Merge pull request mongeez#25 from davidmc24/2.4-compatibility

MongeezDao: add support for MongoDB 2.4

src/main/java/org/mongeez/dao/MongeezDao.java

@@ -46,6 +46,7 @@ public MongeezDao(Mongo mongo, String databaseName, MongoAuth auth) {
     private void configure() {
         addTypeToUntypedRecords();
         loadConfigurationRecord();
+        dropObsoleteChangeSetExecutionIndices();
         ensureChangeSetExecutionIndex();
     }
 
@@ -84,9 +85,22 @@ private void loadConfigurationRecord() {
         }
     }
 
+    /**
+     * Removes indices that were generated by versions before 0.9.3, since they're not supported by MongoDB 2.4+
+     */
+    private void dropObsoleteChangeSetExecutionIndices() {
+        String indexName = "type_changeSetExecution_file_1_changeId_1_author_1_resourcePath_1";
+        DBCollection collection = getMongeezCollection();
+        for (DBObject dbObject : collection.getIndexInfo()) {
+            if (indexName.equals(dbObject.get("name"))) {
+                collection.dropIndex(indexName);
+            }
+        }
+    }
+
     private void ensureChangeSetExecutionIndex() {
         BasicDBObject keys = new BasicDBObject();
-        keys.append("type", RecordType.changeSetExecution.name());
+        keys.append("type", 1);
         for (ChangeSetAttribute attribute : changeSetAttributes) {
             keys.append(attribute.name(), 1);
         }