SERVER-6552 implement resync command for replicaset members

1 files changed, 112 insertions, 0 deletions

diff --git a/src/mongo/db/repl/resync.cpp b/src/mongo/db/repl/resync.cpp
new file mode 100644
index 00000000000..8bdcca2594b
--- /dev/null
+++ b/src/mongo/db/repl/resync.cpp
@@ -0,0 +1,112 @@
+/**
+*    Copyright (C) 2008 10gen Inc.
+*
+*    This program is free software: you can redistribute it and/or  modify
+*    it under the terms of the GNU Affero General Public License, version 3,
+*    as published by the Free Software Foundation.
+*
+*    This program is distributed in the hope that it will be useful,
+*    but WITHOUT ANY WARRANTY; without even the implied warranty of
+*    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+*    GNU Affero General Public License for more details.
+*
+*    You should have received a copy of the GNU Affero General Public License
+*    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*
+*    As a special exception, the copyright holders give permission to link the
+*    code of portions of this program with the OpenSSL library under certain
+*    conditions as described in each individual source file and distribute
+*    linked combinations including the program with the OpenSSL library. You
+*    must comply with the GNU Affero General Public License in all respects for
+*    all of the code used other than as permitted herein. If you modify file(s)
+*    with this exception, you may extend this exception to your version of the
+*    file(s), but you are not obligated to do so. If you do not wish to do so,
+*    delete this exception statement from your version. If you delete this
+*    exception statement from all source files in the program, then also delete
+*    it in the license file.
+*/
+
+#include "mongo/db/commands.h"
+#include "mongo/db/repl/master_slave.h"  // replSettings
+#include "mongo/db/repl/replication_server_status.h"  // replSettings
+#include "mongo/db/repl/rs.h" // replLocalAuth()
+
+namespace mongo {
+
+    // operator requested resynchronization of replication (on a slave or secondary). {resync: 1}
+    class CmdResync : public Command {
+    public:
+        virtual bool slaveOk() const {
+            return true;
+        }
+        virtual bool adminOnly() const {
+            return true;
+        }
+        virtual bool logTheOp() { return false; }
+        virtual bool lockGlobally() const { return true; }
+        virtual LockType locktype() const { return WRITE; }
+        virtual void addRequiredPrivileges(const std::string& dbname,
+                                           const BSONObj& cmdObj,
+                                           std::vector<Privilege>* out) {
+            ActionSet actions;
+            actions.addAction(ActionType::resync);
+            out->push_back(Privilege(ResourcePattern::forClusterResource(), actions));
+        }
+
+        void help(stringstream& h) const {
+            h << "resync (from scratch) a stale slave or replica set secondary node.\n";
+        }
+
+        CmdResync() : Command("resync") { }
+        virtual bool run(const string&,
+                         BSONObj& cmdObj,
+                         int,
+                         string& errmsg,
+                         BSONObjBuilder& result,
+                         bool fromRepl) {
+            if (replSettings.usingReplSets()) {
+                if (theReplSet->isPrimary()) {
+                    errmsg = "primaries cannot resync";
+                    return false;
+                }
+                return theReplSet->resync(errmsg);
+            }
+
+            // below this comment pertains only to master/slave replication
+            if ( cmdObj.getBoolField( "force" ) ) {
+                if ( !waitForSyncToFinish( errmsg ) )
+                    return false;
+                replAllDead = "resync forced";
+            }
+            if ( !replAllDead ) {
+                errmsg = "not dead, no need to resync";
+                return false;
+            }
+            if ( !waitForSyncToFinish( errmsg ) )
+                return false;
+
+            ReplSource::forceResyncDead( "client" );
+            result.append( "info", "triggered resync for all sources" );
+            return true;
+        }
+        bool waitForSyncToFinish( string &errmsg ) const {
+            // Wait for slave thread to finish syncing, so sources will be be
+            // reloaded with new saved state on next pass.
+            Timer t;
+            while ( 1 ) {
+                if ( syncing == 0 || t.millis() > 30000 )
+                    break;
+                {
+                    Lock::TempRelease t;
+                    relinquishSyncingSome = 1;
+                    sleepmillis(1);
+                }
+            }
+            if ( syncing ) {
+                errmsg = "timeout waiting for sync() to finish";
+                return false;
+            }
+            return true;
+        }
+    } cmdResync;
+}