Do not crash on invalid metadata in deprecated backends, closes #14995

Author: josevalim

lib/logger/lib/logger/backends/handler.ex

@@ -47,7 +47,13 @@ defmodule Logger.Backends.Handler do
         %{truncate: truncate, utc_log: utc_log?} = config
         level = erlang_level_to_elixir_level(erl_level)
         message = Logger.Formatter.format_event(event, truncate)
-        timestamp = Map.get_lazy(metadata, :time, fn -> :os.system_time(:microsecond) end)
+
+        timestamp =
+          case metadata do
+            %{time: time} when is_integer(time) and time >= 0 -> time
+            _ -> :os.system_time(:microsecond)
+          end
+
         date_time_ms = Logger.Formatter.system_time_to_date_time_ms(timestamp, utc_log?)
         metadata = [erl_level: erl_level] ++ erlang_metadata_to_elixir_metadata(metadata)
         event = {level, gl, {Logger, message, date_time_ms, metadata}}

lib/logger/test/logger/backends/handler_test.exs

@@ -116,6 +116,12 @@ defmodule Logger.Backends.HandlerTest do
     Logger.Backends.Internal.configure(Logger.Backends.Console, metadata: [])
   end
 
+  test "ignores invalid Erlang metadata" do
+    assert capture_log(fn -> :logger.info("ok", %{time: "bad"}) end) =~ "ok"
+  after
+    Logger.Backends.Internal.configure(Logger.Backends.Console, metadata: [])
+  end
+
   test "uses reporting callback with Elixir inspection" do
     assert capture_log(fn ->
              callback = fn %{hello: :world} -> {"~p~n", [:formatted]} end