Hanlder logger formatter configuration using version that doesn't support Logger.Formatter.new function

Questions / Help
1

Hello,
Im trying to configure elixir logger formatter configuration for the handler i’ve created.
Iam able to do it in elixir version >= 1.15.0 like below:

config :myapp, :logger, [
  {:handler, :file_log, :logger_std_h,
   %{
     config: %{
       file: ~c"logs/myapp.log",
       filesync_repeat_interval:
         System.get_env("FILE_LOG_SYNC_REPEAT_INTERVAL_IN_MS") |> parse_string_to_integer(5000),
       file_check:
         System.get_env("FILE_LOG_CHECK_INTERVAL_IN_MS") |> parse_string_to_integer(5000),
       max_no_bytes:
         System.get_env("FILE_LOG_MAX_SIZE_IN_MEGABYTES")
         |> parse_string_to_integer(100)
         |> megabytes_to_bytes(),
       max_no_files: parse_string_to_integer(System.get_env("FILE_LOG_MAX_NO_FILES"), 5),
       compress_on_rotate: System.get_env("FILE_LOG_COMPRESS_ON_ROTATE") |> parse_boolean(true)
     },
     formatter:
       Logger.Formatter.new(
         format: {MyApp.Logger.JsonFormatter, :format},
         metadata: [:module, :function, :line, :request_id, :all]
       )
   }}
]

but one of the project im working on is using version=v1.12.0, and the logger in elixir=1.12.0 doesnt support
Logger.Formatter.new function.
I also checked the document for logger handler, it doesnt have handler formatter config metioned.

can anyone help me on this or point me to correct reference?

Thanks !

2

What you’re configuring above it erlangs :logger library with some elixir helpers. Elixir used to have it’s own logger implementation Logger from times before erlang had :logger. Over time elixir integrated more and more with :logger to allow reuse of knowledge, tools and libraries across the ecosystem. However that means going back in elixir versions means going back in level of integration with :logger by elixir (started with 1.10), and going back far enough eventually supported otp version wouldn’t include :logger (OTP 21+).

Luckily you don’t need Logger.Formatter.new. You can likely also provide it’s return value (print it on 1.15) direct there. The helper just provides some automatic inheritence of related configrations elsewhere.

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