SERVER-8920: Add new fields to dbStats command for pdfile version

2 files changed, 19 insertions, 0 deletions

diff --git a/jstests/stats.js b/jstests/stats.js
index 26de644f02c..33c08686e83 100644
--- a/jstests/stats.js
+++ b/jstests/stats.js
@@ -7,3 +7,14 @@ t.save( { a : 1 } );
 assert.lt( 0 , t.dataSize() , "A" );
 assert.lt( t.dataSize() , t.storageSize() , "B" );
 assert.lt( 0 , t.totalIndexSize() , "C" );
+
+var stats = db.stats();
+assert.gt( stats.fileSize, 0 );
+assert.eq( stats.dataFileVersion.major, 4 );
+assert.eq( stats.dataFileVersion.minor, 5 );
+
+db.getSiblingDB( "emptydatabase" ).dropDatabase();
+var statsEmptyDB = db.getSiblingDB( "emptydatabase" ).stats();
+assert.eq( statsEmptyDB.fileSize, 0 );
+assert.eq( {}, statsEmptyDB.dataFileVersion );
+
diff --git a/src/mongo/db/dbcommands.cpp b/src/mongo/db/dbcommands.cpp
index 045df983eb9..b06ff459847 100644
--- a/src/mongo/db/dbcommands.cpp
+++ b/src/mongo/db/dbcommands.cpp
@@ -1463,6 +1463,14 @@ namespace mongo {
             if( d )
                 result.appendNumber( "nsSizeMB", (int) d->namespaceIndex.fileLength() / 1024 / 1024 );
 
+            BSONObjBuilder dataFileVersion( result.subobjStart( "dataFileVersion" ) );
+            if ( d && !d->isEmpty() ) {
+                DataFileHeader* header = d->getFile( 0 )->getHeader();
+                dataFileVersion.append( "major", header->version );
+                dataFileVersion.append( "minor", header->versionMinor );
+            }
+            dataFileVersion.done();
+
             return true;
         }
     } cmdDBStats;