organize error

Author: mmreza79

errors.go

@@ -17,6 +17,12 @@ var (
 	errTopicNotFound = errors.New("requested topic was not found")
 )
 
+type topicNoCreateError string
+
+func (e topicNoCreateError) Error() string {
+	return fmt.Sprintf("topic '%s' does not exist but the manager is configured with NoCreate, so it will not attempt to create it", string(e))
+}
+
 // this regex matches the package name + some hash info, if we're in gomod but not subpackages
 // examples which match
 // * github.com/lovoo/goka/processor.go

topic_manager.go

@@ -172,17 +172,15 @@ func (m *topicManager) ensureExists(topic string, npar, rfactor int, config map[
 
 	partitions, err := m.Partitions(topic)
 
-	if err != nil {
-		if err != errTopicNotFound {
-			return fmt.Errorf("error checking topic: %v", err)
-		}
+	if err != nil && err != errTopicNotFound {
+		return fmt.Errorf("error checking topic: %v", err)
 	}
 	// no topic yet, let's create it
 	if len(partitions) == 0 {
 
 		// (or not)
 		if m.topicManagerConfig.NoCreate {
-			return fmt.Errorf("topic `%s` does not exist but the manager is configured with NoCreate, so it will not attempt to create it", topic)
+			return topicNoCreateError(topic)
 		}
 
 		return m.createTopic(topic,
@@ -195,7 +193,7 @@ func (m *topicManager) ensureExists(topic string, npar, rfactor int, config map[
 
 	// partitions do not match
 	if len(partitions) != npar {
-		return m.handleConfigMismatch(fmt.Sprintf("partition count mismatch for topic %s. Need %d, but existing topic has %d", topic, npar, len(partitions)))
+		return m.handleConfigMismatch(fmt.Sprintf("partition count mismatch for topic '%s'. Need %d, but existing topic has %d", topic, npar, len(partitions)))
 	}
 
 	// check additional config values via the cluster admin if our current version supports it

topic_manager_test.go

@@ -269,7 +269,7 @@ func TestTM_EnsureStreamExists(t *testing.T) {
 		)
 
 		err := tm.EnsureStreamExists(topic, npar)
-		require.Equal(t, err.Error(), "topic `some-topic` does not exist but the manager is configured with NoCreate, so it will not attempt to create it")
+		require.ErrorIs(t, err, topicNoCreateError(topic))
 	})
 	t.Run("fail", func(t *testing.T) {
 		tm, bm, ctrl := createTopicManager(t)