SERVER-38955 Convert AuthManager and FCV setParameters to IDL

4 files changed, 100 insertions, 71 deletions

diff --git a/src/mongo/db/commands/SConscript b/src/mongo/db/commands/SConscript
index 35808b12da5..21d9929984a 100644
--- a/src/mongo/db/commands/SConscript
+++ b/src/mongo/db/commands/SConscript
@@ -188,6 +188,7 @@ env.Library(
     target="mongod_fcv",
     source=[
         "feature_compatibility_version.cpp",
+        env.Idlc('feature_compatibility_version.idl')[0],
     ],
     LIBDEPS=[
         'feature_compatibility_parsers',
@@ -196,6 +197,7 @@ env.Library(
         '$BUILD_DIR/mongo/db/commands',
         '$BUILD_DIR/mongo/db/dbdirectclient',
         '$BUILD_DIR/mongo/db/kill_sessions_local',
+        '$BUILD_DIR/mongo/idl/server_parameter',
         '$BUILD_DIR/mongo/executor/egress_tag_closer_manager',
     ],
 )
diff --git a/src/mongo/db/commands/feature_compatibility_version.cpp b/src/mongo/db/commands/feature_compatibility_version.cpp
index 0e2cc66572e..db37ae4819b 100644
--- a/src/mongo/db/commands/feature_compatibility_version.cpp
+++ b/src/mongo/db/commands/feature_compatibility_version.cpp
@@ -37,6 +37,7 @@
 #include "mongo/base/status.h"
 #include "mongo/db/catalog_raii.h"
 #include "mongo/db/commands/feature_compatibility_version_documentation.h"
+#include "mongo/db/commands/feature_compatibility_version_gen.h"
 #include "mongo/db/commands/feature_compatibility_version_parser.h"
 #include "mongo/db/dbdirectclient.h"
 #include "mongo/db/kill_sessions_local.h"
@@ -256,73 +257,58 @@ void FeatureCompatibilityVersion::_runUpdateCommand(OperationContext* opCtx,
 /**
  * Read-only server parameter for featureCompatibilityVersion.
  */
-class FeatureCompatibilityVersionParameter : public ServerParameter {
-public:
-    FeatureCompatibilityVersionParameter()
-        : ServerParameter(ServerParameterSet::getGlobal(),
-                          FeatureCompatibilityVersionParser::kParameterName.toString(),
-                          false,  // allowedToChangeAtStartup
-                          false   // allowedToChangeAtRuntime
-                          ) {}
-
-    virtual void append(OperationContext* opCtx, BSONObjBuilder& b, const std::string& name) {
-        BSONObjBuilder featureCompatibilityVersionBuilder(b.subobjStart(name));
-        uassert(ErrorCodes::UnknownFeatureCompatibilityVersion,
-                str::stream() << FeatureCompatibilityVersionParser::kParameterName
-                              << " is not yet known.",
-                serverGlobalParams.featureCompatibility.isVersionInitialized());
-        switch (serverGlobalParams.featureCompatibility.getVersion()) {
-            case ServerGlobalParams::FeatureCompatibility::Version::kFullyUpgradedTo42:
-                featureCompatibilityVersionBuilder.append(
-                    FeatureCompatibilityVersionParser::kVersionField,
-                    FeatureCompatibilityVersionParser::kVersion42);
-                return;
-            case ServerGlobalParams::FeatureCompatibility::Version::kUpgradingTo42:
-                featureCompatibilityVersionBuilder.append(
-                    FeatureCompatibilityVersionParser::kVersionField,
-                    FeatureCompatibilityVersionParser::kVersion40);
-                featureCompatibilityVersionBuilder.append(
-                    FeatureCompatibilityVersionParser::kTargetVersionField,
-                    FeatureCompatibilityVersionParser::kVersion42);
-                return;
-            case ServerGlobalParams::FeatureCompatibility::Version::kDowngradingTo40:
-                featureCompatibilityVersionBuilder.append(
-                    FeatureCompatibilityVersionParser::kVersionField,
-                    FeatureCompatibilityVersionParser::kVersion40);
-                featureCompatibilityVersionBuilder.append(
-                    FeatureCompatibilityVersionParser::kTargetVersionField,
-                    FeatureCompatibilityVersionParser::kVersion40);
-                return;
-            case ServerGlobalParams::FeatureCompatibility::Version::kFullyDowngradedTo40:
-                featureCompatibilityVersionBuilder.append(
-                    FeatureCompatibilityVersionParser::kVersionField,
-                    FeatureCompatibilityVersionParser::kVersion40);
-                return;
-            case ServerGlobalParams::FeatureCompatibility::Version::kUnsetDefault40Behavior:
-                // getVersion() does not return this value.
-                MONGO_UNREACHABLE;
-        }
-    }
-
-    virtual Status set(const BSONElement& newValueElement) {
-        return Status(ErrorCodes::IllegalOperation,
-                      str::stream()
-                          << FeatureCompatibilityVersionParser::kParameterName
-                          << " cannot be set via setParameter. See "
-                          << feature_compatibility_version_documentation::kCompatibilityLink
-                          << ".");
+// No ability to specify 'none' as set_at type,
+// so use 'startup' in the IDL file, then override to none here.
+FeatureCompatibilityVersionParameter::FeatureCompatibilityVersionParameter(StringData name,
+                                                                           ServerParameterType)
+    : ServerParameter(ServerParameterSet::getGlobal(), name, false, false) {}
+
+void FeatureCompatibilityVersionParameter::append(OperationContext* opCtx,
+                                                  BSONObjBuilder& b,
+                                                  const std::string& name) {
+    uassert(ErrorCodes::UnknownFeatureCompatibilityVersion,
+            str::stream() << name << " is not yet known.",
+            serverGlobalParams.featureCompatibility.isVersionInitialized());
+
+    BSONObjBuilder featureCompatibilityVersionBuilder(b.subobjStart(name));
+    switch (serverGlobalParams.featureCompatibility.getVersion()) {
+        case ServerGlobalParams::FeatureCompatibility::Version::kFullyUpgradedTo42:
+            featureCompatibilityVersionBuilder.append(
+                FeatureCompatibilityVersionParser::kVersionField,
+                FeatureCompatibilityVersionParser::kVersion42);
+            return;
+        case ServerGlobalParams::FeatureCompatibility::Version::kUpgradingTo42:
+            featureCompatibilityVersionBuilder.append(
+                FeatureCompatibilityVersionParser::kVersionField,
+                FeatureCompatibilityVersionParser::kVersion40);
+            featureCompatibilityVersionBuilder.append(
+                FeatureCompatibilityVersionParser::kTargetVersionField,
+                FeatureCompatibilityVersionParser::kVersion42);
+            return;
+        case ServerGlobalParams::FeatureCompatibility::Version::kDowngradingTo40:
+            featureCompatibilityVersionBuilder.append(
+                FeatureCompatibilityVersionParser::kVersionField,
+                FeatureCompatibilityVersionParser::kVersion40);
+            featureCompatibilityVersionBuilder.append(
+                FeatureCompatibilityVersionParser::kTargetVersionField,
+                FeatureCompatibilityVersionParser::kVersion40);
+            return;
+        case ServerGlobalParams::FeatureCompatibility::Version::kFullyDowngradedTo40:
+            featureCompatibilityVersionBuilder.append(
+                FeatureCompatibilityVersionParser::kVersionField,
+                FeatureCompatibilityVersionParser::kVersion40);
+            return;
+        case ServerGlobalParams::FeatureCompatibility::Version::kUnsetDefault40Behavior:
+            // getVersion() does not return this value.
+            MONGO_UNREACHABLE;
     }
+}
 
-    virtual Status setFromString(const std::string& str) {
-        return Status(ErrorCodes::IllegalOperation,
-                      str::stream()
-                          << FeatureCompatibilityVersionParser::kParameterName
-                          << " cannot be set via setParameter. See "
+Status FeatureCompatibilityVersionParameter::setFromString(const std::string&) {
+    return {ErrorCodes::IllegalOperation,
+            str::stream() << name() << " cannot be set via setParameter. See "
                           << feature_compatibility_version_documentation::kCompatibilityLink
-                          << ".");
-    }
-} featureCompatibilityVersionParameter;
-
-MONGO_EXPORT_STARTUP_SERVER_PARAMETER(internalValidateFeaturesAsMaster, bool, true);
+                          << "."};
+}
 
 }  // namespace mongo
diff --git a/src/mongo/db/commands/feature_compatibility_version.h b/src/mongo/db/commands/feature_compatibility_version.h
index 77ff5a3b9fc..9c2871e9ef9 100644
--- a/src/mongo/db/commands/feature_compatibility_version.h
+++ b/src/mongo/db/commands/feature_compatibility_version.h
@@ -41,12 +41,6 @@ namespace mongo {
 class BSONObj;
 class OperationContext;
 
-/**
- * Startup parameter to ignore featureCompatibilityVersion checks. This parameter cannot be set if
- * the node is started with --replSet. This should never be set by end users.
- */
-extern bool internalValidateFeaturesAsMaster;
-
 class FeatureCompatibilityVersion {
 public:
     /**
diff --git a/src/mongo/db/commands/feature_compatibility_version.idl b/src/mongo/db/commands/feature_compatibility_version.idl
new file mode 100644
index 00000000000..ca4ff5652a9
--- /dev/null
+++ b/src/mongo/db/commands/feature_compatibility_version.idl
@@ -0,0 +1,47 @@
+# 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"
+
+server_parameters:
+    featureCompatibilityVersion:
+        description: 'Read-only view of current Feature Compatability Version'
+        # Actually, never.
+        set_at: startup
+        cpp_class:
+            name: FeatureCompatibilityVersionParameter
+            override_ctor: true
+    internalValidateFeaturesAsMaster:
+        description: >
+            Startup parameter to ignore featureCompatibilityVersion checks. This parameter cannot be set if
+            the node is started with --replSet. This should never be set by end users.
+        set_at: startup
+        cpp_vartype: bool
+        cpp_varname: gInternalValidateFeaturesAsMaster
+        default: true