Ilm disable template (jaegertracing#3610)

* useILM will prevent index template creation

The index template should be created by es-rollover. Without this, it
was mandatory to use --es.create-index-templates=false with
--es.use-ilm, otherwise it would override the index template with an
empty lifecycle.name thus preventing the rollover to work

Signed-off-by: Raphael Bizos <r.bizos@criteo.com>

* fixing ILM test

Signed-off-by: Raphael Bizos <r.bizos@criteo.com>

* Adding a comment for ILM and index creation

Signed-off-by: Raphael Bizos <r.bizos@criteo.com>
Signed-off-by: Albert Teoh <see.kwang.teoh@gmail.com>

plugin/storage/es/factory.go

@@ -199,7 +199,9 @@ func createSpanWriter(
 		Archive:                archive,
 		UseReadWriteAliases:    cfg.GetUseReadWriteAliases(),
 	})
-	if cfg.IsCreateIndexTemplates() {
+
+	// Creating a template here would conflict with the one created for ILM resulting to no index rollover
+	if cfg.IsCreateIndexTemplates() && !cfg.GetUseILM() {
 		err := writer.CreateTemplates(spanMapping, serviceMapping, cfg.GetIndexPrefix())
 		if err != nil {
 			return nil, err

plugin/storage/es/factory_test.go

@@ -185,6 +185,16 @@ func TestCreateTemplateError(t *testing.T) {
 	assert.Error(t, err, "template-error")
 }
 
+func TestILMDisableTemplateCreation(t *testing.T) {
+	f := NewFactory()
+	f.primaryConfig = &mockClientBuilder{createTemplateError: errors.New("template-error"), Configuration: escfg.Configuration{Enabled: true, UseILM: true, UseReadWriteAliases: true, CreateIndexTemplates: true}}
+	f.archiveConfig = &mockClientBuilder{}
+	err := f.Initialize(metrics.NullFactory, zap.NewNop())
+	require.NoError(t, err)
+	_, err = f.CreateSpanWriter()
+	assert.Nil(t, err) // as the createTemplate is not called, CreateSpanWriter should not return an error
+}
+
 func TestArchiveDisabled(t *testing.T) {
 	f := NewFactory()
 	f.archiveConfig = &mockClientBuilder{Configuration: escfg.Configuration{Enabled: false}}