SERVER-28887 Cleanup KeysCollectionCacheReader/AndUpdater

1 files changed, 111 insertions, 0 deletions

diff --git a/src/mongo/db/keys_collection_cache.cpp b/src/mongo/db/keys_collection_cache.cpp
new file mode 100644
index 00000000000..0491d69397f
--- /dev/null
+++ b/src/mongo/db/keys_collection_cache.cpp
@@ -0,0 +1,111 @@
+/**
+ *    Copyright (C) 2017 MongoDB, 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/platform/basic.h"
+
+#include "mongo/db/keys_collection_cache.h"
+
+#include "mongo/db/keys_collection_client.h"
+#include "mongo/db/keys_collection_document.h"
+#include "mongo/util/mongoutils/str.h"
+
+namespace mongo {
+
+KeysCollectionCache::KeysCollectionCache(std::string purpose, KeysCollectionClient* client)
+    : _purpose(std::move(purpose)), _client(client) {}
+
+StatusWith<KeysCollectionDocument> KeysCollectionCache::refresh(OperationContext* opCtx) {
+    LogicalTime newerThanThis;
+
+    {
+        stdx::lock_guard<stdx::mutex> lk(_cacheMutex);
+        auto iter = _cache.crbegin();
+        if (iter != _cache.crend()) {
+            newerThanThis = iter->second.getExpiresAt();
+        }
+    }
+
+    auto refreshStatus = _client->getNewKeys(opCtx, _purpose, newerThanThis);
+
+    if (!refreshStatus.isOK()) {
+        return refreshStatus.getStatus();
+    }
+
+    auto& newKeys = refreshStatus.getValue();
+
+    stdx::lock_guard<stdx::mutex> lk(_cacheMutex);
+    for (auto&& key : newKeys) {
+        _cache.emplace(std::make_pair(key.getExpiresAt(), std::move(key)));
+    }
+
+    if (_cache.empty()) {
+        return {ErrorCodes::KeyNotFound, "No keys found after refresh"};
+    }
+
+    return _cache.crbegin()->second;
+}
+
+StatusWith<KeysCollectionDocument> KeysCollectionCache::getKeyById(long long keyId,
+                                                                   const LogicalTime& forThisTime) {
+    stdx::lock_guard<stdx::mutex> lk(_cacheMutex);
+
+    for (auto iter = _cache.lower_bound(forThisTime); iter != _cache.cend(); ++iter) {
+        if (iter->second.getKeyId() == keyId) {
+            return iter->second;
+        }
+    }
+
+    return {ErrorCodes::KeyNotFound,
+            str::stream() << "Cache Reader No keys found for " << _purpose
+                          << " that is valid for time: "
+                          << forThisTime.toString()
+                          << " with id: "
+                          << keyId};
+}
+
+StatusWith<KeysCollectionDocument> KeysCollectionCache::getKey(const LogicalTime& forThisTime) {
+    stdx::lock_guard<stdx::mutex> lk(_cacheMutex);
+
+    auto iter = _cache.upper_bound(forThisTime);
+
+    if (iter == _cache.cend()) {
+        return {ErrorCodes::KeyNotFound,
+                str::stream() << "No key found that is valid for " << forThisTime.toString()};
+    }
+
+    return iter->second;
+}
+
+void KeysCollectionCache::resetCache() {
+    // keys that read with non majority readConcern level can be rolled back.
+    if (!_client->supportsMajorityReads()) {
+        _cache.clear();
+    }
+}
+
+}  // namespace mongo