SERVER-24616 Add new getDiagnosticData command

7 files changed, 250 insertions, 1 deletions

diff --git a/src/mongo/db/ftdc/SConscript b/src/mongo/db/ftdc/SConscript
index 20294484bb4..ba630ba68c1 100644
--- a/src/mongo/db/ftdc/SConscript
+++ b/src/mongo/db/ftdc/SConscript
@@ -38,6 +38,7 @@ if env.TargetOSIs('linux'):
 env.Library(
     target='ftdc_mongod',
     source=[
+        'ftdc_commands.cpp',
         'ftdc_mongod.cpp',
         'ftdc_system_stats.cpp',
     ],
diff --git a/src/mongo/db/ftdc/controller.cpp b/src/mongo/db/ftdc/controller.cpp
index 3639be9ebed..bf3e80437be 100644
--- a/src/mongo/db/ftdc/controller.cpp
+++ b/src/mongo/db/ftdc/controller.cpp
@@ -99,6 +99,13 @@ void FTDCController::addOnRotateCollector(std::unique_ptr<FTDCCollectorInterface
     }
 }
 
+BSONObj FTDCController::getMostRecentPeriodicDocument() {
+    {
+        stdx::lock_guard<stdx::mutex> lock(_mutex);
+        return _mostRecentPeriodicDocument.getOwned();
+    }
+}
+
 void FTDCController::start() {
     log() << "Initializing full-time diagnostic data capture with directory '"
           << _path.generic_string() << "'";
@@ -211,6 +218,12 @@ void FTDCController::doLoop() {
                     client, std::get<0>(collectSample), std::get<1>(collectSample));
 
                 uassertStatusOK(s);
+
+                // Store a reference to the most recent document from the periodic collectors
+                {
+                    stdx::lock_guard<stdx::mutex> lock(_mutex);
+                    _mostRecentPeriodicDocument = std::get<0>(collectSample);
+                }
             }
         }
     } catch (...) {
diff --git a/src/mongo/db/ftdc/controller.h b/src/mongo/db/ftdc/controller.h
index 3db82b6b171..44b5e838506 100644
--- a/src/mongo/db/ftdc/controller.h
+++ b/src/mongo/db/ftdc/controller.h
@@ -43,6 +43,8 @@
 
 namespace mongo {
 
+class ServiceContext;
+
 /**
  * Responsible for periodic collection of samples, writing them to disk,
  * and rotation.
@@ -118,6 +120,16 @@ public:
      */
     void stop();
 
+    /**
+     * Get the FTDCController from ServiceContext.
+     */
+    static FTDCController* get(ServiceContext* serviceContext);
+
+    /**
+     * Get a reference to most recent document from the periodic collectors.
+     */
+    BSONObj getMostRecentPeriodicDocument();
+
 private:
     /**
      * Do periodic statistics collection, and all other work on the background thread.
@@ -162,7 +174,7 @@ private:
     // Directory to store files
     const boost::filesystem::path _path;
 
-    // Mutex to protect the condvar, and configuration changes.
+    // Mutex to protect the condvar, configuration changes, and most recent periodic document.
     stdx::mutex _mutex;
     stdx::condition_variable _condvar;
 
@@ -176,6 +188,10 @@ private:
     // Set of periodic collectors
     FTDCCollectorCollection _periodicCollectors;
 
+    // Last seen sample document from periodic collectors
+    // Owned
+    BSONObj _mostRecentPeriodicDocument;
+
     // Set of file rotation collectors
     FTDCCollectorCollection _rotateCollectors;
 
diff --git a/src/mongo/db/ftdc/ftdc_commands.cpp b/src/mongo/db/ftdc/ftdc_commands.cpp
new file mode 100644
index 00000000000..8fea20ee1da
--- /dev/null
+++ b/src/mongo/db/ftdc/ftdc_commands.cpp
@@ -0,0 +1,115 @@
+/**
+ * Copyright (C) 2016 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/base/init.h"
+#include "mongo/db/auth/action_type.h"
+#include "mongo/db/auth/authorization_session.h"
+#include "mongo/db/client.h"
+#include "mongo/db/commands.h"
+#include "mongo/db/ftdc/controller.h"
+#include "mongo/db/jsobj.h"
+#include "mongo/db/operation_context.h"
+
+namespace mongo {
+namespace {
+
+/**
+ * Get the most recent document FTDC collected from its periodic collectors.
+ *
+ * Document will be empty if FTDC has never run.
+ */
+class GetDiagnosticDataCommand final : public Command {
+public:
+    GetDiagnosticDataCommand() : Command("getDiagnosticData") {}
+
+    bool adminOnly() const override {
+        return true;
+    }
+
+    void help(std::stringstream& help) const override {
+        help << "get latest diagnostic data collection snapshot";
+    }
+
+    bool slaveOk() const override {
+        return true;
+    }
+
+    bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
+
+    Status checkAuthForCommand(ClientBasic* client,
+                               const std::string& dbname,
+                               const BSONObj& cmdObj) override {
+
+        if (!AuthorizationSession::get(client)->isAuthorizedForActionsOnResource(
+                ResourcePattern::forClusterResource(), ActionType::serverStatus)) {
+            return Status(ErrorCodes::Unauthorized, "Unauthorized");
+        }
+
+        if (!AuthorizationSession::get(client)->isAuthorizedForActionsOnResource(
+                ResourcePattern::forClusterResource(), ActionType::replSetGetStatus)) {
+            return Status(ErrorCodes::Unauthorized, "Unauthorized");
+        }
+
+        if (!AuthorizationSession::get(client)->isAuthorizedForActionsOnResource(
+                ResourcePattern::forExactNamespace(NamespaceString("local", "oplog.rs")),
+                ActionType::collStats)) {
+            return Status(ErrorCodes::Unauthorized, "Unauthorized");
+        }
+
+        return Status::OK();
+    }
+
+    bool run(OperationContext* txn,
+             const std::string& db,
+             BSONObj& cmdObj,
+             int options,
+             std::string& errmsg,
+             BSONObjBuilder& result) override {
+
+        result.append(
+            "data", FTDCController::get(txn->getServiceContext())->getMostRecentPeriodicDocument());
+
+        return true;
+    }
+};
+
+Command* ftdcCommand;
+
+MONGO_INITIALIZER(CreateDiagnosticDataCommand)(InitializerContext* context) {
+    ftdcCommand = new GetDiagnosticDataCommand();
+
+    return Status::OK();
+}
+
+}  // namespace
+
+}  // namespace mongo
diff --git a/src/mongo/db/ftdc/ftdc_mongod.cpp b/src/mongo/db/ftdc/ftdc_mongod.cpp
index 6cbd781de3c..0f0ea5a49df 100644
--- a/src/mongo/db/ftdc/ftdc_mongod.cpp
+++ b/src/mongo/db/ftdc/ftdc_mongod.cpp
@@ -28,6 +28,8 @@
 
 #include "mongo/platform/basic.h"
 
+#include "mongo/db/ftdc/ftdc_mongod.h"
+
 #include <boost/filesystem.hpp>
 #include <fstream>
 #include <memory>
@@ -304,6 +306,8 @@ void startFTDC() {
 
     // Install periodic collectors
     // These are collected on the period interval in FTDCConfig.
+    // NOTE: For each command here, there must be an equivalent privilege check in
+    // GetDiagnosticDataCommand
 
     // CmdServerStatus
     controller->addPeriodicCollector(stdx::make_unique<FTDCSimpleInternalCommandCollector>(
@@ -359,4 +363,8 @@ void stopFTDC() {
     }
 }
 
+FTDCController* FTDCController::get(ServiceContext* serviceContext) {
+    return getFTDCController(serviceContext).get();
+}
+
 }  // namespace mongo
diff --git a/src/mongo/s/commands/SConscript b/src/mongo/s/commands/SConscript
index 52e20b68ad1..27e8592d881 100644
--- a/src/mongo/s/commands/SConscript
+++ b/src/mongo/s/commands/SConscript
@@ -34,6 +34,7 @@ env.Library(
         'cluster_find_and_modify_cmd.cpp',
         'cluster_flush_router_config_cmd.cpp',
         'cluster_fsync_cmd.cpp',
+        'cluster_ftdc_commands.cpp',
         'cluster_get_last_error_cmd.cpp',
         'cluster_get_prev_error_cmd.cpp',
         'cluster_get_shard_version_cmd.cpp',
diff --git a/src/mongo/s/commands/cluster_ftdc_commands.cpp b/src/mongo/s/commands/cluster_ftdc_commands.cpp
new file mode 100644
index 00000000000..bfe339198c4
--- /dev/null
+++ b/src/mongo/s/commands/cluster_ftdc_commands.cpp
@@ -0,0 +1,95 @@
+/**
+ * Copyright (C) 2016 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/base/init.h"
+#include "mongo/db/auth/action_type.h"
+#include "mongo/db/auth/authorization_session.h"
+#include "mongo/db/client.h"
+#include "mongo/db/commands.h"
+#include "mongo/db/ftdc/controller.h"
+#include "mongo/db/jsobj.h"
+#include "mongo/db/operation_context.h"
+
+namespace mongo {
+namespace {
+
+/**
+ * getDiagnosticData is a MongoD only command. We implement in MongoS to give users a better error
+ * message.
+ */
+class GetDiagnosticDataCommand final : public Command {
+public:
+    GetDiagnosticDataCommand() : Command("getDiagnosticData") {}
+
+    bool adminOnly() const override {
+        return true;
+    }
+
+    void help(std::stringstream& help) const override {
+        help << "get latest diagnostic data collection snapshot";
+    }
+
+    bool slaveOk() const override {
+        return true;
+    }
+
+    bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
+
+    Status checkAuthForCommand(ClientBasic* client,
+                               const std::string& dbname,
+                               const BSONObj& cmdObj) override {
+        return Status::OK();
+    }
+
+    bool run(OperationContext* txn,
+             const std::string& db,
+             BSONObj& cmdObj,
+             int options,
+             std::string& errmsg,
+             BSONObjBuilder& result) override {
+
+        errmsg = "getDiagnosticData not allowed through mongos";
+
+        return false;
+    }
+};
+
+Command* ftdcCommand;
+
+MONGO_INITIALIZER(CreateDiagnosticDataCommand)(InitializerContext* context) {
+    ftdcCommand = new GetDiagnosticDataCommand();
+
+    return Status::OK();
+}
+
+}  // namespace
+}  // namespace mongo