Fix bug where nextContent() always returned all data

2 files changed, 37 insertions, 2 deletions

diff --git a/filedistribution/src/main/java/com/yahoo/vespa/filedistribution/FileReferenceDataBlob.java b/filedistribution/src/main/java/com/yahoo/vespa/filedistribution/FileReferenceDataBlob.java
index f0db12a45fc..c22770395d3 100644
--- a/filedistribution/src/main/java/com/yahoo/vespa/filedistribution/FileReferenceDataBlob.java
+++ b/filedistribution/src/main/java/com/yahoo/vespa/filedistribution/FileReferenceDataBlob.java
@@ -9,6 +9,7 @@ import java.nio.ByteBuffer;
 public class FileReferenceDataBlob extends FileReferenceData {
     private final byte[] content;
     private final long xxhash;
+    private boolean contentRead = false;
 
     public FileReferenceDataBlob(FileReference fileReference, String filename, Type type, byte[] content) {
         this(fileReference, filename, type, content, XXHashFactory.fastestInstance().hash64().hash(ByteBuffer.wrap(content), 0));
@@ -27,10 +28,16 @@ public class FileReferenceDataBlob extends FileReferenceData {
     public ByteBuffer content() {
         return ByteBuffer.wrap(content);
     }
+
     @Override
     public int nextContent(ByteBuffer bb) {
-        bb.put(content);
-        return content.length;
+        if (contentRead) {
+            return -1;
+        } else {
+            contentRead = true;
+            bb.put(content);
+            return content.length;
+        }
     }
 
     @Override
diff --git a/filedistribution/src/test/java/com/yahoo/vespa/filedistribution/FileReferenceDataTest.java b/filedistribution/src/test/java/com/yahoo/vespa/filedistribution/FileReferenceDataTest.java
new file mode 100644
index 00000000000..0b85def5809
--- /dev/null
+++ b/filedistribution/src/test/java/com/yahoo/vespa/filedistribution/FileReferenceDataTest.java
@@ -0,0 +1,28 @@
+// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.filedistribution;
+
+import com.yahoo.config.FileReference;
+import com.yahoo.text.Utf8;
+import org.junit.Test;
+
+import java.nio.ByteBuffer;
+import java.util.Arrays;
+
+import static org.junit.Assert.assertEquals;
+
+public class FileReferenceDataTest {
+
+    @Test
+    public void testDataBlob() {
+        String content = "blob";
+        FileReferenceData fileReferenceData =
+                new FileReferenceDataBlob(new FileReference("ref"), "foo", FileReferenceData.Type.compressed, Utf8.toBytes(content));
+        ByteBuffer byteBuffer = ByteBuffer.allocate(100);
+        assertEquals(4, fileReferenceData.nextContent(byteBuffer));
+        assertEquals(content, Utf8.toString(Arrays.copyOfRange(byteBuffer.array(), 0, 4)));
+
+        // nextContent() will always return everything for FileReferenceDataBlob, so nothing more should be read
+        assertEquals(-1, fileReferenceData.nextContent(byteBuffer));
+    }
+
+}