ssh_log.ex

defmodule Test do
  # runs command and logs outputs when they become available, mostly useful for long running commands that
  # provide incremental output as the command progresses
  def run_command_and_log!(host, conn, command) do
    res = Enum.reduce(
      SSHEx.stream(conn, command, channel_timeout: 10_000, exec_timeout: 3_600_000),
      %{:status => nil,:stdout => [], :stderr => []},
      fn (x, acc) ->
        case x do
          {:stdout, row} ->
            Logger.info("#{host} - stdout - #{row}")
            lines = [String.split(row, ~r/\R/)] ++ acc[:stdout]
            %{acc | :stdout => lines}
          {:stderr, row} ->
            Logger.info("#{host} - stderr - #{row}")
            lines = [String.split(row, ~r/\R/)] ++ acc[:stderr]
            %{acc | :stderr => lines}
          {:status, status} -> %{acc | :status => status}
          {:error, reason} -> raise reason
        end
      end
    )

    if res[:status] == 0 do
      %{
        :stdout => res[:stdout] |> Enum.reverse |> List.flatten |> Enum.join("\n"),
        :stderr => res[:stderr] |> Enum.reverse |> List.flatten |> Enum.join("\n"),
      }
    else
      raise "command #{command} failed: stderr: #{res[:stderr]} stdout: #{res[:stdout]}"
    end

  end
end