Remove 'property' vs 'variable' dichotomy in favour of 'meta objects' (to match serialisation).

git-svn-id: http://svn.drobilla.net/lad/trunk/ingen@2016 a436a847-0d15-0410-975c-d299462d15a1

19 files changed, 144 insertions, 230 deletions

diff --git a/src/engine/ClientBroadcaster.cpp b/src/engine/ClientBroadcaster.cpp
index c0f107de..8aaffe94 100644
--- a/src/engine/ClientBroadcaster.cpp
+++ b/src/engine/ClientBroadcaster.cpp
@@ -162,27 +162,15 @@ ClientBroadcaster::send_disconnection(const Path& src_port_path, const Path& dst
 }
 
 
-/** Send notification of a variable update.
- *
- * Like control changes, does not send update to client that set the variable, if applicable.
- */
-void
-ClientBroadcaster::send_variable_change(const URI& node_path, const URI& key, const Atom& value)
-{
-	for (Clients::const_iterator i = _clients.begin(); i != _clients.end(); ++i)
-		(*i).second->set_variable(node_path, key, value);
-}
-
-
 /** Send notification of a property update.
  *
  * Like control changes, does not send update to client that set the property, if applicable.
  */
 void
-ClientBroadcaster::send_property_change(const URI& node_path, const URI& key, const Atom& value)
+ClientBroadcaster::send_property_change(const URI& subject, const URI& key, const Atom& value)
 {
 	for (Clients::const_iterator i = _clients.begin(); i != _clients.end(); ++i)
-		(*i).second->set_property(node_path, key, value);
+		(*i).second->set_property(subject, key, value);
 }
 
 
diff --git a/src/engine/GraphObjectImpl.cpp b/src/engine/GraphObjectImpl.cpp
index ef4e2cd4..40cdc792 100644
--- a/src/engine/GraphObjectImpl.cpp
+++ b/src/engine/GraphObjectImpl.cpp
@@ -27,26 +27,38 @@ namespace Ingen {
 
 using namespace Shared;
 
+
+GraphObjectImpl::GraphObjectImpl(GraphObjectImpl* parent, const std::string& name, bool polyphonic)
+	: ResourceImpl((parent ? parent->path().base() : Raul::Path::root_uri) + name)
+	, _parent(parent)
+	, _name(name)
+	, _meta(std::string("meta:#") + path().chop_start("/"))
+	, _polyphonic(polyphonic)
+{
+	assert(parent == NULL || _name.length() > 0);
+	assert(_name.find("/") == std::string::npos);
+}
+
+
+void
+GraphObjectImpl::add_meta_property(const Raul::URI& key, const Atom& value)
+{
+	_meta.add_property(key, value);
+}
+
+
 void
-GraphObjectImpl::set_variable(const Raul::URI& key, const Atom& value)
+GraphObjectImpl::set_meta_property(const Raul::URI& key, const Atom& value)
 {
-	// Ignore duplicate statements
-	typedef Resource::Properties::const_iterator iterator;
-	const std::pair<iterator,iterator> range = _variables.equal_range(key);
-	for (iterator i = range.first; i != range.second; ++i)
-		if (i->second == value)
-			return;
-
-	_variables.insert(make_pair(key, value));
+	_meta.set_property(key, value);
 }
 
 
 const Atom&
-GraphObjectImpl::get_variable(const Raul::URI& key)
+GraphObjectImpl::get_property(const Raul::URI& key) const
 {
-	static const Atom null_atom;
-	Properties::iterator i = _variables.find(key);
-	return (i != _variables.end()) ? (*i).second : null_atom;
+	Resource::Properties::const_iterator i = properties().find(key);
+	return (i != properties().end()) ? i->second : _meta.get_property(key);
 }
 
 
diff --git a/src/engine/GraphObjectImpl.hpp b/src/engine/GraphObjectImpl.hpp
index a6f6b532..c8b0c13c 100644
--- a/src/engine/GraphObjectImpl.hpp
+++ b/src/engine/GraphObjectImpl.hpp
@@ -49,15 +49,17 @@ class GraphObjectImpl : virtual public Ingen::Shared::GraphObject
 public:
 	virtual ~GraphObjectImpl() {}
 
+	const Raul::URI    meta_uri() const { return _meta.uri(); }
+	const Raul::URI    uri()      const { return path(); }
+	const Raul::Symbol symbol()   const { return _name; }
+
 	bool         polyphonic() const                       { return _polyphonic; }
 	virtual bool set_polyphonic(Raul::Maid& maid, bool p) { _polyphonic = p; return true; }
 
-	GraphObject* graph_parent() const { return _parent; }
-
-	const Raul::URI uri() const { return path(); }
-
-	inline GraphObjectImpl* parent() const { return _parent; }
-	const Raul::Symbol      symbol() const { return _name; }
+	GraphObject*     graph_parent() const { return _parent; }
+	GraphObjectImpl* parent()       const { return _parent; }
+	Resource&        meta()               { return _meta; }
+	const Resource&  meta()         const { return _meta; }
 
 	virtual void process(ProcessContext& context) = 0;
 
@@ -68,18 +70,16 @@ public:
 		assert(_name.find("/") == std::string::npos);
 	}
 
-	const Raul::Atom& get_variable(const Raul::URI& key);
-	void              set_variable(const Raul::URI& key, const Raul::Atom& value);
-
-	const Properties&  variables()  const { return _variables; }
-	Properties&        variables()        { return _variables; }
+	const Raul::Atom& get_property(const Raul::URI& key) const;
+	void              add_meta_property(const Raul::URI& key, const Raul::Atom& value);
+	void              set_meta_property(const Raul::URI& key, const Raul::Atom& value);
 
 	/** The Patch this object is a child of. */
 	virtual PatchImpl* parent_patch() const;
 
 	/** Raul::Path is dynamically generated from parent to ease renaming */
 	const Raul::Path path() const {
-		if (_parent == NULL)
+		if (!_parent)
 			return Raul::Path(std::string("/").append(_name));
 		else if (_parent->path().is_root())
 			return Raul::Path(std::string("/").append(_name));
@@ -90,22 +90,12 @@ public:
 	SharedPtr<GraphObject> find_child(const std::string& name) const;
 
 protected:
-	GraphObjectImpl(GraphObjectImpl* parent, const std::string& name, bool polyphonic=false)
-		: ResourceImpl((parent ? parent->path().base() : Raul::Path::root_uri) + name)
-		, _parent(parent)
-		, _name(name)
-		, _polyphonic(polyphonic)
-	{
-		assert(parent == NULL || _name.length() > 0);
-		assert(_name.find("/") == std::string::npos);
-	}
+	GraphObjectImpl(GraphObjectImpl* parent, const std::string& name, bool polyphonic=false);
 
 	GraphObjectImpl* _parent;
 	std::string      _name;
+	ResourceImpl     _meta;
 	bool             _polyphonic;
-
-private:
-	Properties _variables;
 };
 
 
diff --git a/src/engine/HTTPClientSender.cpp b/src/engine/HTTPClientSender.cpp
index 83d3f1b2..fa6421b9 100644
--- a/src/engine/HTTPClientSender.cpp
+++ b/src/engine/HTTPClientSender.cpp
@@ -50,7 +50,7 @@ HTTPClientSender::error(const std::string& msg)
 
 
 void
-HTTPClientSender::put(const Path&                         path,
+HTTPClientSender::put(const URI&                          path,
                       const Shared::Resource::Properties& properties)
 {
 	cerr << "HTTP CLIENT PUT " << path << endl;
@@ -75,7 +75,7 @@ HTTPClientSender::clear_patch(const Path& patch_path)
 void
 HTTPClientSender::connect(const Path& src_path, const Path& dst_path)
 {
-	string msg = string(
+	const string msg = string(
 			"@prefix rdf:       <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .\n"
 			"@prefix ingen:     <http://drobilla.net/ns/ingen#> .\n"
 			"@prefix lv2var:    <http://lv2plug.in/ns/ext/instance-var#> .\n\n<").append(
@@ -94,30 +94,15 @@ HTTPClientSender::disconnect(const Path& src_path, const Path& dst_path)
 
 
 void
-HTTPClientSender::set_variable(const URI& path, const URI& key, const Atom& value)
+HTTPClientSender::set_property(const URI& subject, const URI& key, const Atom& value)
 {
 	Redland::Node node = AtomRDF::atom_to_node(*_engine.world()->rdf_world, value);
-	string msg = string(
-			"@prefix rdf:       <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .\n"
-			"@prefix ingenuity: <http://drobilla.net/ns/ingenuity#> .\n"
-			"@prefix lv2var:    <http://lv2plug.in/ns/ext/instance-var#> .\n\n<").append(
-			path.str()).append("> lv2var:variable [\n"
-			"rdf:predicate ").append(key.str()).append(" ;\n"
-			"rdf:value     ").append(node.to_string()).append("\n] .\n");
-	send_chunk(msg);
-}
-
-
-void
-HTTPClientSender::set_property(const URI& path, const URI& key, const Atom& value)
-{
-	Redland::Node node = AtomRDF::atom_to_node(*_engine.world()->rdf_world, value);
-	string msg = string(
+	const string msg = string(
 			"@prefix rdf:       <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .\n"
 			"@prefix ingen:     <http://drobilla.net/ns/ingen#> .\n"
 			"@prefix ingenuity: <http://drobilla.net/ns/ingenuity#> .\n"
 			"@prefix lv2var:    <http://lv2plug.in/ns/ext/instance-var#> .\n\n<").append(
-			path.str()).append("> ingen:property [\n"
+			subject.str()).append("> ingen:property [\n"
 			"rdf:predicate ").append(key.str()).append(" ;\n"
 			"rdf:value     ").append(node.to_string()).append("\n] .\n");
 	send_chunk(msg);
@@ -128,7 +113,7 @@ void
 HTTPClientSender::set_port_value(const Path& port_path, const Atom& value)
 {
 	Redland::Node node = AtomRDF::atom_to_node(*_engine.world()->rdf_world, value);
-	string msg = string(
+	const string msg = string(
 			"@prefix ingen: <http://drobilla.net/ns/ingen#> .\n\n<").append(
 			port_path.str()).append("> ingen:value ").append(node.to_string()).append(" .\n");
 	send_chunk(msg);
@@ -148,7 +133,7 @@ HTTPClientSender::set_voice_value(const Path& port_path, uint32_t voice, const A
 void
 HTTPClientSender::activity(const Path& path)
 {
-	string msg = string(
+	const string msg = string(
 			"@prefix ingen: <http://drobilla.net/ns/ingen#> .\n\n<").append(
 			path.str()).append("> ingen:activity true .\n");
 	send_chunk(msg);
diff --git a/src/engine/HTTPClientSender.hpp b/src/engine/HTTPClientSender.hpp
index fb045194..9a7948ff 100644
--- a/src/engine/HTTPClientSender.hpp
+++ b/src/engine/HTTPClientSender.hpp
@@ -78,7 +78,7 @@ public:
 	                        const Raul::URI&    type_uri,
 	                        const Raul::Symbol& symbol);
 
-	virtual void put(const Raul::Path&                   path,
+	virtual void put(const Raul::URI&                    path,
 	                 const Shared::Resource::Properties& properties);
 
 	virtual void clear_patch(const Raul::Path& path);
@@ -94,10 +94,6 @@ public:
 	virtual void disconnect(const Raul::Path& src_port_path,
 	                        const Raul::Path& dst_port_path);
 
-	virtual void set_variable(const Raul::URI&  subject_path,
-	                          const Raul::URI&  predicate,
-	                          const Raul::Atom& value);
-
 	virtual void set_property(const Raul::URI&  subject_path,
 	                          const Raul::URI&  predicate,
 	                          const Raul::Atom& value);
diff --git a/src/engine/LADSPANode.cpp b/src/engine/LADSPANode.cpp
index 4431065a..e761ff60 100644
--- a/src/engine/LADSPANode.cpp
+++ b/src/engine/LADSPANode.cpp
@@ -241,11 +241,11 @@ LADSPANode::instantiate()
 
 		if (port->is_input() && port->buffer_size() == 1) {
 			if (min)
-				port->set_variable("lv2:minimum", min.get());
+				port->set_meta_property("lv2:minimum", min.get());
 			if (max)
-				port->set_variable("lv2:maximum", max.get());
+				port->set_meta_property("lv2:maximum", max.get());
 			if (default_val)
-				port->set_variable("lv2:default", default_val.get());
+				port->set_meta_property("lv2:default", default_val.get());
 		}
 	}
 
diff --git a/src/engine/OSCClientSender.cpp b/src/engine/OSCClientSender.cpp
index 594266aa..5a941dc2 100644
--- a/src/engine/OSCClientSender.cpp
+++ b/src/engine/OSCClientSender.cpp
@@ -105,7 +105,7 @@ OSCClientSender::error(const std::string& msg)
  * PUT a set of properties to a path (see \ref methods).
  */
 void
-OSCClientSender::put(const Raul::Path&                   path,
+OSCClientSender::put(const Raul::URI&                    path,
                      const Shared::Resource::Properties& properties)
 {
 	cerr << "OSC CLIENT PUT " << path << endl;
@@ -183,25 +183,6 @@ OSCClientSender::disconnect(const Path& src_port_path, const Path& dst_port_path
 
 
 /** \page client_osc_namespace
- * <h2>/ingen/set_variable</h2>
- * \arg \b path (string) - Path of the object associated with variable (node, patch, or port)
- * \arg \b key (string)
- * \arg \b value (string)
- * ,
- * Notification of a variable.
- */
-void
-OSCClientSender::set_variable(const URI& path, const URI& key, const Atom& value)
-{
-	lo_message m = lo_message_new();
-	lo_message_add_string(m, path.c_str());
-	lo_message_add_string(m, key.c_str());
-	AtomLiblo::lo_message_add_atom(m, value);
-	send_message("/ingen/set_variable", m);
-}
-
-
-/** \page client_osc_namespace
  * <h2>/ingen/set_property</h2>
  * \arg \b path (string) - Path of the object associated with property (node, patch, or port)
  * \arg \b key (string)
diff --git a/src/engine/OSCClientSender.hpp b/src/engine/OSCClientSender.hpp
index 4a0742eb..333fee49 100644
--- a/src/engine/OSCClientSender.hpp
+++ b/src/engine/OSCClientSender.hpp
@@ -75,7 +75,7 @@ public:
 	                        const Raul::URI&    type_uri,
 	                        const Raul::Symbol& symbol);
 
-	virtual void put(const Raul::Path&                   path,
+	virtual void put(const Raul::URI&                    path,
 	                 const Shared::Resource::Properties& properties);
 
 	virtual void clear_patch(const Raul::Path& path);
@@ -91,11 +91,7 @@ public:
 	virtual void disconnect(const Raul::Path& src_port_path,
 	                        const Raul::Path& dst_port_path);
 
-	virtual void set_variable(const Raul::URI&  subject_path,
-	                          const Raul::URI&  predicate,
-	                          const Raul::Atom& value);
-
-	virtual void set_property(const Raul::URI&  subject_path,
+	virtual void set_property(const Raul::URI&  subject,
 	                          const Raul::URI&  predicate,
 	                          const Raul::Atom& value);
 
diff --git a/src/engine/OSCEngineReceiver.cpp b/src/engine/OSCEngineReceiver.cpp
index 21a9b898..6cdc4ea2 100644
--- a/src/engine/OSCEngineReceiver.cpp
+++ b/src/engine/OSCEngineReceiver.cpp
@@ -641,31 +641,6 @@ OSCEngineReceiver::_midi_learn_cb(const char* path, const char* types, lo_arg**
 
 
 /** \page engine_osc_namespace
- * <h2>/ingen/set_variable</h2>
- * \arg \b response-id (integer)
- * \arg \b object-path (string) - Full path of object to associate variable with
- * \arg \b key (string) - Key (index/predicate/ID) for new variable
- * \arg \b value (string) - Value of new variable
- *
- * Set a variable, associated with a graph object.
- */
-int
-OSCEngineReceiver::_variable_set_cb(const char* path, const char* types, lo_arg** argv, int argc, lo_message msg)
-{
-	if (argc != 4 || types[0] != 'i' || types[1] != 's' || types[2] != 's')
-		return 1;
-
-	const char* object_path = &argv[1]->s;
-	const char* key         = &argv[2]->s;
-
-	Raul::Atom value = Raul::AtomLiblo::lo_arg_to_atom(types[3], argv[3]);
-
-	set_variable(object_path, key, value);
-	return 0;
-}
-
-
-/** \page engine_osc_namespace
  * <h2>/ingen/set_property</h2>
  * \arg \b response-id (integer)
  * \arg \b object-path (string) - Full path of object to associate variable with
diff --git a/src/engine/ObjectSender.cpp b/src/engine/ObjectSender.cpp
index 9bf70cbf..072d6c52 100644
--- a/src/engine/ObjectSender.cpp
+++ b/src/engine/ObjectSender.cpp
@@ -62,14 +62,10 @@ ObjectSender::send_patch(ClientInterface* client, const PatchImpl* patch, bool r
 	if (bundle)
 		client->transfer_begin();
 
-	client->put(patch->path(), patch->properties());
+	client->put(patch->meta_uri(), patch->meta().properties());
+	client->put(patch->path(),     patch->properties());
 
 	if (recursive) {
-		// Send variables
-		const GraphObjectImpl::Properties& data = patch->variables();
-		for (GraphObjectImpl::Properties::const_iterator j = data.begin(); j != data.end(); ++j)
-			client->set_variable(patch->path(), (*j).first, (*j).second);
-
 		// Send nodes
 		for (List<NodeImpl*>::const_iterator j = patch->nodes().begin();
 				j != patch->nodes().end(); ++j) {
@@ -113,12 +109,7 @@ ObjectSender::send_node(ClientInterface* client, const NodeImpl* node, bool recu
 	if (bundle)
 		client->transfer_begin();
 
-	client->put(node->path(), node->variables());
-
-	// Send variables
-	const GraphObjectImpl::Properties& prop = node->variables();
-	for (GraphObjectImpl::Properties::const_iterator j = prop.begin(); j != prop.end(); ++j)
-		client->set_variable(node->path(), (*j).first, (*j).second);
+	client->put(node->path(), node->properties());
 
 	if (recursive) {
 		// Send ports
@@ -139,26 +130,19 @@ ObjectSender::send_port(ClientInterface* client, const PortImpl* port, bool bund
 	if (bundle)
 		client->bundle_begin();
 
-	client->put(port->path(), port->properties());
-
 	PatchImpl* graph_parent = dynamic_cast<PatchImpl*>(port->parent_node());
-	if (graph_parent && graph_parent->internal_polyphony() > 1)
-		client->set_variable(port->path(), "ingen:polyphonic", bool(port->polyphonic()));
 
-	// Send variables
-	const GraphObjectImpl::Properties& data = port->variables();
-	for (GraphObjectImpl::Properties::const_iterator j = data.begin(); j != data.end(); ++j)
-		client->set_variable(port->path(), (*j).first, (*j).second);
+	if (graph_parent)
+		client->put(port->meta_uri(), port->meta().properties());
+
+	client->put(port->path(), port->properties());
 
-	// Send properties
-	const GraphObjectImpl::Properties& prop = port->properties();
-	for (GraphObjectImpl::Properties::const_iterator j = prop.begin(); j != prop.end(); ++j)
-		client->set_property(port->path(), (*j).first, (*j).second);
+	if (graph_parent && graph_parent->internal_polyphony() > 1)
+		client->set_property(port->meta_uri(), "ingen:polyphonic", bool(port->polyphonic()));
 
 	// Send control value
 	if (port->type() == DataType::CONTROL) {
-		const Sample value = dynamic_cast<const AudioBuffer*>(port->buffer(0))->value_at(0);
-		//cerr << port->path() << " sending default value " << default_value << endl;
+		const Sample& value = dynamic_cast<const AudioBuffer*>(port->buffer(0))->value_at(0);
 		client->set_port_value(port->path(), value);
 	}
 
diff --git a/src/engine/QueuedEngineInterface.cpp b/src/engine/QueuedEngineInterface.cpp
index 7c9c2c1a..4b2926e7 100644
--- a/src/engine/QueuedEngineInterface.cpp
+++ b/src/engine/QueuedEngineInterface.cpp
@@ -152,11 +152,15 @@ QueuedEngineInterface::bundle_end()
 
 
 void
-QueuedEngineInterface::put(const Path&                 path,
+QueuedEngineInterface::put(const URI&                  uri,
                            const Resource::Properties& properties)
 {
+	size_t hash = uri.find("#");
+	bool   meta = (hash != string::npos);
+	Path   path(meta ? (string("/") + uri.chop_start("#")) : uri.str());
+
 	typedef Resource::Properties::const_iterator iterator;
-	cerr << "ENGINE PUT " << path << " {" << endl;
+	cerr << "ENGINE PUT " << path << " (" << path << ") {" << endl;
 	for (iterator i = properties.begin(); i != properties.end(); ++i)
 		cerr << "\t" << i->first << " = " << i->second << " :: " << i->second.type() << endl;
 	cerr << "}" << endl;
@@ -255,20 +259,14 @@ QueuedEngineInterface::midi_learn(const Path& node_path)
 
 
 void
-QueuedEngineInterface::set_variable(const URI&  path,
-                                    const URI&  predicate,
-                                    const Atom& value)
-{
-	push_queued(new SetMetadataEvent(_engine, _responder, now(), false, path, predicate, value));
-}
-
-
-void
-QueuedEngineInterface::set_property(const URI&  path,
+QueuedEngineInterface::set_property(const URI&  uri,
                                     const URI&  predicate,
                                     const Atom& value)
 {
-	push_queued(new SetMetadataEvent(_engine, _responder, now(), true, path, predicate, value));
+	size_t hash = uri.find("#");
+	bool   meta = (hash != string::npos);
+	Path path = meta ? (string("/") + path.chop_start("/")) : uri.str();
+	push_queued(new SetMetadataEvent(_engine, _responder, now(), meta, path, predicate, value));
 }
 
 // Requests //
diff --git a/src/engine/QueuedEngineInterface.hpp b/src/engine/QueuedEngineInterface.hpp
index 2a94abff..43237ac8 100644
--- a/src/engine/QueuedEngineInterface.hpp
+++ b/src/engine/QueuedEngineInterface.hpp
@@ -71,7 +71,7 @@ public:
 
 	// CommonInterface object commands
 
-	virtual void put(const Raul::Path&                   path,
+	virtual void put(const Raul::URI&                    path,
 	                 const Shared::Resource::Properties& properties);
 
 	virtual void move(const Raul::Path& old_path,
@@ -83,10 +83,6 @@ public:
 	virtual void disconnect(const Raul::Path& src_port_path,
 	                        const Raul::Path& dst_port_path);
 
-	virtual void set_variable(const Raul::URI&  subject_path,
-	                          const Raul::URI&  predicate,
-	                          const Raul::Atom& value);
-
 	virtual void set_property(const Raul::URI&  subject_path,
 	                          const Raul::URI&  predicate,
 	                          const Raul::Atom& value);
diff --git a/src/engine/events/CreateNodeEvent.cpp b/src/engine/events/CreateNodeEvent.cpp
index 6f3ed834..718a94a3 100644
--- a/src/engine/events/CreateNodeEvent.cpp
+++ b/src/engine/events/CreateNodeEvent.cpp
@@ -89,7 +89,7 @@ CreateNodeEvent::pre_process()
 	if (_patch && plugin) {
 
 		_node = plugin->instantiate(_path.name(), _polyphonic, _patch, _engine);
-		_node->variables().insert(_properties.begin(), _properties.end());
+		_node->properties().insert(_properties.begin(), _properties.end());
 
 		if (_node != NULL) {
 			_node->activate();
diff --git a/src/engine/events/CreatePatchEvent.cpp b/src/engine/events/CreatePatchEvent.cpp
index f4a60760..16f749a3 100644
--- a/src/engine/events/CreatePatchEvent.cpp
+++ b/src/engine/events/CreatePatchEvent.cpp
@@ -83,7 +83,9 @@ CreatePatchEvent::pre_process()
 		poly = _poly;
 
 	_patch = new PatchImpl(_engine, path.name(), poly, _parent, _engine.audio_driver()->sample_rate(), _engine.audio_driver()->buffer_size(), _poly);
-	_patch->properties().insert(_properties.begin(), _properties.end());
+	_patch->meta().properties().insert(_properties.begin(), _properties.end());
+	_patch->set_property("rdf:type", Atom(Atom::URI, "ingen:Node"));
+	_patch->set_property("rdf:instanceOf", Atom(Atom::URI, _patch->meta_uri().str()));
 
 	if (_parent != NULL) {
 		_parent->add_node(new PatchImpl::Nodes::Node(_patch));
diff --git a/src/engine/events/CreatePortEvent.cpp b/src/engine/events/CreatePortEvent.cpp
index 38c3587c..e954c56d 100644
--- a/src/engine/events/CreatePortEvent.cpp
+++ b/src/engine/events/CreatePortEvent.cpp
@@ -15,10 +15,11 @@
  * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
-#include "raul/Path.hpp"
 #include "raul/Array.hpp"
+#include "raul/Atom.hpp"
 #include "raul/List.hpp"
 #include "raul/Maid.hpp"
+#include "raul/Path.hpp"
 #include "Responder.hpp"
 #include "CreatePortEvent.hpp"
 #include "PatchImpl.hpp"
@@ -35,6 +36,7 @@
 #include "DuplexPort.hpp"
 
 using namespace std;
+using namespace Raul;
 
 namespace Ingen {
 
@@ -96,7 +98,8 @@ CreatePortEvent::pre_process()
 		const uint32_t old_num_ports = _patch->num_ports();
 
 		_patch_port = _patch->create_port(_path.name(), _data_type, buffer_size, _is_output);
-		_patch_port->properties().insert(_properties.begin(), _properties.end());
+		_patch_port->set_property("rdf:instanceOf", Atom(Atom::URI, _patch_port->meta_uri().str()));
+		_patch_port->meta().properties().insert(_properties.begin(), _properties.end());
 
 		if (_patch_port) {
 
diff --git a/src/engine/events/RequestMetadataEvent.cpp b/src/engine/events/RequestMetadataEvent.cpp
index fe1f0cab..5d0b15bc 100644
--- a/src/engine/events/RequestMetadataEvent.cpp
+++ b/src/engine/events/RequestMetadataEvent.cpp
@@ -37,7 +37,7 @@ using namespace Shared;
 RequestMetadataEvent::RequestMetadataEvent(Engine&              engine,
 	                                       SharedPtr<Responder> responder,
 	                                       SampleCount          timestamp,
-	                                       bool                 is_property,
+	                                       bool                 is_meta,
 	                                       const URI&           subject,
 	                                       const URI&           key)
 	: QueuedEvent(engine, responder, timestamp)
@@ -46,7 +46,7 @@ RequestMetadataEvent::RequestMetadataEvent(Engine&              engine,
 	, _uri(subject)
 	, _key(key)
 	, _resource(0)
-	, _is_property(is_property)
+	, _is_meta(is_meta)
 {
 }
 
@@ -67,12 +67,17 @@ RequestMetadataEvent::pre_process()
 		}
 	}
 
-	if (_key.str() == "ingen:value")
-		_special_type = PORT_VALUE;
-	else if (!is_object || _is_property)
+	GraphObjectImpl* obj = dynamic_cast<GraphObjectImpl*>(_resource);
+	if (obj) {
+		if (_key.str() == "ingen:value")
+			_special_type = PORT_VALUE;
+		else if (_is_meta)
+			_value = obj->meta().get_property(_key);
+		else
+			_value = obj->get_property(_key);
+	} else {
 		_value = _resource->get_property(_key);
-	else
-		_value = dynamic_cast<GraphObjectImpl*>(_resource)->get_variable(_key);
+	}
 
 	QueuedEvent::pre_process();
 }
@@ -111,7 +116,7 @@ RequestMetadataEvent::post_process()
 			_responder->respond_error(msg);
 		} else {
 			_responder->respond_ok();
-			_responder->client()->set_variable(_uri, _key, _value);
+			_responder->client()->set_property(_uri, _key, _value);
 		}
 	} else {
 		_responder->respond_error("Unknown client");
diff --git a/src/engine/events/RequestMetadataEvent.hpp b/src/engine/events/RequestMetadataEvent.hpp
index 1445f83d..9d1c6bf0 100644
--- a/src/engine/events/RequestMetadataEvent.hpp
+++ b/src/engine/events/RequestMetadataEvent.hpp
@@ -39,7 +39,7 @@ public:
 	RequestMetadataEvent(Engine&              engine,
 	                     SharedPtr<Responder> responder,
 	                     SampleCount          timestamp,
-	                     bool                 property,
+	                     bool                 meta,
 	                     const Raul::URI&     path,
 	                     const Raul::URI&     key);
 
@@ -58,7 +58,7 @@ private:
 	Raul::URI             _key;
 	Raul::Atom            _value;
 	Shared::ResourceImpl* _resource;
-	bool                  _is_property;
+	bool                  _is_meta;
 };
 
 
diff --git a/src/engine/events/SetMetadataEvent.cpp b/src/engine/events/SetMetadataEvent.cpp
index af36b5d3..482656ca 100644
--- a/src/engine/events/SetMetadataEvent.cpp
+++ b/src/engine/events/SetMetadataEvent.cpp
@@ -37,20 +37,21 @@ SetMetadataEvent::SetMetadataEvent(
 		Engine&              engine,
 		SharedPtr<Responder> responder,
 		SampleCount          timestamp,
-		bool                 property,
+		bool                 meta,
 		const URI&           subject,
 		const URI&           key,
 		const Atom&          value)
 	: QueuedEvent(engine, responder, timestamp)
 	, _error(NO_ERROR)
 	, _special_type(NONE)
-	, _property(property)
 	, _subject(subject)
 	, _key(key)
 	, _value(value)
 	, _object(NULL)
 	, _patch(NULL)
 	, _compiled_patch(NULL)
+	, _is_meta(meta)
+	, _success(false)
 {
 }
 
@@ -70,40 +71,45 @@ SetMetadataEvent::pre_process()
 	}
 
 	/*cerr << "SET " << _object->path() << (_property ? " PROP " : " VAR ")
-		<<	_key << " :: " << _value.type() << endl;*/
+	  <<	_key << " :: " << _value.type() << endl;*/
 
-	if (_property || !dynamic_cast<GraphObjectImpl*>(_object))
-		_object->set_property(_key, _value);
-	else
-		dynamic_cast<GraphObjectImpl*>(_object)->set_variable(_key, _value);
-
-	_patch = dynamic_cast<PatchImpl*>(_object);
-
-	if (_key.str() == "ingen:broadcast") {
-		_special_type = ENABLE_BROADCAST;
-	} else if (_patch) {
-		if (!_property && _key.str() == "ingen:enabled") {
-			if (_value.type() == Atom::BOOL) {
-				_special_type = ENABLE;
-				if (_value.get_bool() && !_patch->compiled_patch())
-					_compiled_patch = _patch->compile();
-			} else {
-				_error = BAD_TYPE;
-			}
-		} else if (!_property && _key.str() == "ingen:polyphonic") {
-			if (_value.type() == Atom::BOOL) {
-				_special_type = POLYPHONIC;
-			} else {
-				_error = BAD_TYPE;
-			}
-		} else if (_property && _key.str() == "ingen:polyphony") {
-			if (_value.type() == Atom::INT) {
-				_special_type = POLYPHONY;
-				_patch->prepare_internal_poly(_value.get_int32());
-			} else {
-				_error = BAD_TYPE;
+	GraphObjectImpl* obj = dynamic_cast<GraphObjectImpl*>(_object);
+	if (obj) {
+		if (_is_meta)
+			obj->meta().set_property(_key, _value);
+		else
+			obj->set_property(_key, _value);
+
+		_patch = dynamic_cast<PatchImpl*>(_object);
+
+		if (_key.str() == "ingen:broadcast") {
+			_special_type = ENABLE_BROADCAST;
+		} else if (_patch) {
+			if (_key.str() == "ingen:enabled") {
+				if (_value.type() == Atom::BOOL) {
+					_special_type = ENABLE;
+					if (_value.get_bool() && !_patch->compiled_patch())
+						_compiled_patch = _patch->compile();
+				} else {
+					_error = BAD_TYPE;
+				}
+			} else if (_key.str() == "ingen:polyphonic") {
+				if (_value.type() == Atom::BOOL) {
+					_special_type = POLYPHONIC;
+				} else {
+					_error = BAD_TYPE;
+				}
+			} else if (_key.str() == "ingen:polyphony") {
+				if (_value.type() == Atom::INT) {
+					_special_type = POLYPHONY;
+					_patch->prepare_internal_poly(_value.get_int32());
+				} else {
+					_error = BAD_TYPE;
+				}
 			}
 		}
+	} else {
+		_object->set_property(_key, _value);
 	}
 
 	QueuedEvent::pre_process();
@@ -155,10 +161,7 @@ SetMetadataEvent::post_process()
 	switch (_error) {
 	case NO_ERROR:
 		_responder->respond_ok();
-		if (_property)
-			_engine.broadcaster()->send_property_change(_subject, _key, _value);
-		else
-			_engine.broadcaster()->send_variable_change(_subject, _key, _value);
+		_engine.broadcaster()->send_property_change(_subject, _key, _value);
 		break;
 	case NOT_FOUND:
 		_responder->respond_error((boost::format(
diff --git a/src/engine/events/SetMetadataEvent.hpp b/src/engine/events/SetMetadataEvent.hpp
index 944091b0..b33cc9ca 100644
--- a/src/engine/events/SetMetadataEvent.hpp
+++ b/src/engine/events/SetMetadataEvent.hpp
@@ -40,7 +40,7 @@ public:
 	SetMetadataEvent(Engine&              engine,
 	                 SharedPtr<Responder> responder,
 	                 SampleCount          timestamp,
-	                 bool                 property,
+	                 bool                 meta,
 	                 const Raul::URI&     subject,
 	                 const Raul::URI&     key,
 	                 const Raul::Atom&    value);
@@ -59,14 +59,14 @@ private:
 		POLYPHONIC
 	} _special_type;
 
-	bool                  _property;
-	bool                  _success;
 	Raul::URI             _subject;
 	Raul::URI             _key;
 	Raul::Atom            _value;
 	Shared::ResourceImpl* _object;
 	PatchImpl*            _patch;
 	CompiledPatch*        _compiled_patch;
+	bool                  _is_meta;
+	bool                  _success;
 };