如何从 ejabberd 数据包对象中获取数据？答案

【问题标题】：How to get data from ejabberd packet object?如何从 ejabberd 数据包对象中获取数据？
【发布时间】：2020-02-20 14:22:30
【问题描述】：

我有一个包含数据包数据的打印日志，我使用Packet#message.sub_els 提取子元素，它给了我这样的数组：

[
    {xmlel,<<"delay">>,[{<<"xmlns">>,<<"urn:xmpp:delay">>},{<<"stamp">>,<<"2019-10-24T08:08:15.126+00:00">>}],[]},
    {xmlel,<<"type">>,[{<<"xmlns">>,<<"urn:xmpp:media">>}],[{xmlcdata,<<"1">>}]},
    {xmlel,<<"media">>,[{<<"xmlns">>,<<"urn:xmpp:data">>}],[{xmlcdata,<<"null">>}]},
    {xmlel,<<"extra">>,[{<<"xmlns">>,<<"urn:xmpp:extra">>}],[{xmlcdata,<<"{\"type\":\"chat\",\"id\":\"5d666434ae920b04875c0a57\",\"name\":\"X003\",\"username\":\"x003\",\"status\":\"\",\"profile_picture\":\"\"}">>}]},
    {xmlel,<<"request">>,[{<<"xmlns">>,<<"urn:xmpp:receipts">>}],[]},
    {xmlel,<<"request">>,[{<<"xmlns">>,<<"urn:xmpp:read">>}],[]}
],

我想要额外的类型，媒体，额外的。等等

【问题讨论】：

标签： xml xmpp ejabberd erl ejabberd-module

【解决方案1】：

我有一些方法，我已经提取了必要的数据和属性值。

AllElm = Packet#message.sub_els,
    ?INFO_MSG("BinaryData ~p",[fxml:element_to_binary(AllElm)]),
    ?INFO_MSG("PacketsData ~p",[AllElm]),
    %Test = fxml:get_path_s(Packet, [{elem, <<"type">>}]),
Delay = fxml:get_path_s(xmpp:encode(Packet), [{elem,list_to_binary("delay")}, {attr, list_to_binary("stamp")}]),
    ?INFO_MSG("PacketsDataDelay ~p",[Delay]),
Type = fxml:get_path_s(xmpp:encode(Packet), [{elem,list_to_binary("type")}, cdata]),
    ?INFO_MSG("PacketsDataType ~p",[Type]),
Media = fxml:get_path_s(xmpp:encode(Packet), [{elem,list_to_binary("media")}, cdata]),
    ?INFO_MSG("PacketsDataMedia ~p",[Media]),
Extra = fxml:get_path_s(xmpp:encode(Packet), [{elem,list_to_binary("extra")}, cdata]),
    ?INFO_MSG("PacketsDataExtra ~p",[Extra]),

【讨论】：