From e99fee68c098b65ca9946e784ccc97e5b86d60e3 Mon Sep 17 00:00:00 2001
From: Thales Macedo Garitezi <thalesmg@gmail.com>
Date: Fri, 5 Jul 2024 09:46:20 -0300
Subject: [PATCH 1/2] fix(message transformation): forbid empty topic filter
 list

Fixes https://emqx.atlassian.net/browse/EMQX-12646
---
 .../src/emqx_message_transformation_schema.erl      |  2 ++
 .../test/emqx_message_transformation_tests.erl      | 13 +++++++++++++
 2 files changed, 15 insertions(+)

diff --git a/apps/emqx_message_transformation/src/emqx_message_transformation_schema.erl b/apps/emqx_message_transformation/src/emqx_message_transformation_schema.erl
index 9dee9d5b0..169743e5b 100644
--- a/apps/emqx_message_transformation/src/emqx_message_transformation_schema.erl
+++ b/apps/emqx_message_transformation/src/emqx_message_transformation_schema.erl
@@ -231,6 +231,8 @@ do_validate_unique_names([#{<<"name">> := Name} | _Rest], Acc) when is_map_key(N
 do_validate_unique_names([#{<<"name">> := Name} | Rest], Acc) ->
     do_validate_unique_names(Rest, Acc#{Name => true}).
 
+validate_unique_topics([]) ->
+    {error, <<"at least one topic filter must be defined">>};
 validate_unique_topics(Topics) ->
     Grouped = maps:groups_from_list(
         fun(T) -> T end,
diff --git a/apps/emqx_message_transformation/test/emqx_message_transformation_tests.erl b/apps/emqx_message_transformation/test/emqx_message_transformation_tests.erl
index 3e86e3862..545773c00 100644
--- a/apps/emqx_message_transformation/test/emqx_message_transformation_tests.erl
+++ b/apps/emqx_message_transformation/test/emqx_message_transformation_tests.erl
@@ -87,6 +87,19 @@ schema_test_() ->
                     )
                 ])
             )},
+        {"topics must be non-empty",
+            ?_assertThrow(
+                {_Schema, [
+                    #{
+                        reason := <<"at least one topic filter must be defined", _/binary>>,
+                        value := [],
+                        kind := validation_error
+                    }
+                ]},
+                parse_and_check([
+                    transformation(<<"foo">>, [dummy_operation()], #{<<"topics">> => []})
+                ])
+            )},
         {"names are unique",
             ?_assertThrow(
                 {_Schema, [

From e7351d949d578d6f59e6fddceff8147d2004fcba Mon Sep 17 00:00:00 2001
From: Thales Macedo Garitezi <thalesmg@gmail.com>
Date: Fri, 5 Jul 2024 09:49:09 -0300
Subject: [PATCH 2/2] fix(schema validation): forbid empty topic filter list

---
 .../src/emqx_schema_validation.app.src              |  2 +-
 .../src/emqx_schema_validation_schema.erl           |  2 ++
 .../test/emqx_schema_validation_tests.erl           | 13 +++++++++++++
 changes/ee/fix-13420.en.md                          |  1 +
 4 files changed, 17 insertions(+), 1 deletion(-)
 create mode 100644 changes/ee/fix-13420.en.md

diff --git a/apps/emqx_schema_validation/src/emqx_schema_validation.app.src b/apps/emqx_schema_validation/src/emqx_schema_validation.app.src
index 2dfe710db..31b2a30fc 100644
--- a/apps/emqx_schema_validation/src/emqx_schema_validation.app.src
+++ b/apps/emqx_schema_validation/src/emqx_schema_validation.app.src
@@ -1,6 +1,6 @@
 {application, emqx_schema_validation, [
     {description, "EMQX Schema Validation"},
-    {vsn, "0.1.1"},
+    {vsn, "0.1.2"},
     {registered, [emqx_schema_validation_sup, emqx_schema_validation_registry]},
     {mod, {emqx_schema_validation_app, []}},
     {applications, [
diff --git a/apps/emqx_schema_validation/src/emqx_schema_validation_schema.erl b/apps/emqx_schema_validation/src/emqx_schema_validation_schema.erl
index fa9461745..8984d1066 100644
--- a/apps/emqx_schema_validation/src/emqx_schema_validation_schema.erl
+++ b/apps/emqx_schema_validation/src/emqx_schema_validation_schema.erl
@@ -259,6 +259,8 @@ do_validate_unique_schema_checks(
 do_validate_unique_schema_checks([_Check | Rest], Seen, Duplicated) ->
     do_validate_unique_schema_checks(Rest, Seen, Duplicated).
 
+validate_unique_topics([]) ->
+    {error, <<"at least one topic filter must be defined">>};
 validate_unique_topics(Topics) ->
     Grouped = maps:groups_from_list(
         fun(T) -> T end,
diff --git a/apps/emqx_schema_validation/test/emqx_schema_validation_tests.erl b/apps/emqx_schema_validation/test/emqx_schema_validation_tests.erl
index a75e4b556..d6e18da92 100644
--- a/apps/emqx_schema_validation/test/emqx_schema_validation_tests.erl
+++ b/apps/emqx_schema_validation/test/emqx_schema_validation_tests.erl
@@ -117,6 +117,19 @@ schema_test_() ->
                     )
                 ])
             )},
+        {"topics must be non-empty",
+            ?_assertThrow(
+                {_Schema, [
+                    #{
+                        reason := <<"at least one topic filter must be defined", _/binary>>,
+                        value := [],
+                        kind := validation_error
+                    }
+                ]},
+                parse_and_check([
+                    validation(<<"foo">>, [sql_check()], #{<<"topics">> => []})
+                ])
+            )},
         {"foreach expression is not allowed",
             ?_assertThrow(
                 {_Schema, [
diff --git a/changes/ee/fix-13420.en.md b/changes/ee/fix-13420.en.md
new file mode 100644
index 000000000..994ee8a88
--- /dev/null
+++ b/changes/ee/fix-13420.en.md
@@ -0,0 +1 @@
+Added a schema validation to forbid empty topic filter lists when configuring a Schema Validation.