From 23796c901323bf823f06f858ca14ee04e4d40f69 Mon Sep 17 00:00:00 2001
From: anlicheng <244108715@qq.com>
Date: Tue, 12 May 2026 16:53:41 +0800
Subject: [PATCH] fix outbox metadata

---
 apps/efka/src/iot/efka_iot_outbox.erl | 40 ++++++++++++++++++---------
 1 file changed, 27 insertions(+), 13 deletions(-)

diff --git a/apps/efka/src/iot/efka_iot_outbox.erl b/apps/efka/src/iot/efka_iot_outbox.erl
index 1b44b93..40a4b83 100644
--- a/apps/efka/src/iot/efka_iot_outbox.erl
+++ b/apps/efka/src/iot/efka_iot_outbox.erl
@@ -8,10 +8,10 @@
 %%%
 %%% 文件结构：
 %%% - `segment-N.log'：一个 segment 文件，按写入顺序追加保存 record。
-%%% - `metadata.term'：保存 #{write_seq => N, acked_seq => N,
-%%%   writer_segment => N}。进程启动时仍然会扫描 segment 文件，并以 segment
-%%%   文件里的真实数据作为准确信息；因此即使 metadata 落后，也不会导致跳过或
-%%%   删除未消费的数据。
+%%% - `metadata.json'：使用原始 JSON 文本保存 write_seq、acked_seq 和
+%%%   writer_segment。进程启动时仍然会扫描 segment 文件，并以 segment 文件
+%%%   里的真实数据作为准确信息；因此即使 metadata 落后，也不会导致跳过或删除
+%%%   未消费的数据。
 %%% - outbox 目录通过 open/1 的 dir 参数传入，本模块不直接读取应用环境变量。
 %%%
 %%% open/1 参数：
@@ -89,7 +89,7 @@
 
 -type outbox() :: #outbox{}.
 
--define(METADATA_FILE, "metadata.term").
+-define(METADATA_FILE, "metadata.json").
 -define(SEGMENT_PREFIX, "segment-").
 -define(SEGMENT_EXT, ".log").
 -define(RECORD_MAGIC, <<"EFKAOBX1">>).
@@ -222,18 +222,32 @@ positive_option(Key, Options) ->
 read_metadata(MetadataPath) ->
     case file:read_file(MetadataPath) of
         {ok, Bin} ->
-            safe_metadata(binary_to_term(Bin, [safe]));
+            decode_metadata(Bin);
         {error, _} ->
             {0, 0, 1}
     end.
 
+-spec decode_metadata(binary()) -> {non_neg_integer(), non_neg_integer(), pos_integer()}.
+decode_metadata(Bin) ->
+    try json:decode(Bin) of
+        Metadata ->
+            safe_metadata(Metadata)
+    catch
+        _:_Reason ->
+            {0, 0, 1}
+    end.
+
 -spec safe_metadata(term()) -> {non_neg_integer(), non_neg_integer(), pos_integer()}.
-safe_metadata(#{write_seq := WriteSeq, acked_seq := AckedSeq, writer_segment := WriterSegment})
+safe_metadata(#{
+    <<"write_seq">> := WriteSeq,
+    <<"acked_seq">> := AckedSeq,
+    <<"writer_segment">> := WriterSegment
+})
   when is_integer(WriteSeq), WriteSeq >= 0,
        is_integer(AckedSeq), AckedSeq >= 0,
        is_integer(WriterSegment), WriterSegment > 0 ->
     {WriteSeq, AckedSeq, WriterSegment};
-safe_metadata(#{write_seq := WriteSeq, acked_seq := AckedSeq})
+safe_metadata(#{<<"write_seq">> := WriteSeq, <<"acked_seq">> := AckedSeq})
   when is_integer(WriteSeq), WriteSeq >= 0, is_integer(AckedSeq), AckedSeq >= 0 ->
     {WriteSeq, AckedSeq, 1};
 safe_metadata(_) ->
@@ -246,11 +260,11 @@ persist_metadata(#outbox{
     write_seq = WriteSeq,
     acked_seq = AckedSeq
 }) ->
-    Metadata = term_to_binary(#{
-        write_seq => WriteSeq,
-        acked_seq => AckedSeq,
-        writer_segment => WriterSegment
-    }),
+    Metadata = iolist_to_binary(json:encode(#{
+        <<"write_seq">> => WriteSeq,
+        <<"acked_seq">> => AckedSeq,
+        <<"writer_segment">> => WriterSegment
+    })),
     TmpPath = MetadataPath ++ ".tmp",
     case file:write_file(TmpPath, Metadata, [write, binary]) of
         ok ->