ConfigObjectUtility#CreateObject(): Use Defer for config path cle…

…anup

lib/remote/configobjectutility.cpp

@@ -7,6 +7,7 @@
 #include "config/configitem.hpp"
 #include "base/atomic-file.hpp"
 #include "base/configwriter.hpp"
+#include "base/defer.hpp"
 #include "base/exception.hpp"
 #include "base/dependencygraph.hpp"
 #include "base/tlsutility.hpp"
@@ -197,6 +198,12 @@ bool ConfigObjectUtility::CreateObject(const Type::Ptr& type, const String& full
 
 	AtomicFile::Write(path, 0644, config);
 
+	// Remove the just created config file in all the error cases and if the object creation
+	// succeeds the deferred callback will be cancelled.
+	Defer removeConfigPath([&path]{
+		Utility::Remove(path);
+	});
+
 	std::unique_ptr<Expression> expr = ConfigCompiler::CompileFile(path, String(), "_api");
 
 	try {
@@ -220,8 +227,6 @@ bool ConfigObjectUtility::CreateObject(const Type::Ptr& type, const String& full
 				Log(LogNotice, "ConfigObjectUtility")
 					<< "Failed to commit config item '" << fullName << "'. Aborting and removing config path '" << path << "'.";
 
-				Utility::Remove(path);
-
 				for (const boost::exception_ptr& ex : upq.GetExceptions()) {
 					errors->Add(DiagnosticInformation(ex, false));
 
@@ -243,8 +248,6 @@ bool ConfigObjectUtility::CreateObject(const Type::Ptr& type, const String& full
 				Log(LogNotice, "ConfigObjectUtility")
 					<< "Failed to activate config object '" << fullName << "'. Aborting and removing config path '" << path << "'.";
 
-				Utility::Remove(path);
-
 				for (const boost::exception_ptr& ex : upq.GetExceptions()) {
 					errors->Add(DiagnosticInformation(ex, false));
 
@@ -268,16 +271,16 @@ bool ConfigObjectUtility::CreateObject(const Type::Ptr& type, const String& full
 		ConfigObject::Ptr obj = ctype->GetObject(fullName);
 
 		if (obj) {
+			// Object is successfully created and activated, so don't remove its config.
+			removeConfigPath.Cancel();
+
 			Log(LogInformation, "ConfigObjectUtility")
 				<< "Created and activated object '" << fullName << "' of type '" << type->GetName() << "'.";
 		} else {
 			Log(LogNotice, "ConfigObjectUtility")
 				<< "Object '" << fullName << "' was not created but ignored due to errors.";
 		}
-
 	} catch (const std::exception& ex) {
-		Utility::Remove(path);
-
 		if (errors)
 			errors->Add(DiagnosticInformation(ex, false));