Code review fixes

@@ -323,8 +323,11 @@ audit_log:
     # Name of the index where audit logs stored
     # Index name could contain next placeholders (not mandatory):
     # @{TENANT} - substituted by tenant ID
-    # @{DATE} - substituted by current date in YYYY.MM.DD format
+    # @{DATE} - substituted by current date in format provided in audit_log.sink.date_format
     index_pattern: "${AUDIT_LOG_SINK_INDEX_PATTERN:@{TENANT}_AUDIT_LOG_@{DATE}}"
+    # Date format. Details of the pattern could be found here:
+    # https://docs.oracle.com/javase/8/docs/api/java/time/format/DateTimeFormatter.html
+    date_format: "${AUDIT_LOG_SINK_DATE_FORMAT:YYYY.MM.DD}"
     scheme_name: "${AUDIT_LOG_SINK_SCHEME_NAME:http}" # http or https
     host: "${AUDIT_LOG_SINK_HOST:localhost}"
     port: "${AUDIT_LOG_SINK_POST:9200}"

@@ -300,7 +300,6 @@ public class AuditLogServiceImpl implements AuditLogService {
         futures.add(auditLogDao.saveByTenantIdAndCustomerId(auditLogEntry));
         futures.add(auditLogDao.saveByTenantIdAndUserId(auditLogEntry));
 
-        // TODO: is this correct place to log action into sink?
         auditLogSink.logAction(auditLogEntry);
 
         return Futures.allAsList(futures);

@@ -50,8 +50,6 @@ public class ElasticsearchAuditLogSink implements AuditLogSink {
 
     private static final String TENANT_PLACEHOLDER = "@{TENANT}";
     private static final String DATE_PLACEHOLDER = "@{DATE}";
-    private static final String DATE_FORMAT = "YYYY.MM.dd";
-
     private static final String INDEX_TYPE = "audit_log";
 
     private final ObjectMapper mapper = new ObjectMapper();
@@ -68,6 +66,8 @@ public class ElasticsearchAuditLogSink implements AuditLogSink {
     private String userName;
     @Value("${audit_log.sink.password}")
     private String password;
+    @Value("${audit_log.sink.date_format}")
+    private String dateFormat;
 
     private RestClient restClient;
 
@@ -152,7 +152,7 @@ public class ElasticsearchAuditLogSink implements AuditLogSink {
         }
         if (indexName.contains(DATE_PLACEHOLDER)) {
             LocalDateTime now = LocalDateTime.now();
-            DateTimeFormatter formatter = DateTimeFormatter.ofPattern(DATE_FORMAT);
+            DateTimeFormatter formatter = DateTimeFormatter.ofPattern(dateFormat);
             indexName = indexName.replace(DATE_PLACEHOLDER, now.format(formatter));
         }
         return indexName.toLowerCase();