SERVER-41360 Created DiagnosticInfo class

4 files changed, 200 insertions, 0 deletions

diff --git a/src/mongo/util/SConscript b/src/mongo/util/SConscript
index 59007e2c9f4..30089944be2 100644
--- a/src/mongo/util/SConscript
+++ b/src/mongo/util/SConscript
@@ -468,6 +468,28 @@ env.CppUnitTest(
     ],
 )
 
+env.Library(
+    target='diagnostic_info',
+    source= [
+        'diagnostic_info.cpp',
+    ],
+    LIBDEPS=[
+        '$BUILD_DIR/mongo/base',
+        "$BUILD_DIR/mongo/db/service_context",
+    ],
+)
+
+env.CppUnitTest(
+    target='diagnostic_info_test',
+    source=[
+        'diagnostic_info_test.cpp'
+        ],
+    LIBDEPS=[
+        'diagnostic_info',
+        'clock_source_mock',
+        ]
+)
+
 env.Benchmark(
     target='clock_source_bm',
     source=[
diff --git a/src/mongo/util/diagnostic_info.cpp b/src/mongo/util/diagnostic_info.cpp
new file mode 100644
index 00000000000..e74b0968233
--- /dev/null
+++ b/src/mongo/util/diagnostic_info.cpp
@@ -0,0 +1,41 @@
+/**
+ *    Copyright (C) 2018-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 "mongo/platform/basic.h"
+
+#include "mongo/util/diagnostic_info.h"
+
+#include "mongo/util/clock_source.h"
+
+namespace mongo {
+
+DiagnosticInfo takeDiagnosticInfo(const StringData& captureName) {
+    return DiagnosticInfo(getGlobalServiceContext()->getFastClockSource()->now(), captureName);
+}
+}  // namespace mongo
diff --git a/src/mongo/util/diagnostic_info.h b/src/mongo/util/diagnostic_info.h
new file mode 100644
index 00000000000..9685135b0d2
--- /dev/null
+++ b/src/mongo/util/diagnostic_info.h
@@ -0,0 +1,75 @@
+/**
+ *    Copyright (C) 2018-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/base/string_data.h"
+#include "mongo/db/service_context.h"
+#include "mongo/util/time_support.h"
+
+namespace mongo {
+
+/**
+ * DiagnosticInfo keeps track of diagnostic information such as a developer provided
+ * name, the time when a lock was first acquired, and a partial caller call stack.
+ */
+class DiagnosticInfo {
+public:
+    virtual ~DiagnosticInfo() = default;
+    DiagnosticInfo(const DiagnosticInfo&) = delete;
+    DiagnosticInfo& operator=(const DiagnosticInfo&) = delete;
+    DiagnosticInfo(DiagnosticInfo&&) = default;
+    DiagnosticInfo& operator=(DiagnosticInfo&&) = default;
+
+    Date_t getTimestamp() {
+        return _timestamp;
+    }
+
+    StringData getCaptureName() {
+        return _captureName;
+    }
+
+    friend DiagnosticInfo takeDiagnosticInfo(const StringData& captureName);
+
+private:
+    Date_t _timestamp;
+    StringData _captureName;
+
+
+    DiagnosticInfo(const Date_t& timestamp, const StringData& captureName)
+        : _timestamp(timestamp), _captureName(captureName) {}
+};
+
+/**
+ * Captures the diagnostic information based on the caller's context.
+ */
+DiagnosticInfo takeDiagnosticInfo(const StringData& captureName);
+
+
+}  // namespace monogo
diff --git a/src/mongo/util/diagnostic_info_test.cpp b/src/mongo/util/diagnostic_info_test.cpp
new file mode 100644
index 00000000000..c12155b98d2
--- /dev/null
+++ b/src/mongo/util/diagnostic_info_test.cpp
@@ -0,0 +1,62 @@
+/**
+ *    Copyright (C) 2018-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 <string>
+
+#include "mongo/unittest/unittest.h"
+#include "mongo/util/clock_source_mock.h"
+#include "mongo/util/diagnostic_info.h"
+
+namespace mongo {
+TEST(DiagnosticInfo, BasicSingleThread) {
+    // set up serviceContext and clock source
+    auto serviceContext = ServiceContext::make();
+    auto clockSource = std::make_unique<ClockSourceMock>();
+    auto clockSourcePointer = clockSource.get();
+    serviceContext->setFastClockSource(std::move(clockSource));
+    setGlobalServiceContext(std::move(serviceContext));
+
+    // take the initial diagnostic info
+    DiagnosticInfo capture1 = takeDiagnosticInfo("capture1"_sd);
+    ASSERT_EQ(capture1.getCaptureName(), "capture1");
+
+    // mock time advancing and check that the current time is greater than capture1's timestamp
+    clockSourcePointer->advance(Seconds(1));
+    ASSERT_LT(capture1.getTimestamp(), clockSourcePointer->now());
+
+    // take a second diagnostic capture and compare its fields to the first
+    DiagnosticInfo capture2 = takeDiagnosticInfo("capture2"_sd);
+    ASSERT_LT(capture1.getTimestamp(), capture2.getTimestamp());
+    ASSERT_EQ(capture1.getCaptureName(), "capture1");
+    ASSERT_EQ(capture2.getCaptureName(), "capture2");
+
+    clockSourcePointer->advance(Seconds(1));
+    ASSERT_LT(capture2.getTimestamp(), clockSourcePointer->now());
+}
+}