Modification about conf definition

- Argument for each signal subscription. (getSignalsArgs)
- differentiation between Signal as raw signal from another API
 and virtual signal depending upon other signals
- changing way to specify function with uri that specify everythings
 that could be needed to invoke a function.

Change-Id: I8917c5ae3c2c1e3fa48ddfdda41fc75eaba32bb7
Signed-off-by: Romain Forlot <romain.forlot@iot.bzh>

12 files changed, 368 insertions, 231 deletions

diff --git a/conf.d/project/etc/sig-demoboard.json b/conf.d/project/etc/sig-demoboard.json
index c078d27..3d03f3e 100644
--- a/conf.d/project/etc/sig-demoboard.json
+++ b/conf.d/project/etc/sig-demoboard.json
@@ -1,11 +1,12 @@
 {
 	"signals": [
 		{
-			"label": "low-can/messages.vehicle.speed",
+			"id": "vehicle_speed",
+			"event": "low-can/messages.vehicle.speed",
 			"class": "temporal",
 			"unit": "km/h",
 			"frequency": 1,
-			"actions": {
+			"onReceived": {
 				"label": "Unit converter",
 				"lua": "_Unit_Converter",
 				"args": {
@@ -15,22 +16,25 @@
 			}
 		},
 		{
-			"name": "low-can/diagnostic_messages.engine.speed",
+			"id": "engine_speed",
+			"event": "low-can/diagnostic_messages.engine.speed",
 			"class": "temporal",
 			"unit": "rpm",
 			"frequency": 1
 		},
 		{
-			"name": "low-can/diagnostic_messages.fuel.level",
+			"id": "fuel_level",
+			"event": "low-can/diagnostic_messages.fuel.level",
 			"class":"temporal",
 			"unit": "litre",
 			"frequency": 1
 		},
 		{
-			"name": "low-can/diagnostic_messages.engine.load",
+			"id": "engine_load",
+			"event": "low-can/diagnostic_messages.engine.load",
 			"class":"temporal",
 			"unit": "Nm",
-			"interval": 1
+			"frequency": 1
 		}
 	]
 }
diff --git a/conf.d/project/etc/sig-doors.json b/conf.d/project/etc/sig-doors.json
index ea191e4..1d23f9a 100644
--- a/conf.d/project/etc/sig-doors.json
+++ b/conf.d/project/etc/sig-doors.json
@@ -2,10 +2,9 @@
 	"signals": [
 		{
 			"id": "rear_left_window",
-			"source": "low-can/messages.windows.rear_left.open",
+			"event": "low-can/messages.windows.rear_left.open",
 			"onReceived": {
-				"plugin": "low-can-callbacks",
-				"function": "isOpen",
+				"function": "plugin://low-can-callbacks/isOpen",
 				"args": {
 					"ojoi": "pok"
 				}
@@ -13,10 +12,9 @@
 		},
 		{
 			"id": "rear_left_door",
-			"source": "low-can/messages.doors.rear_left.open",
+			"event": "low-can/messages.doors.rear_left.open",
 			"onReceived": {
-				"plugin": "low-can-callbacks",
-				"function": "isOpen",
+				"function": "plugin://low-can-callbacks/isOpen",
 				"args": {
 					"ojoi": "pok"
 				}
@@ -24,10 +22,9 @@
 		},
 		{
 			"id": "rear_right_window",
-			"source": "low-can/messages.windows.rear_right.open",
+			"event": "low-can/messages.windows.rear_right.open",
 			"onReceived": {
-				"plugin": "low-can-callbacks",
-				"function": "isOpen",
+				"function": "plugin://low-can-callbacks/isOpen",
 				"args": {
 					"ojoi": "pok"
 				}
@@ -35,10 +32,9 @@
 		},
 		{
 			"id": "rear_right_door",
-			"source": "low-can/messages.doors.rear_right.open",
+			"event": "low-can/messages.doors.rear_right.open",
 			"onReceived": {
-				"plugin": "low-can-callbacks",
-				"function": "isOpen",
+				"function": "plugin://low-can-callbacks/isOpen",
 				"args": {
 					"ojoi": "pok"
 				}
@@ -46,10 +42,9 @@
 		},
 		{
 			"id": "front_left_window",
-			"source": "low-can/messages.windows.front_left.open",
+			"event": "low-can/messages.windows.front_left.open",
 			"onReceived": {
-				"plugin": "low-can-callbacks",
-				"function": "isOpen",
+				"function": "plugin://low-can-callbacks/isOpen",
 				"args": {
 					"ojoi": "pok"
 				}
@@ -57,10 +52,9 @@
 		},
 		{
 			"id": "front_left_door",
-			"source": "low-can/messages.doors.front_left.open",
+			"event": "low-can/messages.doors.front_left.open",
 			"onReceived": {
-				"plugin": "low-can-callbacks",
-				"function": "isOpen",
+				"function": "plugin://low-can-callbacks/isOpen",
 				"args": {
 					"ojoi": "pok"
 				}
@@ -68,10 +62,9 @@
 		},
 		{
 			"id": "front_right_window",
-			"source": "low-can/messages.windows.front_right.open",
+			"event": "low-can/messages.windows.front_right.open",
 			"onReceived": {
-				"plugin": "low-can-callbacks",
-				"function": "isOpen",
+				"function": "plugin://low-can-callbacks/isOpen",
 				"args": {
 					"ojoi": "pok"
 				}
@@ -79,10 +72,9 @@
 		},
 		{
 			"id": "front_right_door",
-			"source": "low-can/messages.doors.front_right.open",
+			"event": "low-can/messages.doors.front_right.open",
 			"onReceived": {
-				"plugin": "low-can-callbacks",
-				"function": "isOpen",
+				"function": "plugin://low-can-callbacks/isOpen",
 				"args": {
 					"ojoi": "pok"
 				}
@@ -90,13 +82,12 @@
 		},
 		{
 			"id": "rear_left",
-			"source": [
+			"depends": [
 				"rear_left_window",
 				"rear_left_door"
 			],
 			"onReceived": {
-				"plugin": "low-can-callbacks",
-				"function": "isOpen",
+				"function": "plugin://low-can-callbacks/isOpen",
 				"args": {
 					"ojoi": "pok"
 				}
@@ -104,43 +95,40 @@
 		},
 		{
 			"id": "rear_right",
-			"source": [
+			"depends": [
 				"rear_right_door",
 				"rear_right_window"
 			],
 			"onReceived": {
-				"plugin": "low-can-callbacks",
-				"function": "isOpen",
+				"function": "plugin://low-can-callbacks/isOpen",
 				"args": {}
 			}
 		},
 		{
 			"id": "front_left",
-			"source": [
+			"depends": [
 				"front_left_door",
 				"front_left_window"
 			],
 			"onReceived": {
-				"plugin": "low-can-callbacks",
-				"function": "isOpen",
+				"function": "plugin://low-can-callbacks/isOpen",
 				"args": {}
 			}
 		},
 		{
 			"id": "front_right",
-			"source": [
+			"depends": [
 				"front_right_door",
 				"front_right_window"
 			],
 			"onReceived": {
-				"plugin": "low-can-callbacks",
-				"function": "isOpen",
+				"function": "plugin://low-can-callbacks/isOpen",
 				"args": {}
 			}
 		},
 		{
 			"id": "all_doors",
-			"source": [
+			"depends": [
 				"front_left_door",
 				"front_left_window",
 				"front_right_door",
@@ -151,8 +139,7 @@
 				"rear_right_window"
 			],
 			"onReceived": {
-				"plugin": "low-can-callbacks",
-				"function": "isOpen",
+				"function": "plugin://low-can-callbacks/isOpen",
 				"args": {
 					"evtname": "doors.open"
 				}
diff --git a/conf.d/project/etc/sig-geoloc.json b/conf.d/project/etc/sig-geoloc.json
index 7fc4d29..3b0e4eb 100644
--- a/conf.d/project/etc/sig-geoloc.json
+++ b/conf.d/project/etc/sig-geoloc.json
@@ -1,136 +1,155 @@
 {
 	"signals": [
 		{
-			"label": "gps/latitude",
-			"class": "state",
+			"id": "latitude",
+			"event": "gps/location",
 			"unit": "degree",
-			"frequency": 1
+			"frequency": 1,
+			"onReceived": {
+				"function": "plugin://gps-callbacks/getLatitude"
+			}
 		},
 		{
-			"label": "gps/longitude",
-			"class": "state",
+			"id": "longitude",
+			"event": "gps/location",
 			"unit": "degree",
-			"frequency": 1
+			"frequency": 1,
+			"onReceived": {
+				"function": "plugin://gps-callbacks/getSignal",
+				"args": {
+					"what": "longitude"
+				}
+			}
 		},
 		{
-			"label": "gps/altitude",
-			"class": "state",
+			"id": "altitude",
+			"event": "gps/location",
 			"unit": "meter",
 			"frequency": 1
 		},
 		{
-			"label": "heading",
+			"id": "heading",
+			"depends": [
+				"latitude",
+				"longitude"
+			],
 			"class": "state",
 			"unit": "degree",
 			"frequency": 1,
-			"dependsOn": [
-				"gps/latitude",
-				"gps/longitude"
-			],
 			"actions": {
-				"label": "Heading calculation",
+				"id": "Heading calculation",
 				"lua": "_Heading",
 				"args": {}
 			}
 		},
 		{
-			"label": "gps/speed",
+			"id": "speed",
+			"event": "gps/location",
 			"class": "temporal",
 			"unit": "m/s",
 			"frequency": 1
 		},
 		{
-			"label": "mraa/climb",
-			"class": "state",
+			"id": "climb",
+			"event": "mraa/getclimb",
 			"unit": "degree",
 			"frequency": 1
 		},
 		{
-			"label": "mraa/roll_rate",
-			"class": "state",
+			"id": "roll_rate",
+			"event": "mraa/gyroscope",
 			"unit": "degree/s",
 			"frequency": 1
 		},
 		{
-			"label": "mraa/roll_rate",
-			"class": "state",
+			"id": "pitch_rate",
+			"event": "mraa/gyroscope",
 			"unit": "degree/s",
 			"frequency": 1
 		},
 		{
-			"label": "mraa/roll_rate",
-			"class": "state",
+			"id": "yaw_rate",
+			"event": "gps/gyroscope",
 			"unit": "degree/s",
 			"frequency": 1
 		},
 		{
-			"label": "gps/pdop",
+			"id": "pdop",
+			"event": "gps/location",
 			"frequency": 1
 		},
 		{
-			"label": "gps/hdop",
+			"id": "hdop",
+			"event": "gps/location",
 			"frequency": 1
 		},
 		{
-			"label": "gps/vdop",
+			"id": "vdop",
+			"event": "gps/location",
 			"frequency": 1
 		},
 		{
-			"label": "gps/used_satellites",
+			"id": "used_satellites",
+			"event": "gps/location",
 			"frequency": 1
 		},
 		{
-			"label": "gps/tracked_satellites",
+			"id": "tracked_satellites",
+			"event": "gps/location",
 			"frequency": 1
 		},
 		{
-			"label": "gps/visible_satellites",
+			"id": "visible_satellites",
+			"event": "gps/location",
 			"frequency": 1
 		},
 		{
-			"label": "gps/sigma_hposition",
-			"class": "state",
+			"id": "sigma_hposition",
+			"event": "gps/location",
 			"unit": "meter",
 			"frequency": 1
 		},
 		{
-			"label": "gps/sigma_altitude",
-			"class": "state",
+			"id": "sigma_altitude",
+			"event": "gps/location",
 			"unit": "meter",
 			"frequency": 1
 		},
 		{
-			"label": "gps/sigma_heading",
-			"class": "state",
+			"id": "sigma_heading",
+			"event": "gps/location",
 			"unit": "degree",
 			"frequency": 1
 		},
 		{
-			"label": "gps/sigma_speed",
+			"id": "sigma_speed",
+			"event": "gps/location",
 			"class": "temporal",
 			"unit": "m/s",
 			"frequency": 1
 		},
 		{
-			"label": "gps/sigma_climb",
-			"class": "state",
+			"id": "sigma_climb",
+			"event": "gps/location",
 			"unit": "degree",
 			"frequency": 1
 		},
 		{
-			"label": "gps/gnss_fix_status",
-			"class": "state",
+			"id": "gnss_fix_status",
+			"event": "gps/location",
 			"frequency": 1
 		},
 		{
-			"label": "gps/dr_status",
+			"id": "dr_status",
+			"event": "gps/location",
 			"class": "state",
 			"frequency": 1
 		},
 		{
-			"label": "gps/reliabilty_index",
+			"id": "reliabilty_index",
+			"event": "gps/location",
 			"class": "temporal",
 			"frequency": 1
 		}
 	]
-}
\ No newline at end of file
+}
diff --git a/conf.d/project/etc/sources.json b/conf.d/project/etc/sources.json
index 6a9657a..be99a41 100644
--- a/conf.d/project/etc/sources.json
+++ b/conf.d/project/etc/sources.json
@@ -4,14 +4,13 @@
 			"api": "low-can",
 			"info": "Low level binding to handle CAN bus communications",
 			"init": {
-				"function": "low-can/subscribe",
+				"function": "api://low-can/subscribe",
 				"args": {
 					"event": "message*"
 				}
-		},
-			"getSignal": {
-				"plugin": "low-can-callbacks",
-				"function": "subscribeToLow",
+			},
+			"getSignals": {
+				"function": "plugin://low-can-callbacks/subscribeToLow",
 				"args": {
 					"arg": "first argument"
 				}
@@ -20,13 +19,13 @@
 			"api": "gps",
 			"info": "Low level binding which retrieve Satellite positionning values",
 			"init": {
-				"function": "_LUA_Simple_Echo_Args",
+				"function": "api://gps/location",
 				"args": {
 					"arg1": "first argument"
 				}
-		},
-			"getSignal": {
-				"function": "_LUA_Simple_Echo_Args",
+			},
+			"getSignals": {
+				"function": "lua://_Simple_Echo_Args",
 				"args": {
 					"arg": "first argument"
 				}
@@ -35,13 +34,13 @@
 			"api": "mraa",
 			"info": "Low level binding which retrieve different values from several sensors like gyroscope, accelerometer, etc",
 			"init": {
-				"function": "_LUA_Simple_Echo_Args",
+				"function": "lua://_Simple_Echo_Args",
 				"args": {
 					"arg1": "first argument"
 				}
-		},
-			"getSignal": {
-				"function": "_LUA_Simple_Echo_Args",
+			},
+			"getSignals": {
+				"function": "lua://_Simple_Echo_Args",
 				"args": {
 					"arg": "first argument"
 				}
diff --git a/plugins/low-can.cpp b/plugins/low-can.cpp
index 1f528a5..8b573ba 100644
--- a/plugins/low-can.cpp
+++ b/plugins/low-can.cpp
@@ -77,15 +77,18 @@ CTLP_ONLOAD(plugin, bAppHandle)
 }
 
 CTLP_CAPI (subscribeToLow, source, argsJ, eventJ, context) {
-	json_object* signalArrayJ = NULL, *subscribeArgsJ = NULL, *subscribeFilterJ = NULL, *responseJ = NULL;
-	const char* unit = NULL;
+	json_object* dependsArrayJ = nullptr, *subscribeArgsJ = nullptr, *subscribeFilterJ = nullptr, *responseJ = nullptr, *filterJ = nullptr;
+	const char *id = nullptr, *event = nullptr, *unit = nullptr;
 	double frequency = 0;
 	int err = 0;
 
-	err = wrap_json_unpack(eventJ, "{so,s?s,s?F !}",
-		"signal", &signalArrayJ,
+	err = wrap_json_unpack(eventJ, "{ss,s?s,s?o,s?s,s?F,s?o !}",
+		"id", &id,
+		"event", &event,
+		"depends", &dependsArrayJ,
 		"unit", &unit,
-		"frequency", &frequency);
+		"frequency", &frequency,
+		"getSignalsArgs", &filterJ);
 	if(err)
 	{
 		AFB_ERROR("Problem to unpack JSON object eventJ: %s",
@@ -93,29 +96,27 @@ CTLP_CAPI (subscribeToLow, source, argsJ, eventJ, context) {
 		return err;
 	}
 
-	if(frequency > 0)
+	if(frequency > 0 && !filterJ)
+		{wrap_json_pack(&subscribeFilterJ, "{sf}", "frequency", frequency);}
+	else
+		{subscribeFilterJ = filterJ;}
+
+	std::string eventStr = std::string(event);
+	std::string lowEvent = eventStr.substr(eventStr.find("/")+1);
+	err = wrap_json_pack(&subscribeArgsJ, "{ss, so*}",
+	"event", lowEvent.c_str(),
+	"filter", subscribeFilterJ);
+	if(err)
 	{
-		wrap_json_pack(&subscribeFilterJ, "{sf}", "frequency", frequency);
+		AFB_ERROR("Error building subscription query object");
+		return err;
 	}
-
-	for (int idx = 0; idx < json_object_array_length(signalArrayJ); idx++)
+	AFB_DEBUG("Calling subscribe with %s", json_object_to_json_string_ext(subscribeArgsJ, JSON_C_TO_STRING_PRETTY));
+	err = afb_service_call_sync("low-can", "subscribe", subscribeArgsJ, &responseJ);
+	if(err)
 	{
-		json_object* aSignalJ = json_object_array_get_idx(signalArrayJ, idx);
-		err = wrap_json_pack(&subscribeArgsJ, "{ss, so*}",
-		"event", json_object_get_string(aSignalJ),
-		"filter", subscribeFilterJ);
-		if(err)
-		{
-			AFB_ERROR("Error building subscription query object");
-			return err;
-		}
-		AFB_DEBUG("Calling subscribe with %s", json_object_to_json_string_ext(subscribeArgsJ, JSON_C_TO_STRING_PRETTY));
-		err = afb_service_call_sync("low-can", "subscribe", subscribeArgsJ, &responseJ);
-		if(err)
-		{
-			AFB_ERROR("Can't find api 'low-can'");
-			return err;
-		}
+		AFB_ERROR("Can't find api 'low-can'");
+		return err;
 	}
 
 	return err;
diff --git a/signal-composer-binding/signal-composer-binding.cpp b/signal-composer-binding/signal-composer-binding.cpp
index c70941a..4f12150 100644
--- a/signal-composer-binding/signal-composer-binding.cpp
+++ b/signal-composer-binding/signal-composer-binding.cpp
@@ -39,6 +39,7 @@ void onEvent(const char *event, json_object *object)
 		sig->onReceivedCB(object);
 	}
 }
+
 /// @brief entry point for client subscription request.
 void subscribe(afb_req request)
 {
@@ -60,14 +61,19 @@ void unsubscribe(afb_req request)
 /// @brief verb that loads JSON configuration (old SigComp.json file now)
 void loadConf(afb_req request)
 {
-	json_object* args = afb_req_json(request);
-	const char* confd;
+	json_object* args = afb_req_json(request), *fileJ;
+	const char* filepath;
 
-	wrap_json_unpack(args, "{s:s}", "path", &confd);
-	if(true)
-		afb_req_success(request, NULL, NULL);
+	wrap_json_unpack(args, "{s:s}", "filepath", &filepath);
+	fileJ = json_object_from_file(filepath);
+
+	if(bindingApp::instance().loadSignals(fileJ))
+		{afb_req_fail_f(request, "Loading configuration or subscription error", "Error code: -1");}
 	else
-		afb_req_fail_f(request, "Loading configuration or subscription error", "Error code: -1");
+	{
+
+		afb_req_success(request, NULL, NULL);
+	}
 }
 
 /// @brief entry point to list available signals
@@ -79,7 +85,7 @@ void list(afb_req request)
 	for(auto& sig: allSignals)
 		{json_object_array_add(allSignalsJ, sig->toJSON());}
 
-	if(json_object_array_length(allSignalsJ))
+	if(json_object_array_length(allSignalsJ) && !execConf())
 	{
 		afb_req_success(request, allSignalsJ, NULL);
 	}
diff --git a/signal-composer-binding/signal-composer.cpp b/signal-composer-binding/signal-composer.cpp
index b29df22..151de6c 100644
--- a/signal-composer-binding/signal-composer.cpp
+++ b/signal-composer-binding/signal-composer.cpp
@@ -16,6 +16,7 @@
 */
 
 #include <string.h>
+#include <fnmatch.h>
 
 #include "signal-composer.hpp"
 
@@ -26,15 +27,23 @@ extern "C" void setSignalValueHandle(const char* aName, long long int timestamp,
 		{sig->set(timestamp, value);}
 }
 
+bool startsWith(const std::string& str, const std::string& pattern)
+{
+	size_t sep;
+	if( (sep = str.find(pattern)) != std::string::npos && !sep)
+		{return true;}
+	return false;
+}
+
 static struct pluginCBT pluginHandle = {
 	.setSignalValue = setSignalValueHandle,
 };
 
 CtlSectionT bindingApp::ctlSections_[] = {
-	[0]={.key="plugins" ,.label = "plugins", .info=nullptr,
+	[0]={.key="plugins" , .label = "plugins", .info=nullptr,
 		.loadCB=PluginConfig,
 		.handle=&pluginHandle},
-	[1]={.key="sources" ,.label = "sources", .info=nullptr,
+	[1]={.key="sources" , .label = "sources", .info=nullptr,
 		 .loadCB=loadSourcesAPI,
 		 .handle=nullptr},
 	[2]={.key="signals" , .label= "signals", .info=nullptr,
@@ -68,7 +77,7 @@ bindingApp& bindingApp::instance()
 
 SourceAPI* bindingApp::getSourceAPI(const std::string& api)
 {
-	for(auto& source: sourcesList_)
+	for(auto& source: sourcesListV_)
 	{
 		if (source.api() == api)
 			{return &source;}
@@ -76,6 +85,27 @@ SourceAPI* bindingApp::getSourceAPI(const std::string& api)
 	return nullptr;
 }
 
+std::vector<std::string> bindingApp::parseURI(const std::string& uri)
+{
+	std::vector<std::string> uriV;
+	std::string delimiters = "/";
+
+	std::string::size_type start = 0;
+	auto pos = uri.find_first_of(delimiters, start);
+	while(pos != std::string::npos)
+	{
+		if(pos != start) // ignore empty tokens
+			uriV.emplace_back(uri, start, pos - start);
+		start = pos + 1;
+		pos = uri.find_first_of(delimiters, start);
+	}
+
+	if(start < uri.length()) // ignore trailing delimiter
+	uriV.emplace_back(uri, start, uri.length() - start); // add what's left of the string
+
+	return uriV;
+}
+
 CtlActionT* bindingApp::convert2Action(const std::string& name, json_object* actionJ)
 {
 	json_object *functionArgsJ = nullptr, *action = nullptr;
@@ -88,35 +118,52 @@ CtlActionT* bindingApp::convert2Action(const std::string& name, json_object* act
 			"args", &functionArgsJ))
 	{
 		action = nullptr;
-		if(::strcasestr(function, "lua"))
+		if(startsWith(function, "lua://"))
 		{
+			std::string fName = std::string(function).substr(6);
 			wrap_json_pack(&action, "{ss,ss,so*}",
 			"label", name.c_str(),
-			"lua", function,
+			"lua", fName,
 			"args", functionArgsJ);
 		}
-		else if(strstr(function, "/"))
+		else if(startsWith(function, "api://"))
 		{
-			const char* api = strsep(&function, "/");
-			//std::string api  = functionS.substr(0, sep);
-			//std::string verb = functionS.substr(sep);
+			std::string uri = std::string(function).substr(6);
+			std::vector<std::string> uriV = bindingApp::parseURI(uri);
+			if(uriV.size() != 2)
+			{
+				AFB_ERROR("Miss something in uri either plugin name or function name. Uri has to be like: api://<plugin-name>/<function-name>");
+				return nullptr;
+			}
 			wrap_json_pack(&action, "{ss,ss,ss,so*}",
 			"label", name.c_str(),
-			"api", api,
-			"verb", function,
+			"api", uriV[0].c_str(),
+			"verb", uriV[1].c_str(),
 			"args", functionArgsJ);
 		}
-		else
+		else if(startsWith(function, "plugin://"))
 		{
+			std::string uri = std::string(function).substr(9);
+			std::vector<std::string> uriV = bindingApp::parseURI(uri);
+			if(uriV.size() != 2)
+			{
+				AFB_ERROR("Miss something in uri either plugin name or function name. Uri has to be like: plugin://<plugin-name>/<function-name>");
+				return nullptr;
+			}
 			json_object *callbackJ = nullptr;
 			wrap_json_pack(&callbackJ, "{ss,ss,so*}",
-				"plugin", plugin,
-				"function", function,
+				"plugin", uriV[0].c_str(),
+				"function", uriV[1].c_str(),
 				"args", functionArgsJ);
 			wrap_json_pack(&action, "{ss,so}",
 				"label", name.c_str(),
 				"callback", callbackJ);
 		}
+		else
+		{
+			AFB_ERROR("Wrong function uri specified. You have to specified 'lua://', 'plugin://' or 'api://'. (%s)", function);
+			return nullptr;
+		}
 	}
 	if(action) {return ActionLoad(action);}
 	return nullptr;
@@ -124,18 +171,18 @@ CtlActionT* bindingApp::convert2Action(const std::string& name, json_object* act
 
 int bindingApp::loadOneSourceAPI(json_object* sourceJ)
 {
-	json_object *initJ = nullptr, *getSignalJ = nullptr;
-	CtlActionT *initCtl = nullptr, *getSignalCtl = nullptr;
+	json_object *initJ = nullptr, *getSignalsJ = nullptr;
+	CtlActionT *initCtl = nullptr, *getSignalsCtl = nullptr;
 	const char *api, *info;
 
 	int err = wrap_json_unpack(sourceJ, "{ss,s?s,s?o,s?o !}",
 			"api", &api,
 			"info", &info,
 			"init", &initJ,
-			"getSignal", &getSignalJ);
+			"getSignals", &getSignalsJ);
 	if (err)
 	{
-		AFB_ERROR("Missing something api|[info]|[init]|[getSignal] in %s", json_object_get_string(sourceJ));
+		AFB_ERROR("Missing something api|[info]|[init]|[getSignals] in %s", json_object_get_string(sourceJ));
 		return err;
 	}
 
@@ -147,9 +194,9 @@ int bindingApp::loadOneSourceAPI(json_object* sourceJ)
 	}
 
 	if(initJ) {initCtl = convert2Action("init", initJ);}
-	if(getSignalJ) {getSignalCtl = convert2Action("getSignal", getSignalJ);}
+	if(getSignalsJ) {getSignalsCtl = convert2Action("getSignals", getSignalsJ);}
 
-	sourcesList_.push_back(SourceAPI(api, info, initCtl, getSignalCtl));
+	sourcesListV_.push_back(SourceAPI(api, info, initCtl, getSignalsCtl));
 
 	return err;
 }
@@ -192,64 +239,96 @@ int bindingApp::loadSourcesAPI(CtlSectionT* section, json_object *sourcesJ)
 
 int bindingApp::loadOneSignal(json_object* signalJ)
 {
-	json_object *onReceivedJ = nullptr, *sourcesJ = nullptr;
+	json_object *onReceivedJ = nullptr, *dependsJ = nullptr, *getSignalsArgs = nullptr;
 	CtlActionT* onReceivedCtl;
 	const char *id = nullptr,
+			   *event = nullptr,
 			   *sClass = nullptr,
 			   *unit = nullptr;
-	double frequency;
+	double frequency=0.0;
 	std::string api;
-	std::vector<std::string> sourcesV;
+	std::vector<std::string> dependsV;
 	ssize_t sep;
 
-	int err = wrap_json_unpack(signalJ, "{ss,so,s?s,s?s,s?F,s?o !}",
+	int err = wrap_json_unpack(signalJ, "{ss,s?s,s?o,s?o,s?s,s?s,s?F,s?o !}",
 			"id", &id,
-			"source", &sourcesJ,
+			"event", &event,
+			"depends", &dependsJ,
+			"getSignalsArgs", &getSignalsArgs,
 			"class", &sClass,
 			"unit", &unit,
 			"frequency", &frequency,
 			"onReceived", &onReceivedJ);
 	if (err)
 	{
-		AFB_ERROR("Missing something id|source|[class]|[unit]|[frequency]|[onReceived] in %s", json_object_get_string(signalJ));
+		AFB_ERROR("Missing something id|[event|depends]|[getSignalsArgs]|[class]|[unit]|[frequency]|[onReceived] in %s", json_object_get_string(signalJ));
 		return err;
 	}
 
-	// Process sources JSON object
-	if (json_object_get_type(sourcesJ) == json_type_array)
+	// Set default sClass is not specified
+	sClass = !sClass ? "state" : sClass;
+	unit = !unit ? "" : unit;
+
+	// Get an action handler
+	onReceivedCtl = onReceivedJ ? convert2Action("onReceived", onReceivedJ) : nullptr;
+
+	// event or depends field manadatory
+	if( (!event && !dependsJ) || (event && dependsJ) )
+	{
+		AFB_ERROR("Missing something id|[event|depends]|[getSignalsArgs]|[class]|[unit]|[frequency]|[onReceived] in %s. Or you declare event AND depends, only one of them is needed.", json_object_get_string(signalJ));
+		return -1;
+	}
+
+	// Process depends JSON object to declare virtual signal dependencies
+	if (dependsJ)
 	{
-		int count = json_object_array_length(sourcesJ);
-		for(int i = 0; i < count; i++)
+		if(json_object_get_type(dependsJ) == json_type_array)
+		{
+			int count = json_object_array_length(dependsJ);
+			for(int i = 0; i < count; i++)
+			{
+				std::string sourceStr = json_object_get_string(json_object_array_get_idx(dependsJ, i));
+				if( (sep = sourceStr.find("/")) != std::string::npos)
+				{
+					AFB_ERROR("Signal composition needs to use signal 'id', don't use full low level signal name");
+					return -1;
+				}
+				dependsV.push_back(sourceStr);
+			}
+			api = sourcesListV_.rbegin()->api();
+		}
+		else
 		{
-			std::string sourceStr = json_object_get_string(json_object_array_get_idx(sourcesJ, i));
+			std::string sourceStr = json_object_get_string(dependsJ);
 			if( (sep = sourceStr.find("/")) != std::string::npos)
 			{
 				AFB_ERROR("Signal composition needs to use signal 'id', don't use full low level signal name");
 				return -1;
 			}
-			sourcesV.push_back(sourceStr);
+			dependsV.push_back(sourceStr);
+			api = sourcesListV_.rbegin()->api();
 		}
 	}
-	else
+
+	// Declare a raw signal
+	if(event)
 	{
-		std::string sourceStr = json_object_get_string(sourcesJ);
-		if( (sep = sourceStr.find("/")) != std::string::npos)
+		std::string eventStr = std::string(event);
+		if( (sep = eventStr.find("/")) == std::string::npos)
 		{
-			api = sourceStr.substr(0, sep);
+			AFB_ERROR("Missing something in event declaration. Has to be like: <api>/<event>");
+			return -1;
 		}
-		sourcesV.push_back(sourceStr);
+		api = eventStr.substr(0, sep);
+	}
+	else
+	{
+		event = "";
 	}
-
-	// Set default sClass is not specified
-	sClass = !sClass ? "state" : sClass;
-	unit = !unit ? "" : unit;
-
-	// Get an action handler
-	onReceivedCtl = convert2Action("onReceived", onReceivedJ);
 
 	SourceAPI* src = getSourceAPI(api) ? getSourceAPI(api):getSourceAPI("signal-composer");
-	if( src != nullptr)
-		{src->addSignal(id, sourcesV, sClass, unit, frequency, onReceivedCtl);}
+	if(src != nullptr)
+	{src->addSignal(id, event, dependsV, sClass, unit, frequency, onReceivedCtl, getSignalsArgs);}
 	else
 		{err = -1;}
 
@@ -281,6 +360,11 @@ int bindingApp::loadSignals(CtlSectionT* section, json_object *signalsJ)
 	return err;
 }
 
+int bindingApp::loadSignals(json_object* signalsJ)
+{
+	return loadSignals(nullptr, signalsJ);
+}
+
 std::shared_ptr<Signal> bindingApp::searchSignal(const std::string& aName)
 {
 	std::string api;
@@ -306,7 +390,7 @@ std::shared_ptr<Signal> bindingApp::searchSignal(const std::string& aName)
 std::vector<std::shared_ptr<Signal>> bindingApp::getAllSignals()
 {
 	std::vector<std::shared_ptr<Signal>> allSignals;
-	for( auto& source : sourcesList_)
+	for( auto& source : sourcesListV_)
 	{
 		std::vector<std::shared_ptr<Signal>> srcSignals = source.getSignals();
 		allSignals.insert(allSignals.end(), srcSignals.begin(), srcSignals.end());
@@ -320,14 +404,14 @@ CtlConfigT* bindingApp::ctlConfig()
 	return ctlConfig_;
 }
 
-int bindingApp::execSubscription() const
+int bindingApp::execSubscription()
 {
 	int err = 0;
-	for(const SourceAPI& srcAPI: sourcesList_)
+	for(SourceAPI& srcAPI: sourcesListV_)
 	{
 		if (srcAPI.api() != std::string(ctlConfig_->api))
 		{
-			err += srcAPI.makeSubscription();
+			err = srcAPI.makeSubscription();
 		}
 	}
 	return err;
diff --git a/signal-composer-binding/signal-composer.hpp b/signal-composer-binding/signal-composer.hpp
index 341eaab..4050700 100644
--- a/signal-composer-binding/signal-composer.hpp
+++ b/signal-composer-binding/signal-composer.hpp
@@ -28,7 +28,7 @@ private:
 	CtlConfigT* ctlConfig_;
 
 	static CtlSectionT ctlSections_[]; ///< Config Section definition (note: controls section index should match handle retrieval in)
-	std::vector<SourceAPI> sourcesList_;
+	std::vector<SourceAPI> sourcesListV_;
 
 	explicit bindingApp(const std::string& filepath);
 	bindingApp();
@@ -37,15 +37,16 @@ private:
 	CtlActionT* convert2Action(const std::string& name, json_object* action);
 
 	int loadOneSourceAPI(json_object* sourcesJ);
-	static int loadSourcesAPI(CtlSectionT* section, json_object *sectionJ);
+	static int loadSourcesAPI(CtlSectionT* section, json_object *signalsJ);
 
 	int loadOneSignal(json_object* signalsJ);
-	static int loadSignals(CtlSectionT* section, json_object *sectionJ);
+	static int loadSignals(CtlSectionT* section, json_object *signalsJ);
 
 public:
 	static bindingApp& instance();
+	static std::vector<std::string> parseURI(const std::string& uri);
 	int loadConfig(const std::string& filepath);
-	//void loadSignalsFile(std::string signalsFile);
+	int loadSignals(json_object* signalsJ);
 
 	CtlConfigT* ctlConfig();
 	std::vector<std::shared_ptr<Signal>> getAllSignals();
@@ -53,7 +54,7 @@ public:
 	std::shared_ptr<Signal> searchSignal(const std::string& aName);
 	json_object* getSignalValue(const std::string& sig, json_object* options);
 
-	int execSubscription() const;
+	int execSubscription();
 };
 
 struct pluginCBT
diff --git a/signal-composer-binding/signal.cpp b/signal-composer-binding/signal.cpp
index ea5a324..1679a6f 100644
--- a/signal-composer-binding/signal.cpp
+++ b/signal-composer-binding/signal.cpp
@@ -24,18 +24,32 @@
 
 #define MICRO 1000000
 
+Signal::Signal(const std::string& id, const std::string& event, std::vector<std::string>& depends, const std::string& unit, double frequency, CtlActionT* onReceived, json_object* getSignalsArgs)
+:id_(id),
+ event_(event),
+ dependsSigV_(depends),
+ timestamp_(0.0),
+ value_({0,0,0,0,0,""}),
+ frequency_(frequency),
+ unit_(unit),
+ onReceived_(onReceived),
+ getSignalsArgs_(getSignalsArgs)
+{}
+
 Signal::Signal(const std::string& id,
-			std::vector<std::string>& sources,
-			const std::string& unit,
-			double frequency,
-			CtlActionT* onReceived)
+	std::vector<std::string>& depends,
+	const std::string& unit,
+	double frequency,
+	CtlActionT* onReceived)
 :id_(id),
- signalSigList_(sources),
+ event_(),
+ dependsSigV_(depends),
  timestamp_(0.0),
  value_({0,0,0,0,0,""}),
  frequency_(frequency),
  unit_(unit),
- onReceived_(onReceived)
+ onReceived_(onReceived),
+ getSignalsArgs_()
 {}
 
 Signal::operator bool() const
@@ -54,11 +68,8 @@ bool Signal::operator ==(const Signal& other) const
 bool Signal::operator ==(const std::string& aName) const
 {
 	if(! fnmatch(aName.c_str(), id_.c_str(), FNM_CASEFOLD)) {return true;}
-	for( const std::string& src : signalSigList_)
-	{
-		if(! fnmatch(aName.c_str(), src.c_str(), FNM_CASEFOLD)) {return true;}
-		if( src.find(aName) != std::string::npos) {return true;}
-	}
+	if(event_.find(aName) != std::string::npos) {return true;}
+
 	return false;
 }
 
@@ -70,24 +81,27 @@ const std::string Signal::id() const
 json_object* Signal::toJSON() const
 {
 	json_object* queryJ = nullptr;
-	std::vector<std::string> lowSignalName;
-	for (const std::string& src: signalSigList_ )
+	std::vector<std::string> dependsSignalName;
+	for (const std::string& src: dependsSigV_ )
 	{
 		ssize_t sep = src.find_first_of("/");
 		if(sep != std::string::npos)
 		{
-			lowSignalName.push_back(src.substr(sep+1));
+			dependsSignalName.push_back(src.substr(sep+1));
 		}
 	}
 	json_object* nameArray = json_object_new_array();
-	for (const std::string& lowSig: lowSignalName)
+	for (const std::string& lowSig: dependsSignalName)
 	{
 		json_object_array_add(nameArray, json_object_new_string(lowSig.c_str()));
 	}
-	wrap_json_pack(&queryJ, "{so,ss*,sf*}",
-			"signal", nameArray,
+	wrap_json_pack(&queryJ, "{ss,ss*,so*,ss*,sf*,so*}",
+			"id", id_.c_str(),
+			"event", event_.c_str(),
+			"depends", nameArray,
 			"unit", unit_.c_str(),
-			"frequency", frequency_);
+			"frequency", frequency_,
+			"getSignalsArgs", getSignalsArgs_);
 
 	return queryJ;
 }
@@ -104,6 +118,7 @@ void Signal::set(long long int timestamp, struct SignalValue& value)
 {
 	timestamp_ = timestamp;
 	value_ = value;
+	history_[timestamp_] = value_;
 }
 
 /// @brief Observer method called when a Observable Signal has changes.
@@ -112,7 +127,7 @@ void Signal::set(long long int timestamp, struct SignalValue& value)
 /// @param[in] value - value of change
 void Signal::update(long long int timestamp, struct SignalValue value)
 {
-	AFB_NOTICE("Got an update from observed signal. Timestamp: %lld, vb: %d, vn: %lf, vs: %s", timestamp, value.boolVal, value.numVal, value.strVal.c_str());
+	AFB_DEBUG("Got an update from observed signal. Timestamp: %lld, vb: %d, vn: %lf, vs: %s", timestamp, value.boolVal, value.numVal, value.strVal.c_str());
 }
 
 /// @brief Notify observers that there is a change and execute callback defined
@@ -128,11 +143,18 @@ int Signal::onReceivedCB(json_object *queryJ)
 	return err;
 }
 
-/// @brief Make a Signal observer observes a Signal observable
+/// @brief Make a Signal observer observes a Signal observable if not already
+/// present in the Observers vector.
 ///
 /// @param[in] obs - pointer to a Signal observable
 void Signal::attach(Signal* obs)
 {
+	for ( auto& sig : Observers_)
+	{
+		if (obs == sig)
+			{return;}
+	}
+
 	Observers_.push_back(obs);
 }
 
@@ -142,7 +164,7 @@ void Signal::attach(Signal* obs)
 /// @param[in] bApp - bindinApp instance
 void Signal::attachToSourceSignals(bindingApp& bApp)
 {
-	for (const std::string& srcSig: signalSigList_)
+	for (const std::string& srcSig: dependsSigV_)
 	{
 		if(srcSig.find("/") == std::string::npos)
 		{
diff --git a/signal-composer-binding/signal.hpp b/signal-composer-binding/signal.hpp
index 2088ffd..4e078fc 100644
--- a/signal-composer-binding/signal.hpp
+++ b/signal-composer-binding/signal.hpp
@@ -37,13 +37,16 @@ class Signal
 {
 private:
 	std::string id_;
-	std::vector<std::string> signalSigList_;
+	std::string event_;
+	std::vector<std::string> dependsSigV_;
 	long long int timestamp_;
 	struct SignalValue value_;
 	std::map<long long int, struct SignalValue> history_; ///< history_ - Hold signal value history in map with <timestamp, value>
 	double frequency_;
 	std::string unit_;
 	CtlActionT* onReceived_;
+	json_object* getSignalsArgs_;
+
 	std::vector<Signal*> Observers_;
 
 	void notify();
@@ -51,7 +54,8 @@ private:
 	int recursionCheck(const std::string& origId);
 
 public:
-	Signal(const std::string& id, std::vector<std::string>& sources, const std::string& unit, double frequency, CtlActionT* onReceived);
+	Signal(const std::string& id, const std::string& event, std::vector<std::string>& depends, const std::string& unit, double frequency, CtlActionT* onReceived, json_object* getSignalsArgs);
+	Signal(const std::string& id, std::vector<std::string>& depends, const std::string& unit, double frequency, CtlActionT* onReceived);
 	explicit operator bool() const;
 	bool operator==(const Signal& other) const;
 	bool operator==(const std::string& aName) const;
diff --git a/signal-composer-binding/source.cpp b/signal-composer-binding/source.cpp
index 80c59d6..1f5d588 100644
--- a/signal-composer-binding/source.cpp
+++ b/signal-composer-binding/source.cpp
@@ -20,8 +20,8 @@
 SourceAPI::SourceAPI()
 {}
 
-SourceAPI::SourceAPI(const std::string& api, const std::string& info, CtlActionT* init, CtlActionT* getSignal):
-	api_(api), info_(info), init_(init), getSignal_(getSignal)
+SourceAPI::SourceAPI(const std::string& api, const std::string& info, CtlActionT* init, CtlActionT* getSignals):
+	api_(api), info_(info), init_(init), getSignals_(getSignals)
 {}
 
 std::string SourceAPI::api() const
@@ -29,41 +29,51 @@ std::string SourceAPI::api() const
 	return api_;
 }
 
-void SourceAPI::addSignal(const std::string& id, std::vector<std::string>& sources, const std::string& sClass, const std::string& unit, double frequency, CtlActionT* onReceived)
+void SourceAPI::addSignal(const std::string& id, const std::string& event, std::vector<std::string>& depends, const std::string& sClass, const std::string& unit, double frequency, CtlActionT* onReceived, json_object* getSignalsArgs)
 {
-	std::shared_ptr<Signal> sig = std::make_shared<Signal>(id, sources, unit, frequency, onReceived);
+	std::shared_ptr<Signal> sig = std::make_shared<Signal>(id, event, depends, unit, frequency, onReceived, getSignalsArgs);
 
-	signalsList_.push_back(sig);
+	signalsMap_[sig] = false;
 }
 
 std::vector<std::shared_ptr<Signal>> SourceAPI::getSignals() const
 {
-	return signalsList_;
+	std::vector<std::shared_ptr<Signal>> signals;
+	for (auto& sig: signalsMap_)
+	{
+		signals.push_back(sig.first);
+	}
+	return signals;
 }
 
 std::shared_ptr<Signal> SourceAPI::searchSignal(const std::string& name) const
 {
-	for (auto& sig: signalsList_)
+	for (auto& sig: signalsMap_)
 	{
-		if(*sig == name) {return sig;}
+		if(*sig.first == name) {return sig.first;}
 	}
 	return nullptr;
 }
 
-int SourceAPI::makeSubscription() const
+int SourceAPI::makeSubscription()
 {
 	int err = 0;
-	if(getSignal_)
+	if(getSignals_)
 	{
-		for(std::shared_ptr<Signal> sig: signalsList_)
+		for(auto& sig: signalsMap_)
 		{
-			json_object* lowSignalNameJ = sig->toJSON();
-			if(!lowSignalNameJ)
+			json_object* signalJ = sig.first->toJSON();
+			if(!signalJ)
 			{
-				AFB_ERROR("Error building JSON query object to subscribe to for signal %s", sig->id().c_str());
-				return -1;
+				AFB_ERROR("Error building JSON query object to subscribe to for signal %s", sig.first->id().c_str());
+				err = -1;
+				break;
 			}
-			err += ActionExecOne(getSignal_, lowSignalNameJ);
+			err += sig.second ? 0:ActionExecOne(getSignals_, signalJ);
+			if(err)
+				{AFB_WARNING("Fails to subscribe to signal %s", sig.first->id().c_str());}
+			else
+				{sig.second = true;}
 		}
 	}
 
diff --git a/signal-composer-binding/source.hpp b/signal-composer-binding/source.hpp
index c295b6e..560a137 100644
--- a/signal-composer-binding/source.hpp
+++ b/signal-composer-binding/source.hpp
@@ -26,19 +26,19 @@ private:
 	std::string api_;
 	std::string info_;
 	CtlActionT* init_;
-	CtlActionT* getSignal_;
+	CtlActionT* getSignals_;
 
-	std::vector<std::shared_ptr<Signal>> signalsList_;
+	std::map<std::shared_ptr<Signal>, bool> signalsMap_;
 
 public:
 	SourceAPI();
 	SourceAPI(const std::string& api, const std::string& info, CtlActionT* init, CtlActionT* getSignal);
 
 	std::string api() const;
-	void addSignal(const std::string& id, std::vector<std::string>& sources, const std::string& sClass, const std::string& unit, double frequency, CtlActionT* onReceived);
+	void addSignal(const std::string& id, const std::string& event, std::vector<std::string>& sources, const std::string& sClass, const std::string& unit, double frequency, CtlActionT* onReceived, json_object* getSignalsArgs);
 
 	std::vector<std::shared_ptr<Signal>> getSignals() const;
 	std::shared_ptr<Signal> searchSignal(const std::string& name) const;
 
-	int makeSubscription() const;
+	int makeSubscription();
 };