[improve] Added event fingerprint stages

l9helper.go

@@ -9,7 +9,8 @@ import (
 )
 
 var fingerPrintLength = 32
-
+var hashLength = 4 // fnv.New32
+var prefixLength = fingerPrintLength-hashLength
 func (event *L9Event) UpdateFingerprint() error {
 	hasher := fnv.New32()
 	summaryScanner := bufio.NewScanner(strings.NewReader(event.Summary))
@@ -39,14 +40,19 @@ func (event *L9Event) UpdateFingerprint() error {
 			return errors.New("event hashing error")
 		}
 		fullHash = append(fullHash, hasher.Sum([]byte{})...)
-		if len(fullHash) >= fingerPrintLength {
+		if len(fullHash) >= prefixLength {
 			break
 		}
 	}
 	// Pad our hash if we're out of data
-	for len(fullHash) < fingerPrintLength {
+	for len(fullHash) < prefixLength {
 		fullHash = append(fullHash, hasher.Sum([]byte{})...)
 	}
+	n, err = hasher.Write([]byte(event.Summary))
+	if err != nil || n != len(event.Summary) {
+		return errors.New("event hashing error")
+	}
+	fullHash = append(fullHash, hasher.Sum([]byte{})...)
 	// Final check
 	if len(fullHash) != fingerPrintLength {
 		return errors.New("event hashing error, blame the author")

l9helper_test.go

@@ -0,0 +1,31 @@
+package l9format
+
+import (
+	"strings"
+	"testing"
+)
+
+var TestEventsByFingerprint = map[string]L9Event{
+	"bc2c0be9cd8fd9c886876c74fe77280819bd01b4a72ac148e2c94bf475b0fd34": {EventSource: "test",Summary: strings.Repeat("test\n",300)},
+	"bc2c0be9cd8fd9c886876c74fe77280819bd01b4a72ac148e2c94bf431f15032": {EventSource: "test",Summary: strings.Repeat("test\n",299)},
+	"5a2c67df7b758a1eb5b5f87eed5cadde5abff03ee094719ed1bbd7fe1282b070": {EventSource: "testing",Summary: strings.Repeat("test\n",299)},
+	"5a2c67df7b758a1eb5b5f87eed5caddeed5caddeed5caddeed5caddefe9efc5e": {EventSource: "testing",Summary: strings.Repeat("test\n",2)},
+	"5a2c67df7b758a1eb5b5f87eed5cadde5abff03e5abff03e5abff03e988de430": {EventSource: "testing",Summary: strings.Repeat("test\n",3)},
+}
+
+func TestL9Event_UpdateFingerprint(t *testing.T) {
+	for fingerprint, event := range TestEventsByFingerprint {
+		err := event.UpdateFingerprint()
+		if err != nil {
+			t.Error(err)
+		}
+		if len(event.EventFingerprint) != fingerPrintLength*2 {
+			t.Errorf("fingerprint length IS not %d: %s", fingerPrintLength*2, event.EventFingerprint)
+		}
+		if fingerprint != event.EventFingerprint {
+			t.Errorf("fingerprint %s doesn't match base %s", event.EventFingerprint, fingerprint)
+		}
+	}
+
+}
+