User and permission management command: adopt a more suitable exit code

Apparently [1], which is the most standardized set of exit codes
we could find, includes a dedicated exit code for cases where
a user does not exist.

References #425, rabbitmq/rabbitmq-server#2363, bda0cbfdc3.

1. https://www.freebsd.org/cgi/man.cgi?query=sysexits&apropos=0&sektion=0&manpath=FreeBSD+12.0-RELEASE&arch=default&format=html

deps/rabbitmq_cli/lib/rabbitmq/cli/core/exit_codes.ex

@@ -15,13 +15,14 @@
 
 # Lists predefined error exit codes used by RabbitMQ CLI tools.
 # The codes are adopted from [1], which (according to our team's research)
-# is possibly the most standardized set of codes there is.
+# is possibly the most standardized set of command line tool exit codes there is.
 #
 # 1. https://www.freebsd.org/cgi/man.cgi?query=sysexits&apropos=0&sektion=0&manpath=FreeBSD+12.0-RELEASE&arch=default&format=html
 defmodule RabbitMQ.CLI.Core.ExitCodes do
   @exit_ok 0
   @exit_usage 64
   @exit_dataerr 65
+  @exit_nouser 67
   @exit_unavailable 69
   @exit_software 70
   @exit_tempfail 75
@@ -32,6 +33,7 @@ defmodule RabbitMQ.CLI.Core.ExitCodes do
   def exit_ok, do: @exit_ok
   def exit_usage, do: @exit_usage
   def exit_dataerr, do: @exit_dataerr
+  def exit_nouser, do: @exit_nouser
   def exit_unavailable, do: @exit_unavailable
   def exit_software, do: @exit_software
   def exit_tempfail, do: @exit_tempfail
@@ -48,6 +50,7 @@ defmodule RabbitMQ.CLI.Core.ExitCodes do
   def exit_code_for({:validation_failure, _}), do: exit_usage()
   # a special case of bad_argument
   def exit_code_for({:no_such_vhost, _}), do: exit_dataerr()
+  def exit_code_for({:no_such_user, _}), do: exit_nouser()
   def exit_code_for({:badrpc_multi, :timeout, _}), do: exit_tempfail()
   def exit_code_for({:badrpc, :timeout}), do: exit_tempfail()
   def exit_code_for({:badrpc, {:timeout, _}}), do: exit_tempfail()

deps/rabbitmq_cli/lib/rabbitmq/cli/ctl/commands/change_password_command.ex

@@ -58,7 +58,7 @@ defmodule RabbitMQ.CLI.Ctl.Commands.ChangePasswordCommand do
     {:error, %{"result" => "error", "node" => node_name, "message" => "User #{username} does not exists"}}
   end
   def output({:error, {:no_such_user, username}}, _) do
-    {:error, ExitCodes.exit_software(), "User \"#{username}\" does not exist"}
+    {:error, ExitCodes.exit_nouser(), "User \"#{username}\" does not exist"}
   end
   use RabbitMQ.CLI.DefaultOutput
 

deps/rabbitmq_cli/lib/rabbitmq/cli/ctl/commands/clear_permissions_command.ex

@@ -14,7 +14,7 @@
 ## Copyright (c) 2007-2020 VMware, Inc. or its affiliates.  All rights reserved.
 
 defmodule RabbitMQ.CLI.Ctl.Commands.ClearPermissionsCommand do
-  alias RabbitMQ.CLI.Core.{DocGuide, Helpers}
+  alias RabbitMQ.CLI.Core.{DocGuide, ExitCodes, Helpers}
 
   @behaviour RabbitMQ.CLI.CommandBehaviour
 
@@ -40,7 +40,7 @@ defmodule RabbitMQ.CLI.Ctl.Commands.ClearPermissionsCommand do
     {:error, %{"result" => "error", "node" => node_name, "message" => "Virtual host #{vhost} does not exist"}}
   end
   def output({:error, {:no_such_user, username}}, _) do
-    {:error, "User #{username} does not exist"}
+    {:error, ExitCodes.exit_nouser(), "User #{username} does not exist"}
   end
   def output({:error, {:no_such_vhost, vhost}}, _) do
     {:error, "Virtual host #{vhost} does not exist"}

deps/rabbitmq_cli/lib/rabbitmq/cli/ctl/commands/clear_topic_permissions_command.ex

@@ -14,7 +14,7 @@
 ## Copyright (c) 2007-2020 VMware, Inc. or its affiliates.  All rights reserved.
 
 defmodule RabbitMQ.CLI.Ctl.Commands.ClearTopicPermissionsCommand do
-  alias RabbitMQ.CLI.Core.{DocGuide, Helpers}
+  alias RabbitMQ.CLI.Core.{DocGuide, ExitCodes, Helpers}
 
   @behaviour RabbitMQ.CLI.CommandBehaviour
 
@@ -59,7 +59,7 @@ defmodule RabbitMQ.CLI.Ctl.Commands.ClearTopicPermissionsCommand do
     {:error, %{"result" => "error", "node" => node_name, "message" => "Virtual host #{vhost} does not exist"}}
   end
   def output({:error, {:no_such_user, username}}, _) do
-    {:error, "User #{username} does not exist"}
+    {:error, ExitCodes.exit_nouser(), "User #{username} does not exist"}
   end
   def output({:error, {:no_such_vhost, vhost}}, _) do
     {:error, "Virtual host #{vhost} does not exist"}

deps/rabbitmq_cli/lib/rabbitmq/cli/ctl/commands/delete_user_command.ex

@@ -35,7 +35,7 @@ defmodule RabbitMQ.CLI.Ctl.Commands.DeleteUserCommand do
     {:error, %{"result" => "error", "node" => node_name, "message" => "User #{username} does not exists"}}
   end
   def output({:error, {:no_such_user, username}}, _) do
-    {:error, ExitCodes.exit_software(), "User \"#{username}\" does not exist"}
+    {:error, ExitCodes.exit_nouser(), "User \"#{username}\" does not exist"}
   end
   use RabbitMQ.CLI.DefaultOutput
 

deps/rabbitmq_cli/lib/rabbitmq/cli/ctl/commands/set_permissions_command.ex

@@ -14,7 +14,7 @@
 ## Copyright (c) 2007-2020 VMware, Inc. or its affiliates.  All rights reserved.
 
 defmodule RabbitMQ.CLI.Ctl.Commands.SetPermissionsCommand do
-  alias RabbitMQ.CLI.Core.{DocGuide, Helpers}
+  alias RabbitMQ.CLI.Core.{DocGuide, ExitCodes, Helpers}
 
   @behaviour RabbitMQ.CLI.CommandBehaviour
 
@@ -54,7 +54,7 @@ defmodule RabbitMQ.CLI.Ctl.Commands.SetPermissionsCommand do
     {:error, %{"result" => "error", "node" => node_name, "message" => "Virtual host #{vhost} does not exist"}}
   end
   def output({:error, {:no_such_user, username}}, _) do
-    {:error, "User #{username} does not exist"}
+    {:error, ExitCodes.exit_nouser(), "User #{username} does not exist"}
   end
   def output({:error, {:no_such_vhost, vhost}}, _) do
     {:error, "Virtual host #{vhost} does not exist"}

deps/rabbitmq_cli/lib/rabbitmq/cli/ctl/commands/set_topic_permissions_command.ex

@@ -14,7 +14,7 @@
 ## Copyright (c) 2007-2020 VMware, Inc. or its affiliates.  All rights reserved.
 
 defmodule RabbitMQ.CLI.Ctl.Commands.SetTopicPermissionsCommand do
-  alias RabbitMQ.CLI.Core.{DocGuide, Helpers}
+  alias RabbitMQ.CLI.Core.{DocGuide, ExitCodes, Helpers}
 
   @behaviour RabbitMQ.CLI.CommandBehaviour
 
@@ -48,7 +48,7 @@ defmodule RabbitMQ.CLI.Ctl.Commands.SetTopicPermissionsCommand do
     {:error, %{"result" => "error", "node" => node_name, "message" => "Virtual host #{vhost} does not exist"}}
   end
   def output({:error, {:no_such_user, username}}, _) do
-    {:error, "User #{username} does not exist"}
+    {:error, ExitCodes.exit_nouser(), "User #{username} does not exist"}
   end
   def output({:error, {:no_such_vhost, vhost}}, _) do
     {:error, "Virtual host #{vhost} does not exist"}

deps/rabbitmq_cli/lib/rabbitmq/cli/ctl/commands/set_user_tags_command.ex

@@ -40,7 +40,7 @@ defmodule RabbitMQ.CLI.Ctl.Commands.SetUserTagsCommand do
     {:error, %{"result" => "error", "node" => node_name, "message" => "User #{username} does not exists"}}
   end
   def output({:error, {:no_such_user, username}}, _) do
-    {:error, ExitCodes.exit_software(), "User \"#{username}\" does not exist"}
+    {:error, ExitCodes.exit_nouser(), "User \"#{username}\" does not exist"}
   end
   use RabbitMQ.CLI.DefaultOutput
 

deps/rabbitmq_cli/test/rabbitmqctl_test.exs

@@ -131,7 +131,7 @@ defmodule RabbitMQCtlTest do
 
   test "An errored command returns an error code" do
     command = ["delete_user", "voldemort"]
-    capture_io(:stderr, fn -> error_check(command, exit_software()) end)
+    capture_io(:stderr, fn -> error_check(command, exit_nouser()) end)
   end
 
   test "A malformed command with an option as the first command-line arg fails gracefully" do