SERVER-41498 Create ReplicationMetrics class

4 files changed, 147 insertions, 1 deletions

diff --git a/src/mongo/db/repl/SConscript b/src/mongo/db/repl/SConscript
index b1b7b1c9cb7..520d3b95ec6 100644
--- a/src/mongo/db/repl/SConscript
+++ b/src/mongo/db/repl/SConscript
@@ -1354,3 +1354,18 @@ env.CppUnitTest(
         'databases_cloner',
     ],
 )
+
+env.Library(
+    target='replication_metrics',
+    source=[
+        'replication_metrics.cpp',
+        env.Idlc('replication_metrics.idl')[0],
+    ],
+    LIBDEPS=[
+        '$BUILD_DIR/mongo/base',
+    ],
+    LIBDEPS_PRIVATE=[
+        '$BUILD_DIR/mongo/db/commands/server_status',
+        '$BUILD_DIR/mongo/db/service_context',
+    ],
+)
\ No newline at end of file
diff --git a/src/mongo/db/repl/replication_metrics.cpp b/src/mongo/db/repl/replication_metrics.cpp
new file mode 100644
index 00000000000..1c1c4075d68
--- /dev/null
+++ b/src/mongo/db/repl/replication_metrics.cpp
@@ -0,0 +1,55 @@
+/**
+ *    Copyright (C) 2019-present MongoDB, Inc.
+ *
+ *    This program is free software: you can redistribute it and/or modify
+ *    it under the terms of the Server Side Public License, version 1,
+ *    as published by MongoDB, Inc.
+ *
+ *    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
+ *    Server Side Public License for more details.
+ *
+ *    You should have received a copy of the Server Side Public License
+ *    along with this program. If not, see
+ *    <http://www.mongodb.com/licensing/server-side-public-license>.
+ *
+ *    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 Server Side 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 "src/mongo/db/repl/replication_metrics.h"
+
+#include "mongo/db/commands/server_status.h"
+
+namespace mongo {
+namespace repl {
+
+namespace {
+static const auto getReplicationMetrics = ServiceContext::declareDecoration<ReplicationMetrics>();
+}  // namespace
+
+ReplicationMetrics& ReplicationMetrics::get(ServiceContext* svc) {
+    return getReplicationMetrics(svc);
+}
+
+ReplicationMetrics& ReplicationMetrics::get(OperationContext* opCtx) {
+    return get(opCtx->getServiceContext());
+}
+
+class ReplicationMetrics::ElectionMetricsSSS : public ServerStatusSection {
+public:
+    ElectionMetricsSSS() : ServerStatusSection("electionMetrics") {}
+} electionMetricsSSS;
+
+}  // namespace repl
+}  // namespace mongo
diff --git a/src/mongo/db/repl/replication_metrics.h b/src/mongo/db/repl/replication_metrics.h
new file mode 100644
index 00000000000..7012f4802cf
--- /dev/null
+++ b/src/mongo/db/repl/replication_metrics.h
@@ -0,0 +1,60 @@
+/**
+ *    Copyright (C) 2019-present MongoDB, Inc.
+ *
+ *    This program is free software: you can redistribute it and/or modify
+ *    it under the terms of the Server Side Public License, version 1,
+ *    as published by MongoDB, Inc.
+ *
+ *    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
+ *    Server Side Public License for more details.
+ *
+ *    You should have received a copy of the Server Side Public License
+ *    along with this program. If not, see
+ *    <http://www.mongodb.com/licensing/server-side-public-license>.
+ *
+ *    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 Server Side 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.
+ */
+
+#pragma once
+
+#include "mongo/db/repl/replication_metrics_gen.h"
+#include "mongo/db/service_context.h"
+#include "mongo/stdx/mutex.h"
+
+namespace mongo {
+namespace repl {
+
+/**
+ * A service context decoration that stores metrics related to elections and replication health.
+ */
+class ReplicationMetrics {
+public:
+    static ReplicationMetrics& get(ServiceContext* svc);
+    static ReplicationMetrics& get(OperationContext* opCtx);
+
+    ReplicationMetrics();
+    ~ReplicationMetrics();
+
+private:
+    class ElectionMetricsSSS;
+
+    mutable stdx::mutex _mutex;
+    ElectionMetrics _electionMetrics;
+    ElectionCandidateMetrics _electionCandidateMetrics;
+    ElectionParticipantMetrics _electionParticipantMetrics;
+};
+
+}  // namespace repl
+}  // namespace mongo
diff --git a/src/mongo/db/repl/replication_metrics.idl b/src/mongo/db/repl/replication_metrics.idl
index 043935596a9..566d2ee665b 100644
--- a/src/mongo/db/repl/replication_metrics.idl
+++ b/src/mongo/db/repl/replication_metrics.idl
@@ -39,10 +39,26 @@ imports:
 structs:
     ElectionMetrics:
         description: "Stores metrics related to all the elections a node has called"
+        strict: true
+        fields:
+            numStepUpsRequested:
+                description: "Number of elections this node has called due to step up requests"
+                type: int
+        
         
     ElectionCandidateMetrics:
         description: "Stores metrics that are specific to the last election in which the node was a 
                       candidate"
+        strict: true
+        fields:
+            priorityAtElection:
+                description: "The node's priority at the time of the election"
+                type: double
 
     ElectionParticipantMetrics:
-        description: "Stores metrics that are specific to the last election in which the node voted"
\ No newline at end of file
+        description: "Stores metrics that are specific to the last election in which the node voted"
+        strict: true
+        fields:
+            priorityAtElection:
+                description: "The node's priority at the time of the election"
+                type: double