support empty request

README.md

@@ -210,8 +210,12 @@ All the fields must be encoded in ascending order (by tag). The tags of fields c
 
 The header is a 16bit integer. It is the number of fields.
 
-Each field in field part is two 16bit integer. The first one is the tag increment. The base of tags is 0, if your tags in message in continuous, the tag increment will be zero. 
-the second one indicates the value of this field. If it is 0, the real value is encoded in data part, or minus 1 as the field value.
+Each field in field part is a 16bit integer (n). If n is zero, that means the field data is encoded in data part ;
+
+If n is even (and not zero), the value of this field is n/2-1 ;
+
+If n is odd, that means the tags is not continuous, and we should add current tag by (n+1)/2 .
+
 Read the examples below to see more details.
 
 Notice: If the tag is not declared in schema, the decoder will simply ignore the field for protocol version compatibility.
@@ -222,9 +226,9 @@ Example 1:
 person { name = "Alice" ,  age = 13, marital = false } 
 
 03 00 (fn = 3)
-00 00 00 00 (id = 0, value in data part)
-00 00 0E 00 (id = 1, value = 13)
-00 00 01 00 (id = 2, value = false)
+00 00 (id = 0, value in data part)
+1C 00 (id = 1, value = 13)
+02 00 (id = 2, value = false)
 05 00 00 00 (sizeof "Alice")
 41 6C 69 63 65 ("Alice")
 ```
@@ -241,18 +245,19 @@ person {
 }
 
 04 00 (fn = 4)
-00 00 00 00 (id = 0, value in data part)
-00 00 29 00 (id = 1, value = 40)
-01 00 00 00 (id = 3 / skip id 2, value in data part)
+00 00 (id = 0, value in data part)
+52 00 (id = 1, value = 40)
+01 00 (skip id = 2)
+00 00 (id = 3, value in data part)
 
 03 00 00 00 (sizeof "Bob")
 42 6F 62 ("Bob")
 
-17 00 00 00 (sizeof struct)
+11 00 00 00 (sizeof struct)
 03 00 (fn = 3)
-00 00 00 00 (id = 0, ref = 0)
-00 00 0E 00 (id = 1, value = 13)
-00 00 01 00 (id = 2, value = false)
+00 00 (id = 0, value in data part)
+1C 00 (id = 1, value = 13)
+02 00 (id = 2, value = false)
 05 00 00 00 (sizeof "Alice")
 41 6C 69 63 65 ("Alice")
 ```

lsproto.c

@@ -422,14 +422,16 @@ lprotocol(lua_State *L) {
 	}
 	struct sproto_type * request = sproto_protoquery(sp, tag, SPROTO_REQUEST);
 	if (request == NULL) {
-		return 0;
+		lua_pushnil(L);
+	} else {
+		lua_pushlightuserdata(L, request);
 	}
-	lua_pushlightuserdata(L, request);
 	struct sproto_type * response = sproto_protoquery(sp, tag, SPROTO_RESPONSE);
 	if (response == NULL) {
-		return 2;
+		lua_pushnil(L);
+	} else {
+		lua_pushlightuserdata(L, response);
 	}
-	lua_pushlightuserdata(L, response);
 	return 3;
 }
 

sproto.c

@@ -329,10 +329,13 @@ import_protocol(struct sproto *s, struct protocol *p, const uint8_t * stream) {
 	p->p[SPROTO_REQUEST] = NULL;
 	p->p[SPROTO_RESPONSE] = NULL;
 	int i;
-	for (i=0;i<fn;i++) {
+	int tag = 0;
+	for (i=0;i<fn;i++,tag++) {
 		int value = toword(stream + SIZEOF_FIELD * i);
-		if (value & 1)
-			return NULL;
+		if (value & 1) {
+			tag += (value-1)/2;
+			continue;
+		}
 		value = value/2 - 1;
 		switch (i) {
 		case 0:	// name
@@ -362,7 +365,7 @@ import_protocol(struct sproto *s, struct protocol *p, const uint8_t * stream) {
 		}
 	}
 
-	if (p->name == NULL || p->tag<0 || p->p[SPROTO_REQUEST] == NULL) {
+	if (p->name == NULL || p->tag<0) {
 		return NULL;
 	}
 

sproto.lua

@@ -126,11 +126,19 @@ function rpc:dispatch(...)
 	if header.type then
 		-- request
 		local proto = queryproto(self.__proto, header.type)
-		local result = core.decode(proto.request, content)
-		if header_tmp.session then
-			return "REQUEST", proto.name, result, gen_response(self, proto.response, header_tmp.session)
+		if proto.request then
+			local result = core.decode(proto.request, content)
+			if header_tmp.session then
+				return "REQUEST", proto.name, result, gen_response(self, proto.response, header_tmp.session)
+			else
+				return "REQUEST", proto.name, result
+			end
 		else
-			return "REQUEST", proto.name, result
+			if header_tmp.session then
+				return "REQUEST", proto.name, nil, gen_response(self, proto.response, header_tmp.session)
+			else
+				return "REQUEST", proto.name
+			end
 		end
 	else
 		-- response

sprotoparser.lua

@@ -271,30 +271,35 @@ local function packtype(name, t, alltypes)
 end
 
 local function packproto(name, p, alltypes)
-	if p.request == nil then
-		error(string.format("Protocol %s need request", name))
-	end
-	local request = alltypes[p.request]
-	if request == nil then
-		error(string.format("Protocol %s request type %s not found", name, p.request))
+--	if p.request == nil then
+--		error(string.format("Protocol %s need request", name))
+--	end
+	if p.request then
+		local request = alltypes[p.request]
+		if request == nil then
+			error(string.format("Protocol %s request type %s not found", name, p.request))
+		end
 	end
-	local tmp
-	if p.response then
-		tmp = {
-			"\4\0",	-- 4 fields
-			"\0\0",	-- name (id=0, ref=0)
-			packvalue(p.tag),	-- tag (tag=1)
-			packvalue(alltypes[p.request]),	-- request typename (tag=2)
-			packvalue(alltypes[p.response]),  -- response typename (tag=3)
-		}
+	local tmp = {
+		"\4\0",	-- 4 fields
+		"\0\0",	-- name (id=0, ref=0)
+		packvalue(p.tag),	-- tag (tag=1)
+	}
+	if p.request == nil and p.response == nil then
+		tmp[1] = "\2\0"
 	else
-		tmp = {
-			"\3\0",	-- 3 fields
-			"\0\0",	-- name (id=0, ref=0)
-			packvalue(p.tag),	-- tag (tag=1)
-			packvalue(alltypes[p.request]),	-- request typename (tag=2)
-		}
+		if p.request then
+			table.insert(tmp, packvalue(alltypes[p.request])) -- request typename (tag=2)
+		else
+			table.insert(tmp, "\1\0")
+		end
+		if p.response then
+			table.insert(tmp, packvalue(alltypes[p.response])) -- request typename (tag=3)
+		else
+			tmp[1] = "\3\0"
+		end
 	end
+
 	table.insert(tmp, packbytes(name))
 
 	return packbytes(table.concat(tmp))

testrpc.lua

@@ -15,6 +15,18 @@ foobar 1 {
 		ok 0 : boolean
 	}
 }
+
+foo 2 {
+	response {
+		ok 0 : boolean
+	}
+}
+
+bar 3 {}
+
+blackhole 4 {
+	request {}
+}
 ]]
 
 -- The type package must has two field : type and session
@@ -23,7 +35,7 @@ local client = sp:rpc "package"
 
 print("client request foobar")
 local req = client:request("foobar", { what = "foo" }, 1)
-print("request package size =", #req)
+print("request foobar size =", #req)
 local type, name, request, response = server:dispatch(req)
 assert(type == "REQUEST" and name == "foobar")
 print_r(request)
@@ -34,3 +46,24 @@ print("client dispatch")
 local type, session, response = client:dispatch(resp)
 assert(type == "RESPONSE" and session == 1)
 print_r(response)
+
+local req = client:request("foo", nil, 2)
+print("request foo size =", #req)
+local type, name, request, response = server:dispatch(req)
+assert(type == "REQUEST" and name == "foo" and request == nil)
+local resp = response { ok = false }
+print("response package size =", #resp)
+print("client dispatch")
+local type, session, response = client:dispatch(resp)
+assert(type == "RESPONSE" and session == 2)
+print_r(response)
+
+local req = client:request("bar")	-- bar has no response
+print("request bar size =", #req)
+local type, name, request, response = server:dispatch(req)
+assert(type == "REQUEST" and name == "bar" and request == nil and response == nil)
+
+local req = client:request "blackhole"
+print("request blackhole size = ", #req)
+
+