From daf6749c34f54d18296605edbe30ccd9dfa0fe0d Mon Sep 17 00:00:00 2001
From: Alice39s <alice39s@xmsl.dev>
Date: Sun, 28 Jun 2026 05:17:59 +0900
Subject: [PATCH] fix(erlang): pass expected version to worker and fail fast on
 xdb mismatch

---
 binding/erlang/src/ip2region_sup.erl    |  4 +--
 binding/erlang/src/ip2region_worker.erl |  6 +++-
 binding/erlang/test/xdb_test.erl        | 41 ++++++++++---------------
 3 files changed, 24 insertions(+), 27 deletions(-)

diff --git a/binding/erlang/src/ip2region_sup.erl b/binding/erlang/src/ip2region_sup.erl
index 05ad9db..7b07742 100644
--- a/binding/erlang/src/ip2region_sup.erl
+++ b/binding/erlang/src/ip2region_sup.erl
@@ -67,12 +67,12 @@ pool_child_specs() ->
                 Acc
         end, [], DbConfig).
 
-make_pool_spec(PoolName, _Version, File, PoolArgsCfg) ->
+make_pool_spec(PoolName, Version, File, PoolArgsCfg) ->
     PoolArgs = [
         {strategy, fifo},
         {name, {local, PoolName}},
         {worker_module, ip2region_worker}
         | PoolArgsCfg
     ],
-    WorkerArgs = [{xdb_file, File}],
+    WorkerArgs = [{xdb_file, File}, {expected_version, Version}],
     poolboy:child_spec(PoolName, PoolArgs, WorkerArgs).
diff --git a/binding/erlang/src/ip2region_worker.erl b/binding/erlang/src/ip2region_worker.erl
index 695c1b4..90d9152 100644
--- a/binding/erlang/src/ip2region_worker.erl
+++ b/binding/erlang/src/ip2region_worker.erl
@@ -62,10 +62,14 @@ init(Args) ->
     {ok, IoDevice} = file:open(XdbFileName, [read, binary]),
     {ok, HeaderBin} = file:read(IoDevice, ?XDB_HEADER_SIZE),
     {ok, Header} = ip2region_xdb:parse_header(HeaderBin),
+    ExpectedVersion = proplists:get_value(expected_version, Args),
     case resolve_version(Header) of
-        {ok, Version} ->
+        {ok, Version} when ExpectedVersion =:= undefined; ExpectedVersion =:= Version ->
             load_vector_index(IoDevice, Version),
             {ok, #state{xdb_fd = IoDevice, version = Version}};
+        {ok, Version} ->
+            file:close(IoDevice),
+            {stop, {xdb_version_mismatch, ExpectedVersion, Version}};
         {error, Reason} ->
             file:close(IoDevice),
             {stop, Reason}
diff --git a/binding/erlang/test/xdb_test.erl b/binding/erlang/test/xdb_test.erl
index aea2439..5388f6e 100644
--- a/binding/erlang/test/xdb_test.erl
+++ b/binding/erlang/test/xdb_test.erl
@@ -5,7 +5,7 @@
 -define(IPV6_RESULT, "United States|Florida|Miami|Google LLC|US").
 
 search_test_() ->
-    {ok, _} = application:ensure_all_started(ip2region),
+    {ok, _} = ip2region_test_util:start_app(),
     A = "中国|广东省|广州市|中国电信|CN",
     Region0 = xdb:search("1.0.8.0"),
     Region1 = xdb:search(<<"1.0.8.0">>),
@@ -19,7 +19,7 @@ search_test_() ->
     ].
 
 ipv6_search_test_() ->
-    setup_ipv6(),
+    {ok, _} = ip2region_test_util:start_app(),
     [
         ?_assert(?IPV6_RESULT =:= xdb:search("2001:4860:4860::8888")),
         ?_assert(?IPV6_RESULT =:= xdb:search(<<"2001:4860:4860::8888">>)),
@@ -27,7 +27,7 @@ ipv6_search_test_() ->
     ].
 
 invalid_search_test_() ->
-    {ok, _} = application:ensure_all_started(ip2region),
+    {ok, _} = ip2region_test_util:start_app(),
     [
         ?_assertEqual({error, bad_ip_format}, xdb:search("xxx.0.8.0")),
         ?_assertEqual({error, bad_ip_format}, xdb:search("::ggg")),
@@ -35,27 +35,20 @@ invalid_search_test_() ->
     ].
 
 ipv6_pool_not_configured_test() ->
-    try application:stop(ip2region) catch _:_ -> ok end,
-    try application:unload(ip2region) catch _:_ -> ok end,
-    ok = application:load(ip2region),
-    ok = application:set_env(ip2region, db, [{ipv4, "ip2region.xdb"}]),
-    {ok, _} = application:ensure_all_started(ip2region),
+    {ok, _} = ip2region_test_util:start_app([{ipv4, "ip2region.xdb"}]),
     ?assertEqual({error, pool_not_configured}, xdb:search("2001:4860:4860::8888")).
 
-setup_ipv6() ->
-    try application:stop(ip2region) catch _:_ -> ok end,
-    try application:unload(ip2region) catch _:_ -> ok end,
-    ok = application:load(ip2region),
-    RepoRoot = repo_root(),
-    V6File = filename:join([RepoRoot, "data", "ip2region_v6.xdb"]),
-    ok = application:set_env(ip2region, db, [
-        {ipv4, "ip2region.xdb"},
-        {ipv6, V6File}
+xdb_version_mismatch_test() ->
+    {ok, _} = ip2region_test_util:start_app(),
+    V4File = filename:join([
+        ip2region_test_util:repo_root(), "binding", "erlang", "priv", "ip2region.xdb"
     ]),
-    {ok, _} = application:ensure_all_started(ip2region).
-
-repo_root() ->
-    TestDir = filename:dirname(?FILE),
-    ErlangDir = filename:dirname(TestDir),
-    BindingDir = filename:dirname(ErlangDir),
-    filename:dirname(BindingDir).
+    error_logger:tty(false),
+    try
+        ?assertEqual(
+            {error, {xdb_version_mismatch, ipv6, ipv4}},
+            ip2region_worker:start([{xdb_file, V4File}, {expected_version, ipv6}])
+        )
+    after
+        error_logger:tty(true)
+    end.