SERVER-28495 FTDC for MongoS

1 files changed, 153 insertions, 0 deletions

diff --git a/src/mongo/db/ftdc/ftdc_mongos.cpp b/src/mongo/db/ftdc/ftdc_mongos.cpp
new file mode 100644
index 00000000000..bdacaa7b6e1
--- /dev/null
+++ b/src/mongo/db/ftdc/ftdc_mongos.cpp
@@ -0,0 +1,153 @@
+/**
+ * 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.
+ */
+#define MONGO_LOG_DEFAULT_COMPONENT ::mongo::logger::LogComponent::kFTDC
+
+#include "mongo/platform/basic.h"
+
+#include "mongo/db/ftdc/ftdc_mongos.h"
+
+#include <boost/filesystem.hpp>
+
+#include "mongo/db/ftdc/controller.h"
+#include "mongo/db/ftdc/ftdc_server.h"
+#include "mongo/db/server_parameters.h"
+#include "mongo/stdx/thread.h"
+#include "mongo/util/log.h"
+
+namespace mongo {
+
+namespace {
+
+/**
+ * Expose diagnosticDataCollectionDirectoryPath set parameter to specify the MongoS FTDC path.
+ */
+class ExportedFTDCDirectoryPathParameter : public ServerParameter {
+public:
+    ExportedFTDCDirectoryPathParameter()
+        : ServerParameter(ServerParameterSet::getGlobal(),
+                          "diagnosticDataCollectionDirectoryPath",
+                          true,
+                          true) {}
+
+
+    void append(OperationContext* opCtx, BSONObjBuilder& b, const std::string& name) final {
+        stdx::lock_guard<stdx::mutex> guard(_lock);
+        b.append(name, _path.generic_string());
+    }
+
+    Status set(const BSONElement& newValueElement) {
+        if (newValueElement.type() != String) {
+            return Status(ErrorCodes::BadValue,
+                          "diagnosticDataCollectionDirectoryPath only supports type string");
+        }
+
+        std::string str = newValueElement.str();
+        return setFromString(str);
+    }
+
+    Status setFromString(const std::string& str) final {
+        stdx::lock_guard<stdx::mutex> guard(_lock);
+
+        FTDCController* controller = nullptr;
+
+        if (hasGlobalServiceContext()) {
+            controller = FTDCController::get(getGlobalServiceContext());
+        }
+
+        if (controller) {
+            Status s = controller->setDirectory(str);
+            if (!s.isOK()) {
+                return s;
+            }
+        }
+
+        _path = str;
+
+        return Status::OK();
+    }
+
+    boost::filesystem::path getDirectory() {
+        stdx::lock_guard<stdx::mutex> guard(_lock);
+        return _path;
+    }
+
+    void setDirectory(boost::filesystem::path& path) {
+        stdx::lock_guard<stdx::mutex> guard(_lock);
+        _path = path;
+    }
+
+private:
+    // Lock to guard _path
+    stdx::mutex _lock;
+
+    // Directory location of ftdc files, guarded by _lock
+    boost::filesystem::path _path;
+} exportedFTDCDirectoryPathParameter;
+
+void registerMongoSCollectors(FTDCController* controller) {
+    // PoolStats
+    controller->addPeriodicCollector(stdx::make_unique<FTDCSimpleInternalCommandCollector>(
+        "connPoolStats", "connPoolStats", "", BSON("connPoolStats" << 1)));
+}
+
+}  // namespace
+
+void startMongoSFTDC() {
+    // Get the path to use for FTDC:
+    // 1. Check if the user set one.
+    // 2. If not, check if the user has a logpath and derive one.
+    // 3. Otherwise, tell the user FTDC cannot run.
+
+    // Only attempt to enable FTDC if we have a path to log files to.
+    FTDCStartMode startMode = FTDCStartMode::kStart;
+    auto directory = exportedFTDCDirectoryPathParameter.getDirectory();
+
+    if (directory.empty()) {
+        if (serverGlobalParams.logpath.empty()) {
+            warning() << "FTDC is disabled because neither '--logpath' nor set parameter "
+                         "'diagnosticDataCollectionDirectoryPath' are specified.";
+            startMode = FTDCStartMode::kSkipStart;
+        } else {
+            directory = FTDCUtil::getMongoSPath(serverGlobalParams.logpath);
+
+            // Update the server parameter with the computed path.
+            // Note: If the computed FTDC directory conflicts with an existing file, then FTDC will
+            // warn about the conflict, and not startup. It will not terminate MongoS in this
+            // situation.
+            exportedFTDCDirectoryPathParameter.setDirectory(directory);
+        }
+    }
+
+    startFTDC(directory, startMode, registerMongoSCollectors);
+}
+
+void stopMongoSFTDC() {
+    stopFTDC();
+}
+
+}  // namespace mongo