Support for restarting a persistent cluster.

Option --cluster-size=N: members wait for N members before recovering store.
Stores marked as clean/dirty. Automatically recover from clean store on restart.
Stores marked with UUID to detect errors.

Not yet implemented: consistency checks, manual recovery from all dirty stores.


git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk/qpid@883842 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 96 insertions, 0 deletions

diff --git a/cpp/src/qpid/cluster/StoreStatus.cpp b/cpp/src/qpid/cluster/StoreStatus.cpp
new file mode 100644
index 0000000000..1c5f581ea1
--- /dev/null
+++ b/cpp/src/qpid/cluster/StoreStatus.cpp
@@ -0,0 +1,96 @@
+/*
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ *
+ */
+#include "StoreStatus.h"
+#include "qpid/Exception.h"
+#include <boost/filesystem/path.hpp>
+#include <boost/filesystem/fstream.hpp>
+#include <boost/filesystem/operations.hpp>
+#include <fstream>
+
+namespace qpid {
+namespace cluster {
+
+using framing::Uuid;
+using namespace framing::cluster;
+using namespace boost::filesystem;
+
+StoreStatus::StoreStatus(const std::string& d)
+    : state(STORE_STATE_NO_STORE), dataDir(d)
+{}
+
+namespace {
+
+const char* SUBDIR="cluster";
+const char* START_FILE="start";
+const char* STOP_FILE="stop";
+
+Uuid loadUuid(const path& path) {
+    Uuid ret;
+    if (exists(path)) {
+        ifstream i(path);
+        i >> ret;
+    }
+    return ret;
+}
+
+void saveUuid(const path& path, const Uuid& uuid) {
+    ofstream o(path);
+    o << uuid;
+}
+
+} // namespace
+
+
+void StoreStatus::load() {
+    path dir = path(dataDir)/SUBDIR;
+    create_directory(dir);
+    start = loadUuid(dir/START_FILE);
+    stop = loadUuid(dir/STOP_FILE);
+
+    if (start && stop) state = STORE_STATE_CLEAN_STORE;
+    else if (start) state = STORE_STATE_DIRTY_STORE;
+    else state = STORE_STATE_EMPTY_STORE;
+}
+
+void StoreStatus::save() {
+    path dir = path(dataDir)/SUBDIR;
+    create_directory(dir);
+    saveUuid(dir/START_FILE, start);
+    saveUuid(dir/STOP_FILE, stop);
+}
+
+void StoreStatus::dirty(const Uuid& start_) {
+    start = start_;
+    stop = Uuid();
+    state = STORE_STATE_DIRTY_STORE;
+    save();
+}
+
+void StoreStatus::clean(const Uuid& stop_) {
+    assert(start);              // FIXME aconway 2009-11-20: exception?
+    assert(stop_);
+    state = STORE_STATE_CLEAN_STORE;
+    stop = stop_;
+    save();
+}
+
+}} // namespace qpid::cluster
+