questions about SSTableExport/Import

[aaron morton]

I was trying to help this guy 
http://www.mail-archive.com/u...@cassandra.apache.org/msg07297.html who seemed 
to have troubles loading a json file. And I started taking a look at 
SSTableExport and SSTableImport.

SSTableExport does not encode any information about the Column sub type 
(ExpiringColumn or DeletedColumn). It records isMarkedForDelete(), the 
timestamp and the localDeletionTime as the col value if its a DeletedColumn. 
SSTableImport then calls either cf.addColumn() or cf.addTombstone() based on 
the deleted flag. 

First question is is the code in SSTableImport.addToStandardCF() correct to 
call cf.addColumn() if when the column was serialised it was 
isMarkedForDelete() ?

Next is it OK to lose the fact that a column is an ExpiringColumn (and its ttl) 
when it's exported to json? 

On my local machine I modified the unit test for SSTableExport as below and the 
assertion that the col was not returned failed.

Thanks
Aaron

diff --git a/test/unit/org/apache/cassandra/tools/SSTableExportTest.java 
b/test/unit/org/apache/cassandra/tools/SSTableExportTest.java
index 6f79f62..53d2a9c 100644
--- a/test/unit/org/apache/cassandra/tools/SSTableExportTest.java
+++ b/test/unit/org/apache/cassandra/tools/SSTableExportTest.java
@@ -179,6 +179,7 @@ public class SSTableExportTest extends SchemaLoader
         
         // Add rowA
         cfamily.addColumn(new QueryPath("Standard1", null, 
ByteBufferUtil.bytes("name")), ByteBufferUtil.bytes("val"), 1);
+        cfamily.addColumn(new QueryPath("Standard1", null, 
ByteBufferUtil.bytes("ttl")), ByteBufferUtil.bytes("val"), 1, 1);
         writer.append(Util.dk("rowA"), cfamily);
         cfamily.clear();
 
@@ -187,6 +188,15 @@ public class SSTableExportTest extends SchemaLoader
         writer.append(Util.dk("rowExclude"), cfamily);
         cfamily.clear();
 
+        //make sure the ttl col has expired
+        try
+        {
+            Thread.sleep(1500);
+        }
+        catch (InterruptedException e)
+        {
+            throw new AssertionError(e);
+        }
         SSTableReader reader = writer.closeAndOpenReader();
         
         // Export to JSON and verify
@@ -203,6 +213,11 @@ public class SSTableExportTest extends SchemaLoader
         assertTrue(cf != null);
         
assertTrue(cf.getColumn(ByteBufferUtil.bytes("name")).value().equals(ByteBuffer.wrap(hexToBytes("76616c"))));
 
+        qf = QueryFilter.getNamesFilter(Util.dk("rowA"), new 
QueryPath("Standard1", null, null), ByteBufferUtil.bytes("ttl"));
+        cf = qf.getSSTableColumnIterator(reader).getColumnFamily();
+        assertTrue(cf != null);
+        assertTrue(cf.getColumn(ByteBufferUtil.bytes("ttl")) == null);
+