SERVER-41794 Only log about sslMode being deprecated when it's set for the first time

Author: jbreams

src/mongo/idl/server_parameter.cpp

@@ -103,20 +103,26 @@ IDLServerParameterDeprecatedAlias::IDLServerParameterDeprecatedAlias(StringData
 void IDLServerParameterDeprecatedAlias::append(OperationContext* opCtx,
                                                BSONObjBuilder& b,
                                                const std::string& fieldName) {
-    warning() << "Use of deprecated server parameter '" << name() << "', please use '"
-              << _sp->name() << "' instead.";
+    std::call_once(_warnOnce, [&] {
+        warning() << "Use of deprecated server parameter '" << name() << "', please use '"
+                  << _sp->name() << "' instead.";
+    });
     _sp->append(opCtx, b, fieldName);
 }
 
 Status IDLServerParameterDeprecatedAlias::set(const BSONElement& newValueElement) {
-    warning() << "Use of deprecared server parameter '" << name() << "', please use '"
-              << _sp->name() << "' instead.";
+    std::call_once(_warnOnce, [&] {
+        warning() << "Use of deprecated server parameter '" << name() << "', please use '"
+                  << _sp->name() << "' instead.";
+    });
     return _sp->set(newValueElement);
 }
 
 Status IDLServerParameterDeprecatedAlias::setFromString(const std::string& str) {
-    warning() << "Use of deprecared server parameter '" << name() << "', please use '"
-              << _sp->name() << "' instead.";
+    std::call_once(_warnOnce, [&] {
+        warning() << "Use of deprecated server parameter '" << name() << "', please use '"
+                  << _sp->name() << "' instead.";
+    });
     return _sp->setFromString(str);
 }
 

src/mongo/idl/server_parameter.h

@@ -168,6 +168,7 @@ class IDLServerParameterDeprecatedAlias : public ServerParameter {
     Status setFromString(const std::string& str) final;
 
 private:
+    std::once_flag _warnOnce;
     ServerParameter* _sp;
 };
 

src/mongo/util/net/ssl_parameters.cpp

@@ -103,12 +103,17 @@ StatusWith<SSLParams::SSLModes> checkTLSModeTransition(T modeToString,
     }
 }
 
+std::once_flag warnForSSLMode;
+
 }  // namespace
 
 void SSLModeServerParameter::append(OperationContext*,
                                     BSONObjBuilder& builder,
                                     const std::string& fieldName) {
-    warning() << "Use of deprecared server parameter 'sslMode', please use 'tlsMode' instead.";
+    std::call_once(warnForSSLMode, [] {
+        warning() << "Use of deprecated server parameter 'sslMode', please use 'tlsMode' instead.";
+    });
+
     builder.append(fieldName, SSLParams::sslModeFormat(sslGlobalParams.sslMode.load()));
 }
 
@@ -121,7 +126,9 @@ void TLSModeServerParameter::append(OperationContext*,
 }
 
 Status SSLModeServerParameter::setFromString(const std::string& strMode) {
-    warning() << "Use of deprecared server parameter 'sslMode', please use 'tlsMode' instead.";
+    std::call_once(warnForSSLMode, [] {
+        warning() << "Use of deprecated server parameter 'sslMode', please use 'tlsMode' instead.";
+    });
 
     auto swNewMode = checkTLSModeTransition(
         SSLParams::sslModeFormat, SSLParams::sslModeParse, "sslMode", strMode);