Author: thomasm
Date: Tue Dec 3 13:48:36 2013
New Revision: 1547390
URL: http://svn.apache.org/r1547390
Log:
OAK-760 MongoBlobStore: read from a secondary member when possible
Modified:
jackrabbit/oak/trunk/oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/mongomk/blob/MongoBlobStore.java
Modified:
jackrabbit/oak/trunk/oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/mongomk/blob/MongoBlobStore.java
URL:
http://svn.apache.org/viewvc/jackrabbit/oak/trunk/oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/mongomk/blob/MongoBlobStore.java?rev=1547390&r1=1547389&r2=1547390&view=diff
==============================================================================
---
jackrabbit/oak/trunk/oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/mongomk/blob/MongoBlobStore.java
(original)
+++
jackrabbit/oak/trunk/oak-core/src/main/java/org/apache/jackrabbit/oak/plugins/mongomk/blob/MongoBlobStore.java
Tue Dec 3 13:48:36 2013
@@ -29,6 +29,7 @@ import com.mongodb.DBCollection;
import com.mongodb.DBObject;
import com.mongodb.MongoException;
import com.mongodb.QueryBuilder;
+import com.mongodb.ReadPreference;
import com.mongodb.WriteResult;
/**
@@ -160,7 +161,19 @@ public class MongoBlobStore extends Abst
private MongoBlob getBlob(String id, long lastMod) {
DBObject query = getBlobQuery(id, lastMod);
- return (MongoBlob) getBlobCollection().findOne(query);
+
+ // try the secondary first
+ // TODO add a configuration option for whether to try reading from
secondary
+ ReadPreference pref = ReadPreference.secondaryPreferred();
+ DBObject fields = new BasicDBObject();
+ fields.put(MongoBlob.KEY_DATA, 1);
+ MongoBlob blob = (MongoBlob) getBlobCollection().findOne(query,
fields, pref);
+ if (blob == null) {
+ // not found in the secondary: try the primary
+ pref = ReadPreference.primary();
+ blob = (MongoBlob) getBlobCollection().findOne(query, fields,
pref);
+ }
+ return blob;
}
private static DBObject getBlobQuery(String id, long lastMod) {
