emqx/apps/emqx_lwm2m/src/emqx_lwm2m_xml_object.erl

79 lines
3.1 KiB
Erlang

%%--------------------------------------------------------------------
%% Copyright (c) 2020-2022 EMQ Technologies Co., Ltd. All Rights Reserved.
%%
%% Licensed under the Apache License, Version 2.0 (the "License");
%% you may not use this file except in compliance with the License.
%% You may obtain a copy of the License at
%%
%% http://www.apache.org/licenses/LICENSE-2.0
%%
%% Unless required by applicable law or agreed to in writing, software
%% distributed under the License is distributed on an "AS IS" BASIS,
%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
%% See the License for the specific language governing permissions and
%% limitations under the License.
%%--------------------------------------------------------------------
-module(emqx_lwm2m_xml_object).
-include("emqx_lwm2m.hrl").
-include_lib("xmerl/include/xmerl.hrl").
-export([ get_obj_def/2
, get_obj_def_assertive/2
, get_object_id/1
, get_object_name/1
, get_object_and_resource_id/2
, get_resource_type/2
, get_resource_name/2
, get_resource_operations/2
]).
-define(LOG(Level, Format, Args),
logger:Level("LWM2M-OBJ: " ++ Format, Args)).
get_obj_def_assertive(ObjectId, IsInt) ->
case get_obj_def(ObjectId, IsInt) of
{error, no_xml_definition} ->
erlang:throw({bad_request, {unknown_object_id, ObjectId}});
Xml ->
Xml
end.
get_obj_def(ObjectIdInt, true) ->
emqx_lwm2m_xml_object_db:find_objectid(ObjectIdInt);
get_obj_def(ObjectNameStr, false) ->
emqx_lwm2m_xml_object_db:find_name(ObjectNameStr).
get_object_id(ObjDefinition) ->
[#xmlText{value=ObjectId}] = xmerl_xpath:string("ObjectID/text()", ObjDefinition),
ObjectId.
get_object_name(ObjDefinition) ->
[#xmlText{value=ObjectName}] = xmerl_xpath:string("Name/text()", ObjDefinition),
ObjectName.
get_object_and_resource_id(ResourceNameBinary, ObjDefinition) ->
ResourceNameString = binary_to_list(ResourceNameBinary),
[#xmlText{value=ObjectId}] = xmerl_xpath:string("ObjectID/text()", ObjDefinition),
[#xmlAttribute{value=ResourceId}] = xmerl_xpath:string("Resources/Item/Name[.=\""++ResourceNameString++"\"]/../@ID", ObjDefinition),
?LOG(debug, "get_object_and_resource_id ObjectId=~p, ResourceId=~p", [ObjectId, ResourceId]),
{ObjectId, ResourceId}.
get_resource_type(ResourceIdInt, ObjDefinition) ->
ResourceIdString = integer_to_list(ResourceIdInt),
[#xmlText{value=DataType}] = xmerl_xpath:string("Resources/Item[@ID=\""++ResourceIdString++"\"]/Type/text()", ObjDefinition),
DataType.
get_resource_name(ResourceIdInt, ObjDefinition) ->
ResourceIdString = integer_to_list(ResourceIdInt),
[#xmlText{value=Name}] = xmerl_xpath:string("Resources/Item[@ID=\""++ResourceIdString++"\"]/Name/text()", ObjDefinition),
Name.
get_resource_operations(ResourceIdInt, ObjDefinition) ->
ResourceIdString = integer_to_list(ResourceIdInt),
[#xmlText{value=Operations}] = xmerl_xpath:string("Resources/Item[@ID=\""++ResourceIdString++"\"]/Operations/text()", ObjDefinition),
Operations.