On a regular basis I’m seeing errors reported to Sentry such as GenServer #PID<0.106725.0> terminating

The “crash reason” reported in Sentry is {{%RuntimeError{message: "cannot fetch records from Kafka (topic=spaces partition=0 offset=520536). Reason: :not_leader_for_partition"}.

We filter our the above RuntimeError (see code below) so it’s not reported to Sentry, since it’s transient and resolves itself.

But we still end up with the GenServer error being reported.

It actually doesn’t look like an exception, so I’m not sure how we can filter it out.

Our working filtering code looks like this:

defmodule Shared.Infrastructure.Errors.EventFilter do
  @behaviour Sentry.EventFilter
  require Logger

   @spec exclude_exception?(Exception.t(), atom()) :: boolean()
  def exclude_exception?(exception, source) do
    (kafka_not_leader_for_partition_error?(exception) ||
       kafka_cannot_fetch_records?(exception) ||
       kafka_cannot_resolve_offset?(exception) ||
       invalid_path_error?(exception) ||
       malformed_request_error?(exception) ||
       no_route_error?(exception) ||
       invalid_query_error?(exception))
    |> tap(&maybe_log(exception, source, &1))
  end

  defp kafka_not_leader_for_partition_error?(exception) do
    exception_type?(exception, RuntimeError) &&
      message_includes?(exception, [
        "cannot fetch records from Kafka",
        "Reason: :not_leader_for_partition"
      ])
  end

  # <SNIP>

  defp maybe_log(exception, source, excluded) do
    if excluded do
      Logger.info(
        "Sentry exception excluded from being reported (source: #{inspect(source)}): #{inspect(exception)}"
      )
    end
  end
end

Any suggestions or pointers welcome…