rabbitmq-server/deps/rabbitmq_cli/lib/rabbitmqctl.ex

## The contents of this file are subject to the Mozilla Public License
## Version 1.1 (the "License"); you may not use this file except in
## compliance with the License. You may obtain a copy of the License
## at http://www.mozilla.org/MPL/
##
## Software distributed under the License is distributed on an "AS IS"
## basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
## the License for the specific language governing rights and
## limitations under the License.
##
## The Original Code is RabbitMQ.
##
## The Initial Developer of the Original Code is GoPivotal, Inc.
## Copyright (c) 2007-2016 Pivotal Software, Inc.  All rights reserved.


defmodule RabbitMQCtl do
  alias RabbitMQ.CLI.Distribution,  as: Distribution

  alias RabbitMQ.CLI.Ctl.Commands.HelpCommand, as: HelpCommand
  alias RabbitMQ.CLI.Output, as: Output
  alias RabbitMQ.CLI.ExitCodes, as: ExitCodes

  import RabbitMQ.CLI.Ctl.Helpers
  import  RabbitMQ.CLI.Ctl.Parser

  def main(["--auto-complete", "./rabbitmqctl " <> str]) do
    auto_complete(str)
  end
  def main(["--auto-complete", "rabbitmqctl " <> str]) do
    auto_complete(str)
  end
  def main(unparsed_command) do
    {parsed_cmd, parsed_options, invalid} = parse(unparsed_command)

    case {is_command?(parsed_cmd), invalid} do
      ## No such command
      {false, _}  ->
        usage_string = HelpCommand.all_usage()
        {:error, ExitCodes.exit_usage, usage_string};
      ## Invalid options
      {_, [_|_]}  ->
        error = validation_error({:bad_option, invalid}, unparsed_command);
      ## Command valid
      {true, []}  ->
        options = parsed_options |> merge_all_defaults |> normalize_node
        Distribution.start(options)

        [command_name | arguments] = parsed_cmd
        command = commands[command_name]
        case invalid_flags(command, options) do
          [] ->
            case run_command(options, command, arguments) do
              {:error, _, _} = err ->
                err;
              {:validation_failure, err} ->
                validation_error(err, unparsed_command);
              output  ->
                formatter = get_formatter(command, options)
                printer = get_printer(options)

                output
                |> Output.format_output(formatter, options)
                |> Output.print_output(printer, options)
            end;
          result ->
            error = validation_error({:bad_option, result}, unparsed_command);
        end
    end
    |> handle_shutdown
  end

  def handle_shutdown({:error, exit_code, output}) do
    output_device = case exit_code == ExitCodes.exit_ok do
      true  -> :stdio;
      false -> :stderr
    end
    for line <- List.flatten([output]) do
      IO.puts(output_device, line)
    end
    exit_program(exit_code)
  end
  def handle_shutdown(_) do
    exit_program(ExitCodes.exit_ok)
  end

  def auto_complete(str) do
    AutoComplete.complete(str)
    |> Stream.map(&IO.puts/1) |> Stream.run
    exit_program(ExitCodes.exit_ok)
  end

  def merge_all_defaults(%{} = options) do
    options
    |> merge_defaults_node
    |> merge_defaults_timeout
    |> merge_defaults_longnames
  end

  defp merge_defaults_node(%{} = opts), do: Map.merge(%{node: get_rabbit_hostname}, opts)

  defp merge_defaults_timeout(%{} = opts), do: Map.merge(%{timeout: :infinity}, opts)

  defp merge_defaults_longnames(%{} = opts), do: Map.merge(%{longnames: false}, opts)

  defp normalize_node(%{node: node} = opts) do
    Map.merge(opts, %{node: parse_node(node)})
  end

  defp maybe_connect_to_rabbitmq(HelpCommand, _), do: nil
  defp maybe_connect_to_rabbitmq(_, node) do
    connect_to_rabbitmq(node)
  end

  defp run_command(options, command, arguments) do
    {arguments, options} = command.merge_defaults(arguments, options)
    case command.validate(arguments, options) do
      :ok ->
        print_banner(command, arguments, options)
        maybe_connect_to_rabbitmq(command, options[:node])
        try do
          command.run(arguments, options) |> command.output(options)
        catch error_type, error ->
          {:error, ExitCodes.exit_software,
           to_string(:io_lib.format("Error: ~n~p~n Stacktrace ~p~n",
                                    [error, System.stacktrace()]))}
        end
      {:validation_failure, _} = err -> err
    end
  end

  defp get_formatter(command, %{formatter: formatter}) do
    module_name = Module.safe_concat("RabbitMQ.CLI.Formatters", Mix.Utils.camelize(formatter))
    case Code.ensure_loaded(module_name) do
      {:module, _}      -> module_name;
      {:error, :nofile} -> default_formatter(command)
    end
  end
  defp get_formatter(command, _) do
    default_formatter(command)
  end

  def get_printer(%{printer: printer}) do
    module_name = String.to_atom("RabbitMQ.CLI.Printers." <>
                                 Mix.Utils.camelize(printer))
    case Code.ensure_loaded(module_name) do
      {:module, _}      -> module_name;
      {:error, :nofile} -> default_printer
    end
  end
  def get_printer(_) do
    default_printer
  end

  def default_printer() do
    RabbitMQ.CLI.Printers.StdIO
  end

  def default_formatter(command) do
    case function_exported?(command, :formatter, 0) do
      true  -> command.formatter;
      false -> RabbitMQ.CLI.Formatters.Inspect
    end
  end

  defp print_banner(command, args, opts) do
    case command.banner(args, opts) do
     nil -> nil
     banner -> IO.inspect banner
    end
  end

  defp validation_error(err_detail, unparsed_command) do
    {[command_name | _], _, _} = parse(unparsed_command)
    err = format_validation_error(err_detail, command_name) # TODO format the error better
    base_error = "Error: #{err}\nGiven:\n\t#{unparsed_command |> Enum.join(" ")}"

    usage = case is_command?(command_name) do
      true  ->
        command = commands[command_name]
        HelpCommand.base_usage(HelpCommand.program_name(), command)
      false ->
        HelpCommand.all_usage()
    end

    message = base_error <> "\n" <> usage
    {:error, ExitCodes.exit_code_for({:validation_failure, err_detail}), message}
  end

  defp format_validation_error(:not_enough_args, _), do: "not enough arguments."
  defp format_validation_error({:not_enough_args, detail}, _), do: "not enough arguments. #{detail}"
  defp format_validation_error(:too_many_args, _), do: "too many arguments."
  defp format_validation_error({:too_many_args, detail}, _), do: "too many arguments. #{detail}"
  defp format_validation_error(:bad_argument, _), do: "Bad argument."
  defp format_validation_error({:bad_argument, detail}, _), do: "Bad argument. #{detail}"
  defp format_validation_error({:bad_option, opts}, command_name) do
    header = case is_command?(command_name) do
      true  -> "Invalid options for this command:";
      false -> "Invalid options:"
    end
    Enum.join([header | for {key, val} <- opts do "#{key} : #{val}" end], "\n")
  end
  defp format_validation_error(err, _), do: inspect err

  defp invalid_flags(command, opts) do
    Map.take(opts, Map.keys(opts) -- (command.flags ++ global_flags))
    |> Map.to_list
  end

  defp exit_program(code) do
    :net_kernel.stop
    exit({:shutdown, code})
  end
end