add AttributeProxy support

README.md

@@ -1,4 +1,4 @@
 # luTango - Lua binding for Tango
 
 luTango is a module providing access to [Tango Control System](https://www.tango-controls.org/) with Lua.  
-In it's current state, a basic subset of client API is available (DeviceProxy), although not all Tango types are supported.
+In it's current state, a basic subset of client API is available (DeviceProxy, AttributeProxy), although not all Tango types are supported.

src/core/lutango_core.cpp

@@ -14,6 +14,7 @@ int luaopen_lutango_core(lua_State* L)
 	lut_lua_register_log(L);
 	lut_lua_register_sys(L);
 	lut_lua_register_DeviceProxy(L);
+	lut_lua_register_AttributeProxy(L);
 
 	LUT_LOG(TRACE, "Core module table registered.");
 	

src/core/lutango_core.h

@@ -7,6 +7,7 @@
 #include <core/sys/sys.h>
 
 #include <core/tango/DeviceProxy/lut_DeviceProxy.h>
+#include <core/tango/AttributeProxy/lut_AttributeProxy.h>
 
 #ifdef __cplusplus
 extern "C"

src/core/tango/AttributeProxy/lut_AttributeProxy.cpp

@@ -0,0 +1,141 @@
+#include "lut_AttributeProxy.h"
+
+// WRAPPER CLASS --------------------------------------------------------------
+AttributeProxyWrapper::AttributeProxyWrapper(const char* name)
+	: type_cached(false)
+{
+	attr = new Tango::AttributeProxy(name);
+}
+
+AttributeProxyWrapper::~AttributeProxyWrapper()
+{
+	delete attr;
+}
+
+Tango::DeviceAttribute read_attr(AttributeProxyWrapper* udata)
+{
+	Tango::DeviceAttribute attr_data = udata->attr->read();
+	udata->type_desc.type = attr_data.get_type();
+	udata->type_desc.format = attr_data.get_data_format();
+	udata->type_cached = true;
+	return attr_data;
+}
+
+// TANGO API ------------------------------------------------------------------
+int lut_AttributeProxy_state(lua_State* L)
+{
+	LUT_LOG(TRACE, "TANGO API AttributeProxy:state()");
+	AttributeProxyWrapper* udata = (AttributeProxyWrapper*)lut_getobj(L, 1);
+	std::string attr_name = udata->attr->name();
+	
+	try
+	{
+		lut_DevState(L, udata->attr->state());
+	}
+	catch(Tango::DevFailed e)
+	{
+		lut_DevFailed(L, e, attr_name.c_str());
+	}
+
+	return 1;
+}
+
+int lut_AttributeProxy_status(lua_State* L)
+{
+	LUT_LOG(TRACE, "TANGO API AttributeProxy:status()");
+	AttributeProxyWrapper* udata = (AttributeProxyWrapper*)lut_getobj(L, 1);
+	std::string attr_name = udata->attr->name();
+	
+	try
+	{
+		lua_pushstring(L, udata->attr->status().c_str());
+	}
+	catch(Tango::DevFailed e)
+	{
+		lut_DevFailed(L, e, attr_name.c_str());
+	}
+
+	return 1;
+}
+
+// LUA API --------------------------------------------------------------------
+void lut_lua_register_AttributeProxy(lua_State* L)
+{
+	// create table, register funcs and add it as AttributeProxy to lutango's table
+	lua_newtable(L);
+	luaL_register(L, NULL, lut_AttributeProxy);
+	lua_setfield(L, -2, "AttributeProxy");
+
+	LUT_LOG(INFO, "Registered AttributeProxy table");
+}
+
+int lut_AttributeProxy_create(lua_State* L)
+{
+	const char* name = luaL_checkstring(L, 1);
+
+	LUT_LOG(TRACE, "LUA API AttributeProxy:create(%s)", name);
+
+	// push userdata containing the DeviceProxy
+	AttributeProxyWrapper** udata = (AttributeProxyWrapper**)lua_newuserdata(L, sizeof(AttributeProxyWrapper*));
+	try
+	{
+		*udata = new AttributeProxyWrapper(name);
+	}
+	catch(Tango::DevFailed e)
+	{
+		lut_DevFailed(L, e, name);
+	}
+
+	// set metatable, that allows userdata proper garbage collection
+	luaL_newmetatable(L, LUT_ATTRIBUTEPROXY);
+	luaL_register(L, NULL, lut_AttributeProxy_userdata);
+	lua_setmetatable(L, -2);
+	
+	return 1;
+}
+
+int lut_AttributeProxy_destroy(lua_State* L)
+{
+	LUT_LOG(TRACE, "LUA API AttributeProxy:destroy()");
+	AttributeProxyWrapper* udata = (AttributeProxyWrapper*)lut_getobj(L, 1);
+	delete udata;
+	return 0;
+}
+
+// aka read / write
+int lut_AttributeProxy_call(lua_State* L)
+{
+	AttributeProxyWrapper* udata = (AttributeProxyWrapper*)lut_getobj(L, 1);
+	std::string attr_name = udata->attr->name();
+	
+	LUT_LOG(TRACE, "LUA API AttributeProxy(%s):call(...)", attr_name.c_str());
+
+	try
+	{
+		if(lua_isnoneornil(L, 2))
+		{
+			// called without arguments - read attribute
+			LUT_LOG(TRACE, "Reading attribute %s", attr_name.c_str());
+			unpack_attr_data(L, read_attr(udata));
+			return 1;
+		}
+		else
+		{
+			if(!udata->type_cached)
+			{
+				// no cached type mapping
+				LUT_LOG(TRACE, "Type mapping for attribute %s doesn't exist, reading first", attr_name.c_str());
+				read_attr(udata);
+			}
+
+			Tango::DeviceAttribute v = pack_attr_data(L, 2, udata->type_desc, attr_name.c_str());
+			udata->attr->write(v);
+			return 0;
+		}
+	}
+	catch(Tango::DevFailed e)
+	{
+		lut_DevFailed(L, e, attr_name.c_str());
+	}
+	return 0;
+}

src/core/tango/AttributeProxy/lut_AttributeProxy.h

@@ -0,0 +1,62 @@
+#ifndef __LUT_ATTRIBUTEPROXY_H__
+#	define __LUT_ATTRIBUTEPROXY_H__
+
+#include <string>
+#include <vector>
+
+#include <core/tango.h>
+#include <core/lua.h>
+#include <core/utils.h>
+
+#include <core/lua/object.h>
+#include <core/logging/log.h>
+
+#include <core/tango/attrdata.h>
+#include <core/tango/DevState/lut_DevState.h>
+#include <core/tango/DevFailed/lut_DevFailed.h>
+
+#define LUT_ATTRIBUTEPROXY		"lut_AttributeProxy"
+
+// Wrapper class
+class AttributeProxyWrapper
+{
+	public:
+		AttributeProxyWrapper(const char* name);
+		~AttributeProxyWrapper();
+		Tango::AttributeProxy* attr;
+		AttrTypeDescription type_desc;
+		bool type_cached;
+};
+
+Tango::DeviceAttribute read_attr(AttributeProxyWrapper* udata);
+
+// Tango API
+int lut_AttributeProxy_state(lua_State* L);
+int lut_AttributeProxy_status(lua_State* L);
+
+// Lua API
+void lut_lua_register_AttributeProxy(lua_State* L);
+int lut_AttributeProxy_create(lua_State* L);
+int lut_AttributeProxy_destroy(lua_State* L);
+int lut_AttributeProxy_call(lua_State* L);
+
+static const luaL_reg lut_AttributeProxy[] =
+{
+	// Lua API
+	{ "create", lut_AttributeProxy_create },
+	{ "call", lut_AttributeProxy_call },
+
+	// Tango API
+	{ "status", lut_AttributeProxy_status },
+	{ "state", lut_AttributeProxy_state },
+
+	{ NULL, NULL }
+};
+
+static const luaL_reg lut_AttributeProxy_userdata[] =
+{
+	{ "__gc", lut_AttributeProxy_destroy },
+	{ NULL, NULL }
+};
+
+#endif /* __LUT_ATTRIBUTEPROXY_H__ */

src/core/tango/DevState/lut_DevState.cpp

@@ -7,7 +7,7 @@ void lut_DevState(lua_State* L, Tango::DevState state)
 	load_lua_lib(L, LUTANGO);
 	lua_getglobal(L, LUTANGO);
 	
-	lua_getfield(L, 1, "DevState");
+	lua_getfield(L, -2, "DevState");
 	lua_pushnumber(L, (int)state);
 
 	lua_call(L, 1, 1);

src/init.lua

@@ -9,6 +9,7 @@ local lutango = {
 	sys = core.sys,
 	lutObject = lutObject,
 	DeviceProxy = lutObject("DeviceProxy"),
+	AttributeProxy = lutObject("AttributeProxy"),
 	DevState = require "lutango.lutDevState"
 }
 

src/lutObject.lua

@@ -7,6 +7,7 @@ local lutObject = {}
 function create_lutObject(type)
 	log(log.level.TRACE, "New lutObject for "..type)
 	local o = {
+		__is_instance = false,
 		__type = type
 	}
 
@@ -15,17 +16,26 @@ function create_lutObject(type)
 end
 
 function lutObject:__call(...)
-	log(log.level.TRACE, "New "..self.__type.."("..table.concat({...}, ", ")..")")
-	local o = {
-		__type = self.__type
-	}
+	if self.__is_instance then
+		if self.__type then
+			return try(core[self.__type].call, self.__obj, ...)
+		else
+			return nil
+		end
+	else
+		log(log.level.TRACE, "New "..self.__type.."("..table.concat({...}, ", ")..")")
+		local o = {
+			__is_instance = true,
+			__type = self.__type
+		}
 
-	if self.__type then
-		o.__obj = try(core[self.__type].create, ...)
+		if self.__type then
+			o.__obj = try(core[self.__type].create, ...)
+		end
+
+		setmetatable(o, lutObject)
+		return o
 	end
-
-	setmetatable(o, lutObject)
-	return o
 end
 
 function lutObject:__index(key)

tests/attributeproxy.lua

@@ -0,0 +1,18 @@
+local lut = require "lutango"
+lut.log:set_log_level(lut.log.level.WARNING)
+
+local ap = lut.AttributeProxy("sys/tg_test/1/ampli")
+
+print("Reading state and status")
+print("State = "..tostring(ap:state()))
+print("Status = "..ap:status())
+
+print("Reading attribute")
+local v = ap()
+print("ampli = "..v)
+
+print("Writing attribute")
+ap(v+1)
+
+print("Reading again")
+print("ampli = "..ap())