2, nil)
+		if err != nil {
+			return false, "", fmt.Errorf("failed to generate storage id for goal %s, image %s: %s", goal.Definition, digest, err)
+		}
+
+		storageId = fmt.Sprint(hash)
+	}
 
 	differ := storageId != previousStorageId
 

policy/goals/entities.go

@@ -19,18 +19,25 @@ package goals
 import "time"
 
 func CreateEntitiesFromResults(results []GoalEvaluationQueryResult, goalDefinition string, goalConfiguration string, image string, storageId string, configHash string, evaluationTs time.Time, tx int64) GoalEvaluationResultEntity {
-	return GoalEvaluationResultEntity{
-		Definition:     goalDefinition,
-		Configuration:  goalConfiguration,
-		Subject:        DockerImageEntity{Digest: image},
-		DeviationCount: len(results),
-		StorageId:      storageId,
-		ConfigHash:     configHash,
-		CreatedAt:      evaluationTs,
+	entity := GoalEvaluationResultEntity{
+		Definition:    goalDefinition,
+		Configuration: goalConfiguration,
+		Subject:       DockerImageEntity{Digest: image},
+		ConfigHash:    configHash,
+		CreatedAt:     evaluationTs,
 		TransactionCondition: TransactionConditionEntity{
 			Args: map[string]interface{}{"tx-arg": tx},
 			Where: []byte(`[[?entity :goal.result/created-at _ ?tx true]
 			[(< ?tx ?tx-arg)]]`),
 		},
 	}
+
+	if storageId != "no-data" {
+		deviationCount := len(results)
+
+		entity.DeviationCount = &deviationCount
+		entity.StorageId = &storageId
+	}
+
+	return entity
 }

policy/goals/entities_test.go

@@ -34,11 +34,27 @@ func TestCreateEntitiesFromResult(t *testing.T) {
 
 	entity := CreateEntitiesFromResults(resultModel, "test-definition", "test-configuration", "test-image", "storage-id", "config-hash", evaluationTs, 123)
 
-	if entity.Definition != "test-definition" || entity.Configuration != "test-configuration" || entity.StorageId != "storage-id" || entity.CreatedAt.Format("2006-01-02T15:04:05.000Z") != "2023-07-10T20:01:41.000Z" {
+	if entity.Definition != "test-definition" || entity.Configuration != "test-configuration" || *entity.StorageId != "storage-id" || entity.CreatedAt.Format("2006-01-02T15:04:05.000Z") != "2023-07-10T20:01:41.000Z" {
 		t.Errorf("metadata not set correctly")
 	}
 
-	if entity.DeviationCount != 1 {
+	if *entity.DeviationCount != 1 {
 		t.Errorf("incorrect number of deviations, expected %d, got %d", 1, entity.DeviationCount)
 	}
 }
+
+func TestNoDataDoesntSetFields(t *testing.T) {
+	result := `[{:name "CVE-2023-2650", :details {:purl "pkg:alpine/[email protected]?os_name=alpine&os_version=3.18", :cve "CVE-2023-2650", :severity "HIGH", :fixed-by "3.1.1-r0"} }]`
+
+	resultModel := []GoalEvaluationQueryResult{}
+
+	edn.Unmarshal([]byte(result), &resultModel)
+
+	evaluationTs := time.Date(2023, 7, 10, 20, 1, 41, 0, time.UTC)
+
+	entity := CreateEntitiesFromResults(resultModel, "test-definition", "test-configuration", "test-image", "no-data", "config-hash", evaluationTs, 123)
+
+	if entity.StorageId != nil || entity.DeviationCount != nil {
+		t.Errorf("metadata not set correctly")
+	}
+}

policy/goals/types.go

@@ -45,8 +45,8 @@ type (
 		Definition           string                     `edn:"goal.definition/name"`
 		Configuration        string                     `edn:"goal.configuration/name"`
 		Subject              DockerImageEntity          `edn:"goal.result/subject"`
-		DeviationCount       int                        `edn:"goal.result/deviation-count"`
-		StorageId            string                     `edn:"goal.result/storage-id"`
+		DeviationCount       *int                       `edn:"goal.result/deviation-count"`
+		StorageId            *string                    `edn:"goal.result/storage-id"`
 		ConfigHash           string                     `edn:"goal.result/config-hash"`
 		CreatedAt            time.Time                  `edn:"goal.result/created-at"`
 		TransactionCondition TransactionConditionEntity `edn:"atomist/tx-iff"`

policy/policy_handler/handler.go

@@ -194,8 +194,7 @@ func transact(
 	configHash := storageTuple[1]
 
 	if goalResults == nil {
-		req.Log.Infof("goal %s returned no data for digest %s, skipping storing results", goal.Definition, digest)
-		return skill.NewCompletedStatus(fmt.Sprintf("Goal %s evaluated - no data found", goalName))
+		req.Log.Infof("goal %s returned no data for digest %s", goal.Definition, digest)
 	}
 
 	es, err := storage.NewEvaluationStorage(ctx)
@@ -217,7 +216,7 @@ func transact(
 		differ = true
 	}
 
-	if differ {
+	if differ && goalResults != nil {
 		if err := es.Store(ctx, goalResults, storageId, req.Event.Environment, req.Log); err != nil {
 			return skill.NewFailedStatus(fmt.Sprintf("Failed to store evaluation results for digest %s: %s", digest, err.Error()))
 		}