fix: refine error message for unsupported node.role

apps/emqx_conf/src/emqx_conf_schema.erl

@@ -589,14 +589,15 @@ fields("node") ->
             )},
         {"role",
             sc(
-                hoconsc:enum([core] ++ emqx_schema_hooks:injection_point('node.role')),
+                hoconsc:enum(node_role_symbols()),
                 #{
                     mapping => "mria.node_role",
                     default => core,
                     'readOnly' => true,
                     importance => ?IMPORTANCE_HIGH,
                     aliases => [db_role],
-                    desc => ?DESC(db_role)
+                    desc => ?DESC(db_role),
+                    validator => fun validate_node_role/1
                 }
             )},
         {"rpc_module",
@@ -1573,3 +1574,17 @@ is_ip_addr(Host, Type) ->
 
 address_type(IP) when tuple_size(IP) =:= 4 -> ipv4;
 address_type(IP) when tuple_size(IP) =:= 8 -> ipv6.
+
+node_role_symbols() ->
+    [core] ++ emqx_schema_hooks:injection_point('node.role').
+
+validate_node_role(Role) ->
+    Allowed = node_role_symbols(),
+    case lists:member(Role, Allowed) of
+        true ->
+            ok;
+        false when Role =:= replicant ->
+            throw("Node role 'replicant' is only allowed in Enterprise edition since 5.8.0");
+        false ->
+            throw("Invalid node role: " ++ atom_to_list(Role))
+    end.

apps/emqx_conf/test/emqx_conf_schema_tests.erl

@@ -685,3 +685,32 @@ dns_srv_record_is_ok_test() ->
         Value when is_map(Value),
         hocon_tconf:check_plain(emqx_conf_schema, ConfMap, #{required => false}, [node, cluster])
     ).
+
+invalid_role_test() ->
+    Conf = node_role_conf(dummy),
+    ?assertThrow(
+        {emqx_conf_schema, [#{reason := "Invalid node role: dummy"}]},
+        hocon_tconf:check_plain(emqx_conf_schema, Conf, #{required => false}, [node])
+    ).
+
+unsupported_role_test() ->
+    test_unsupported_role(emqx_release:edition()).
+
+test_unsupported_role(ee) ->
+    %% all roles are supported in ee
+    ok;
+test_unsupported_role(ce) ->
+    %% replicant role is not allowed for ce since 5.8.0
+    Conf = node_role_conf(replicant),
+    ?assertThrow(
+        {emqx_conf_schema, [
+            #{reason := "Node role 'replicant' is only allowed in Enterprise edition since 5.8.0"}
+        ]},
+        hocon_tconf:check_plain(emqx_conf_schema, Conf, #{required => false}, [node])
+    ).
+
+node_role_conf(Role0) ->
+    Role = atom_to_binary(Role0),
+    Hocon = <<"node { role =", Role/binary, ", cookie = \"cookie\", data_dir = \".\" }">>,
+    {ok, ConfMap} = hocon:binary(Hocon, #{format => map}),
+    ConfMap.