Implement wait command

deps/rabbitmq_cli/lib/clear_permissions_command.ex

@@ -24,13 +24,13 @@ defmodule ClearPermissionsCommand do
   def validate([], _) do
     {:validation_failure, :not_enough_args}
   end
-  def switches(), do: []
-
   def validate([_|_] = args, _) when length(args) > 1 do
     {:validation_failure, :too_many_args}
   end
   def validate([_], _), do: :ok
 
+  def switches(), do: []
+
   def run([username], %{node: node_name, vhost: vhost}) do
     node_name
     |> Helpers.parse_node

deps/rabbitmq_cli/lib/parser.ex

@@ -31,7 +31,7 @@ defmodule Parser do
   defp build_switches(default) do
     Enum.reduce(Helpers.commands,
                 default,
-                fn({_, command}, {:error, _} = err) -> err;
+                fn({_, _}, {:error, _} = err) -> err;
                   ({_, command}, switches) ->
                     command_switches = command.switches()
                     case Enum.filter(command_switches,

deps/rabbitmq_cli/lib/rabbitmqctl.ex

@@ -130,6 +130,21 @@ defmodule RabbitMQCtl do
     result
   end
 
+  defp print_standard_messages({:error, :process_not_running} = result, _) do
+    IO.puts "Error: process is not running."
+    result
+  end
+
+  defp print_standard_messages({:error, {:garbage_in_pid_file, _}} = result, _) do
+    IO.puts "Error: garbage in pid file."
+    result
+  end
+
+  defp print_standard_messages({:error, {:could_not_read_pid, err}} = result, _) do
+    IO.puts "Error: could not read pid. Detail: #{err}"
+    result
+  end
+
   defp print_standard_messages({:healthcheck_failed, message} = result, _) do
     IO.puts "Error: healthcheck failed. Message: #{message}"
     result

deps/rabbitmq_cli/lib/wait_command.ex

@@ -0,0 +1,84 @@
+## 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 WaitCommand do
+  @behaviour CommandBehaviour
+  @flags []
+
+  def merge_defaults(args, opts), do: {args, opts}
+
+  def validate([_|_] = args, _) when length(args) > 1, do: {:validation_failure, :too_many_args}  
+  def validate([], _), do: {:validation_failure, :not_enough_args}  
+  def validate([_], _), do: :ok
+
+  def switches(), do: []
+
+  def run([pid_file], %{node: node_name}) do
+    node_name
+    |> Helpers.parse_node
+    |> wait_for_application(pid_file, :rabbit_and_plugins);
+  end
+
+  def usage, do: "wait <pid_file>"
+
+  def flags, do: @flags
+
+  def banner(_, %{node: node_name}), do: "Waiting for node #{node_name} ..."
+
+  defp wait_for_application(node, pid_file, :rabbit_and_plugins) do
+      case read_pid_file(pid_file, true) do
+        {:error, _} = err -> err
+        pid ->
+          IO.puts "pid is #{pid}"
+          wait_for_startup(node, pid)
+      end
+  end
+
+  defp wait_for_startup(node, pid) do 
+    while_process_is_alive(
+      node, pid, fn() -> :rpc.call(node, :rabbit, :await_startup, []) == :ok end)
+  end
+
+  defp while_process_is_alive(node, pid, activity) do 
+    case :rabbit_misc.is_os_process_alive(pid) do
+      true  -> 
+        case activity.() do
+          true  -> :ok
+          false -> 
+            :timer.sleep(1000)
+            while_process_is_alive(node, pid, activity)
+        end
+      false -> {:error, :process_not_running}
+    end
+  end
+
+  defp read_pid_file(pid_file, wait) do
+    case {:file.read_file(pid_file), wait} do 
+      {{:ok, bin}, _} ->
+        case Integer.parse(bin) do
+          :error ->
+            {:error, {:garbage_in_pid_file, pid_file}}
+          {int, _} -> Integer.to_char_list int
+        end
+      {{:error, :enoent}, true} ->
+        :timer.sleep(1000)
+        read_pid_file(pid_file, wait)
+      {{:error, err}, _} -> 
+        {:error, {:could_not_read_pid, err}}
+    end
+  end
+
+end

deps/rabbitmq_cli/test/wait_command_test.exs

@@ -0,0 +1,47 @@
+## 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 WaitCommandTest do
+  use ExUnit.Case, async: false
+  import TestHelper
+
+  @command WaitCommand
+
+  setup_all do
+    :net_kernel.start([:rabbitmqctl, :shortnames])
+    :net_kernel.connect_node(get_rabbit_hostname)
+
+    on_exit([], fn ->
+      :erlang.disconnect_node(get_rabbit_hostname)
+      :net_kernel.stop()
+    end)
+
+    :ok
+  end
+
+  setup do
+    {:ok, opts: %{node: get_rabbit_hostname}}
+  end
+
+  test "validate: with extra arguments returns an arg count error", context do
+    assert @command.validate(["pid_file", "extra"], context[:opts]) == {:validation_failure, :too_many_args}
+    assert @command.validate([], context[:opts]) == {:validation_failure, :not_enough_args}
+  end
+
+  test "banner", context do
+    assert @command.banner([], context[:opts]) =~ ~r/Waiting for node #{get_rabbit_hostname}/
+  end
+end