Ensure callback is called

main.go

@@ -18,7 +18,7 @@ import (
 	"time"
 )
 
-type callbackFunc func(rules yara.MatchRules)
+type callbackFunc func(*yara.MatchRules, error)
 
 type Job struct {
 	Data     io.ReadCloser
@@ -106,11 +106,16 @@ func scanHandler(w http.ResponseWriter, r *http.Request) {
 
 		wg := &sync.WaitGroup{}
 
-		results := make([]yara.MatchRules, 0)
+		results := make([]*yara.MatchRules, 0)
 
-		jobCallback := func(m yara.MatchRules) {
-			results = append(results, m)
+		jobCallback := func(m *yara.MatchRules, err error) {
 			wg.Done()
+
+			if err != nil {
+				return
+			}
+
+			results = append(results, m)
 		}
 
 		log.WithField("contentType", contentType).Debug("Adding files from multipart form as jobs")
@@ -143,12 +148,20 @@ func scanHandler(w http.ResponseWriter, r *http.Request) {
 
 		wg.Wait()
 
+		log.WithField("matches", w).Debug("Matched rules")
 		json.NewEncoder(w).Encode(results)
 	default:
 		job := &Job{
 			Data: r.Body,
-			Callback: func(m yara.MatchRules) {
-				json.NewEncoder(w).Encode(m)
+			Callback: func(m *yara.MatchRules, err error) {
+				log.WithField("match", m).Debug("Matched rules")
+
+				if err != nil {
+					w.WriteHeader(http.StatusInternalServerError)
+					w.Write([]byte(err.Error()))
+				} else {
+					json.NewEncoder(w).Encode(m)
+				}
 			},
 		}
 
@@ -235,19 +248,16 @@ func processJob(s *yara.Scanner, job *Job) {
 	b, err := io.ReadAll(job.Data)
 
 	if err != nil {
+		job.Callback(nil, err)
 		return
 	}
 
 	err = s.SetCallback(&m).ScanMem(b)
 
 	if err != nil {
+		job.Callback(nil, err)
 		return
 	}
 
-	// Respond with job
-	if len(m) < 1 {
-		return
-	}
-
-	job.Callback(m)
+	job.Callback(&m, nil)
 }