SERVER-38450 Convert global conn pool options to IDL

3 files changed, 101 insertions, 23 deletions

diff --git a/src/mongo/client/SConscript b/src/mongo/client/SConscript
index 0b76fa83d1b..8deaaa5aaec 100644
--- a/src/mongo/client/SConscript
+++ b/src/mongo/client/SConscript
@@ -183,6 +183,7 @@ clientDriverEnv.Library(
         'dbclient_connection.cpp',
         'dbclient_rs.cpp',
         'global_conn_pool.cpp',
+        env.Idlc('global_conn_pool.idl')[0],
         'replica_set_monitor.cpp',
         'replica_set_monitor_manager.cpp',
     ],
diff --git a/src/mongo/client/global_conn_pool.cpp b/src/mongo/client/global_conn_pool.cpp
index 2061c0c8f58..92f7bca11d4 100644
--- a/src/mongo/client/global_conn_pool.cpp
+++ b/src/mongo/client/global_conn_pool.cpp
@@ -33,33 +33,13 @@
 #include "mongo/client/global_conn_pool.h"
 
 #include "mongo/base/init.h"
-#include "mongo/db/server_parameters.h"
+#include "mongo/client/global_conn_pool_gen.h"
 
 namespace mongo {
 namespace {
 
-// Maximum connections per host the connection pool should store
-int maxConnsPerHost(200);
-ExportedServerParameter<int, ServerParameterType::kStartupOnly>  //
-    maxConnsPerHostParameter(ServerParameterSet::getGlobal(),
-                             "connPoolMaxConnsPerHost",
-                             &maxConnsPerHost);
-
-// Maximum in-use connections per host in the global connection pool
-int maxInUseConnsPerHost(std::numeric_limits<int>::max());
-ExportedServerParameter<int, ServerParameterType::kStartupOnly>  //
-    maxInUseConnsPerHostParameter(ServerParameterSet::getGlobal(),
-                                  "connPoolMaxInUseConnsPerHost",
-                                  &maxInUseConnsPerHost);
-
-// Amount of time, in minutes, to keep idle connections in the global connection pool
-int globalConnPoolIdleTimeout(std::numeric_limits<int>::max());
-ExportedServerParameter<int, ServerParameterType::kStartupOnly>  //
-    globalConnPoolIdleTimeoutParameter(ServerParameterSet::getGlobal(),
-                                       "globalConnPoolIdleTimeoutMinutes",
-                                       &globalConnPoolIdleTimeout);
-
-MONGO_INITIALIZER(InitializeGlobalConnectionPool)(InitializerContext* context) {
+MONGO_INITIALIZER_WITH_PREREQUISITES(InitializeGlobalConnectionPool, ("EndStartupOptionStorage"))
+(InitializerContext* context) {
     globalConnPool.setName("connection pool");
     globalConnPool.setMaxPoolSize(maxConnsPerHost);
     globalConnPool.setMaxInUse(maxInUseConnsPerHost);
diff --git a/src/mongo/client/global_conn_pool.idl b/src/mongo/client/global_conn_pool.idl
new file mode 100644
index 00000000000..a0415314159
--- /dev/null
+++ b/src/mongo/client/global_conn_pool.idl
@@ -0,0 +1,97 @@
+#    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.
+#
+
+global:
+  cpp_namespace: "mongo"
+
+imports:
+  - "mongo/idl/basic_types.idl"
+
+server_parameters:
+  connPoolMaxConnsPerHost:
+    description: >
+      New in version 2.6.
+
+      Available for both mongod and mongos.
+
+      Sets the maximum size of the legacy connection pools for
+      outgoing connections to other mongod instances in the global
+      connection pool. The size of a pool does not prevent the
+      creation of additional connections, but does prevent a
+      connection pool from retaining connections in excess of the
+      value of connPoolMaxConnsPerHost.
+
+      Only adjust this setting if your driver does not pool
+      connections and you're using authentication in the context of a
+      sharded cluster.
+
+    set_at:
+      - startup
+
+    cpp_vartype: int
+    cpp_varname: maxConnsPerHost
+    default: 200
+
+  connPoolMaxInUseConnsPerHost:
+    description: >
+      New in version 3.6.3.
+
+      Available for both mongod and mongos.
+
+      Sets the maximum number of in-use connections at any given time
+      for for outgoing connections to other mongod instances in the
+      legacy global connection pool.
+
+      By default, the parameter is unset.
+
+    set_at:
+      - startup
+
+    cpp_vartype: int
+    cpp_varname: maxInUseConnsPerHost
+    default:
+      expr: std::numeric_limits<int>::max()
+
+  globalConnPoolIdleTimeoutMinutes:
+    description: >
+      New in version 3.6.3.
+
+      Available for both mongod and mongos.
+
+      Sets the time limit that connection in the legacy global
+      connection pool can remain idle before being closed.
+
+      By default, the parameter is unset.
+
+    set_at:
+      - startup
+
+    cpp_vartype: int
+    cpp_varname: globalConnPoolIdleTimeout
+    default:
+      expr: std::numeric_limits<int>::max()