From 9dcb33e8f417d6b631c1607d991f4339ad213e88 Mon Sep 17 00:00:00 2001
From: Michael Friedrich <michael.friedrich@netways.de>
Date: Wed, 30 Sep 2015 16:58:18 +0200
Subject: [PATCH] Change object version to timestamps for diff updates on
 config sync

fixes #10257
---
 lib/base/configobject.cpp             | 9 ++-------
 lib/base/configobject.ti              | 2 +-
 lib/remote/apilistener-configsync.cpp | 9 +++++++++
 lib/remote/configobjectutility.cpp    | 3 +++
 4 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/lib/base/configobject.cpp b/lib/base/configobject.cpp
index 6ce9dfcb1..2c3a4ea18 100644
--- a/lib/base/configobject.cpp
+++ b/lib/base/configobject.cpp
@@ -223,7 +223,7 @@ void ConfigObject::ModifyAttribute(const String& attr, const Value& value, bool
 	SetField(fid, newValue);
 
 	if (updateVersion)
-		SetVersion(GetVersion() + 1);
+		SetVersion(Utility::GetTime());
 
 	if (updated_original_attributes)
 		NotifyOriginalAttributes();
@@ -341,11 +341,7 @@ void ConfigObject::RestoreAttribute(const String& attr)
 	original_attributes->Remove(attr);
 	SetField(fid, newValue);
 
-	/* increment the version. although restoring would mean
-	 * decrementing the version, but we cannot notify other
-	 * cluster nodes without increment.
-	 */
-	SetVersion(GetVersion() + 1);
+	SetVersion(Utility::GetTime());
 }
 
 bool ConfigObject::IsAttributeModified(const String& attr) const
@@ -638,7 +634,6 @@ void ConfigObject::DumpModifiedAttributes(const boost::function<void(const Confi
 			ObjectLock olock(originalAttributes);
 			BOOST_FOREACH(const Dictionary::Pair& kv, originalAttributes) {
 				String key = kv.first;
-				// TODO-MA: vars.os
 
 				Type::Ptr type = object->GetReflectionType();
 
diff --git a/lib/base/configobject.ti b/lib/base/configobject.ti
index 1e4a3f83f..168e7c7c5 100644
--- a/lib/base/configobject.ti
+++ b/lib/base/configobject.ti
@@ -95,7 +95,7 @@ abstract class ConfigObject : ConfigObjectBase
 	[protected] bool state_loaded;
 	Dictionary::Ptr original_attributes;
 	[state] int version {
-		default {{{ return 1; }}}
+		default {{{ return 0; }}}
 	};
 };
 
diff --git a/lib/remote/apilistener-configsync.cpp b/lib/remote/apilistener-configsync.cpp
index e4ebccc9f..aa671f655 100644
--- a/lib/remote/apilistener-configsync.cpp
+++ b/lib/remote/apilistener-configsync.cpp
@@ -392,6 +392,15 @@ void ApiListener::SendRuntimeConfigObjects(const JsonRpcConnection::Ptr& aclient
 			if (objZone.IsEmpty())
 				continue;
 
+			/* don't sync objects with an older version time than the endpoint's log position */
+			if (object->GetVersion() < endpoint->GetLocalLogPosition()) {
+				Log(LogDebug, "ApiListener")
+				    << "Skipping sync: object '" << object->GetName() << "'"
+				    << " is older than local log position of endpoint '"
+				    << endpoint->GetName() << "'.";
+				continue;
+			}
+
 			/* don't sync objects for non-matching parent-child zones */
 			if (!azone->IsChildOf(lzone) && azone != lzone) {
 				Log(LogDebug, "ApiListener")
diff --git a/lib/remote/configobjectutility.cpp b/lib/remote/configobjectutility.cpp
index eb62f8405..cd83d87bd 100644
--- a/lib/remote/configobjectutility.cpp
+++ b/lib/remote/configobjectutility.cpp
@@ -74,6 +74,9 @@ String ConfigObjectUtility::CreateObjectConfig(const Type::Ptr& type, const Stri
 
 	allAttrs->Remove("name");
 
+	/* update the version for config sync */
+	allAttrs->Set("version", Utility::GetTime());
+
 	std::ostringstream config;
 	ConfigWriter::EmitConfigItem(config, type->GetName(), name, false, templates, allAttrs);
 	ConfigWriter::EmitRaw(config, "\n");