skynet.service: add close (#1526)

Co-authored-by: drew.zxj <drew.zxj@alibaba-inc.com>

lualib/skynet/service.lua

@@ -34,6 +34,16 @@ function service.new(name, mainfunc, ...)
 	return address
 end
 
+function service.close(name)
+	local addr = skynet.call(get_provider(), "lua", "close", name)
+	if addr then
+        cache[name] = nil
+		skynet.kill(addr)
+		return true
+	end
+	return false
+end
+
 function service.query(name)
 	if not cache[name] then
 		cache[name] = skynet.call(get_provider(), "lua", "query", name)

service/service_provider.lua

@@ -91,6 +91,16 @@ function provider.test(name)
 	end
 end
 
+function provider.close(name)
+	local s = svr[name]
+	if not s or s.booting then
+		return skynet.ret(skynet.pack(nil))
+	end
+
+	svr[name] = nil
+	skynet.ret(skynet.pack(s.address))
+end
+
 skynet.start(function()
 	skynet.dispatch("lua", function(session, address, cmd, ...)
 		provider[cmd](...)