SERVER-30379 Add health log.

4 files changed, 247 insertions, 0 deletions

diff --git a/src/mongo/db/catalog/SConscript b/src/mongo/db/catalog/SConscript
index e39e37db406..d42ba033db3 100644
--- a/src/mongo/db/catalog/SConscript
+++ b/src/mongo/db/catalog/SConscript
@@ -40,6 +40,20 @@ env.Library(
 )
 
 env.Library(
+    target='health_log',
+    source=[
+        "health_log.cpp",
+        env.Idlc("health_log.idl")[0],
+    ],
+    LIBDEPS=[
+        "$BUILD_DIR/mongo/base",
+        "$BUILD_DIR/mongo/db/concurrency/deferred_writer",
+        "$BUILD_DIR/mongo/db/service_context",
+        "$BUILD_DIR/mongo/idl/idl_parser",
+    ],
+);
+
+env.Library(
     target='index_key_validate',
     source=[
         "index_key_validate.cpp",
@@ -205,6 +219,7 @@ env.Library(
         'collection_options',
         'database',
         'database_holder',
+        'health_log',
         'index_catalog',
         'index_catalog_entry',
         'index_create',
diff --git a/src/mongo/db/catalog/health_log.cpp b/src/mongo/db/catalog/health_log.cpp
new file mode 100644
index 00000000000..fedfec68eab
--- /dev/null
+++ b/src/mongo/db/catalog/health_log.cpp
@@ -0,0 +1,80 @@
+/**
+ *    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/catalog/health_log.h"
+#include "mongo/db/catalog/health_log_gen.h"
+#include "mongo/db/concurrency/write_conflict_exception.h"
+#include "mongo/db/db_raii.h"
+
+namespace mongo {
+
+namespace {
+const ServiceContext::Decoration<HealthLog> getHealthLog =
+    ServiceContext::declareDecoration<HealthLog>();
+
+const int64_t kDefaultHealthlogSize = 100'000'000;
+
+CollectionOptions getOptions(void) {
+    CollectionOptions options;
+    options.capped = true;
+    options.cappedSize = kDefaultHealthlogSize;
+    return options;
+}
+}
+
+HealthLog::HealthLog() : _writer(nss, getOptions(), kMaxBufferSize) {}
+
+void HealthLog::startup(void) {
+    _writer.startup(std::string("healthlog writer"));
+}
+
+void HealthLog::shutdown(void) {
+    _writer.shutdown();
+}
+
+HealthLog& HealthLog::get(ServiceContext* svcCtx) {
+    return getHealthLog(svcCtx);
+}
+
+HealthLog& HealthLog::get(OperationContext* opCtx) {
+    return getHealthLog(opCtx->getServiceContext());
+}
+
+bool HealthLog::log(const HealthLogEntry& entry) {
+    BSONObjBuilder builder;
+    OID oid;
+    oid.init();
+    builder.append("_id", oid);
+    entry.serialize(&builder);
+    return _writer.insertDocument(builder.obj());
+}
+
+const NamespaceString HealthLog::nss("local", "system.healthlog");
+}
diff --git a/src/mongo/db/catalog/health_log.h b/src/mongo/db/catalog/health_log.h
new file mode 100644
index 00000000000..84de0e215ab
--- /dev/null
+++ b/src/mongo/db/catalog/health_log.h
@@ -0,0 +1,93 @@
+/**
+ *    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.
+ */
+
+#pragma once
+
+#include "mongo/base/disallow_copying.h"
+#include "mongo/db/concurrency/deferred_writer.h"
+#include "mongo/db/service_context.h"
+
+namespace mongo {
+
+class HealthLogEntry;
+
+/**
+ * The interface to the local healthlog.
+ *
+ * This class contains facilities for creating and asynchronously writing to the local healthlog
+ * collection.  There should only be one instance of this class, initialized on startup and cleaned
+ * up on shutdown.
+ */
+class HealthLog {
+    MONGO_DISALLOW_COPYING(HealthLog);
+
+public:
+    /**
+     * Required to use HealthLog as a ServiceContext decorator.
+     *
+     * Should not be used anywhere else.
+     */
+    HealthLog();
+
+    /**
+     * The maximum size of the in-memory buffer of health-log entries, in bytes.
+     */
+    static const int64_t kMaxBufferSize = 25'000'000;
+
+    /**
+     * Start the worker thread writing the buffer to the collection.
+     */
+    void startup(void);
+
+    /**
+     * Stop the worker thread.
+     */
+    void shutdown(void);
+
+    /**
+     * The name of the collection.
+     */
+    static const NamespaceString nss;
+
+    /**
+     * Get the current context's HealthLog.
+     */
+    static HealthLog& get(ServiceContext* ctx);
+    static HealthLog& get(OperationContext* ctx);
+
+    /**
+     * Asynchronously insert the given entry.
+     *
+     * Return `false` iff there is no more space in the buffer.
+     */
+    bool log(const HealthLogEntry& entry);
+
+private:
+    DeferredWriter _writer;
+};
+}
diff --git a/src/mongo/db/catalog/health_log.idl b/src/mongo/db/catalog/health_log.idl
new file mode 100644
index 00000000000..f38bc85a72a
--- /dev/null
+++ b/src/mongo/db/catalog/health_log.idl
@@ -0,0 +1,59 @@
+# 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/>.
+#
+
+global:
+  cpp_namespace: "mongo"
+
+imports:
+  - "mongo/idl/basic_types.idl"
+
+types:
+  _id_key:
+    bson_serialization_type: any
+    description: "An _id value."
+    cpp_type: "mongo::BSONKey"
+    serializer: "mongo::BSONKey::serializeToBSON"
+    deserializer: "mongo::BSONKey::parseFromBSON"
+
+enums:
+  Severity:
+    description: "The severity of a healthlog entry."
+    type: string
+    values:
+      Info: "info"
+      Warning: "warning"
+      Error: "error"
+  Scope:
+    description: "The scope covered by a healthlog entry."
+    type: string
+    values:
+      Cluster: "cluster"
+      Node: "node"
+      Database: "database"
+      Collection: "collection"
+      Index: "index"
+      Document: "document"
+
+structs:
+  HealthLogEntry:
+    description: "An entry in system.local.healthlog."
+    fields:
+      namespace: namespacestring
+      timestamp: date
+      severity: Severity
+      msg: string
+      scope: Scope
+      operation: string
+      data: object