Question

以前我在ejabberd 2.1.10中使用xml：get_tag_attr_s（“type”，Packet）作为该调试行，但这在ejabberd 13.03中不再有效。可能是因为它根据文档（http://www.process-one.net/docs/exmpp/devdoc/trunk/xml.html#get_attr_s-2）被弃用，所以我尝试使用exmpp库中的函数。

我在第二个DEBUG行上遇到错误（第一个调试行工作正常）。想法如何从属性中获取价值？

代码摘录：

 on_user_send_packet(From, To, Packet) ->
  ?DEBUG("Sent packet (1): ~p", [Packet]),
  Type = exmpp_xml:get_attribute(Packet, <<"type">>, <<"unknown">>),
  ?DEBUG("Sent packet from (2): ~p", [From]),

日志：

  =INFO REPORT==== 2013-05-25 09:58:50 ===
  D(<0.1625.0>:mod_stanza_ack:59) : Sent packet (1): {xmlel,<<"message">>,
                                                [{<<"to">>,
                                                  <<"31600000002@whatsupp_dev">>},
                                                 {<<"from">>,
                                                  <<"31600000001@whatsupp_dev/webapp">>},
                                                 {<<"type">>,<<"chat">>},
                                                 {<<"id">>,<<"4834">>}],
                                                [{xmlel,<<"body">>,[],
                                                  [{xmlcdata,
                                                    <<"SHOOOOOT">>}]},
                                                 {xmlel,<<"request">>,
                                                  [{<<"xmlns">>,
                                                    <<"urn:xmpp:receipts">>}],
                                                  []}]}

 =ERROR REPORT==== 2013-05-25 09:58:50 ===
 E(<0.1625.0>:ejabberd_hooks:315) : {function_clause,
                                [{exmpp_xml,get_attribute,
                                  [{xmlel,<<"message">>,
                                    [{<<"to">>,
                                      <<"31600000002@whatsupp_dev">>},
                                     {<<"from">>,
                                      <<"31600000001@whatsupp_dev/webapp">>},
                                     {<<"type">>,<<"chat">>},
                                     {<<"id">>,<<"4834">>}],
                                    [{xmlel,<<"body">>,[],
                                      [{xmlcdata,<<"SHOOOOOT">>}]},
                                     {xmlel,<<"request">>,
                                      [{<<"xmlns">>,
                                        <<"urn:xmpp:receipts">>}],
                                      []}]},
                                   <<"from">>,<<"unknown">>],
                                  [{file,"./core/exmpp_xml.erl"},
                                   {line,1173}]},
                                 {mod_stanza_ack,on_user_send_packet,3,
                                  [{file,"mod_stanza_ack.erl"},{line,60}]},
                                 {ejabberd_hooks,run1,3,
                                  [{file,"ejabberd_hooks.erl"},
                                   {line,311}]},
                                 {ejabberd_c2s,session_established2,2,
                                  [{file,"ejabberd_c2s.erl"},{line,1136}]},
                                 {p1_fsm,handle_msg,10,
                                  [{file,"p1_fsm.erl"},{line,578}]},
                                 {proc_lib,init_p_do_apply,3,
                                  [{file,"proc_lib.erl"},{line,239}]}]}

Answer 1

您传递给Packet的{{1}}是exmpp_xml:get_attribute记录，其中包含三个字段：元素名称，属性和子元素。但是，exmpp使用五个元素（definition from here）定义xmlel记录：

xmlel

我快速浏览了ejabberd 13.03源代码，看起来% Elements. -record(xmlel, { ns = undefined :: xmlname() | undefined, declared_ns = [] :: [{xmlname(), string() | none}], name :: xmlname(), attrs = [] :: [xmlattr()], children = [] :: [#xmlel{} | xmlcdata()] | undefined }).应该可以正常工作，所以我怀疑ejabberd 13.03与exmpp不兼容。（虽然我最近并没有密切关注ejabberd的发展，所以我们会更多地了解这一点。）我认为你最好不要弄清楚为什么会xml:get_tag_attr_s打破你。

Answer 2

Pre ejabberd 13.XX

xml:get_tag_attr_s("type", Packet)

发布ejabberd 13.XX

xml:get_tag_attr_s(<<"type">>, Packet)

Answer 3

在ejabberd 16.04上它应该是

fxml：get_tag_attr_s（＆lt;＆lt;“type”＆gt;＆gt;，数据包）

使用exmpp函数时的函数子句错误

3 个答案: