Change the default location of the 'enabled_plugins' file

apps/rabbitmq_prelaunch/src/rabbit_prelaunch.erl

@@ -91,12 +91,16 @@ do_run() ->
 
     %% Complete context now that we have the final environment loaded.
     Context2 = rabbit_env:get_context_after_reloading_env(Context1),
-    ?assertMatch(#{}, Context2),
-    store_context(Context2),
-    rabbit_env:log_context(Context2),
+
+    %% Migrate the enabled_plugins file to the new location if necessary
+    Context3 = rabbit_prelaunch_plugins:maybe_migrate_enabled_plugins_file(Context2),
+
+    ?assertMatch(#{}, Context3),
+    store_context(Context3),
+    rabbit_env:log_context(Context3),
     ok = setup_shutdown_func(),
 
-    Context = Context2#{initial_pass => IsInitialPass},
+    Context = Context3#{initial_pass => IsInitialPass},
 
     rabbit_env:context_to_code_path(Context),
     rabbit_env:context_to_app_env_vars(Context),

apps/rabbitmq_prelaunch/src/rabbit_prelaunch_plugins.erl

@@ -0,0 +1,40 @@
+-module(rabbit_prelaunch_plugins).
+
+-include_lib("kernel/include/file.hrl").
+
+-export([maybe_migrate_enabled_plugins_file/1]).
+
+-define(ENABLED_PLUGINS_FILENAME, "enabled_plugins").
+
+-spec maybe_migrate_enabled_plugins_file(map()) -> map().
+maybe_migrate_enabled_plugins_file(#{enabled_plugins_file := EnabledPluginsFile} = Context)
+  when EnabledPluginsFile =/= undefined ->
+    Context;
+maybe_migrate_enabled_plugins_file(#{os_type := {unix, _},
+                                     config_base_dir := ConfigBaseDir,
+                                     data_dir := DataDir} = Context) ->
+    ModernLocation = filename:join(DataDir, ?ENABLED_PLUGINS_FILENAME),
+    LegacyLocation = filename:join(ConfigBaseDir, ?ENABLED_PLUGINS_FILENAME),
+    case {filelib:is_regular(ModernLocation),
+          file:read_file_info(LegacyLocation)} of
+        {false, {ok, #file_info{access = read_write}}} ->
+            rabbit_log_prelaunch:info("NOTICE: Using 'enabled_plugins' file"
+                                      " from ~p. Please migrate this file"
+                                      " to its new location, ~p, as the"
+                                      " previous location is deprecated.",
+                                      [LegacyLocation, ModernLocation]),
+            Context#{enabled_plugins_file := LegacyLocation};
+        {false, {ok, #file_info{access = read}}} ->
+            {ok, _} = file:copy(LegacyLocation, ModernLocation),
+            rabbit_log_prelaunch:info("NOTICE: An 'enabled_plugins' file was"
+                                      " found at ~p but was not read and"
+                                      " writable. It has been copied to its"
+                                      " new location at ~p and any changes"
+                                      " to plugin status will be reflected"
+                                      " there.", [LegacyLocation, ModernLocation]),
+            Context#{enabled_plugins_file := ModernLocation};
+        _ ->
+            Context#{enabled_plugins_file := ModernLocation}
+    end;
+maybe_migrate_enabled_plugins_file(#{data_dir := DataDir} = Context) ->
+    Context#{enabled_plugins_file := filename:join(DataDir, ?ENABLED_PLUGINS_FILENAME)}.

src/rabbit_plugins.erl

@@ -17,6 +17,7 @@
 -module(rabbit_plugins).
 -include_lib("rabbit_common/include/rabbit.hrl").
 -include_lib("stdlib/include/zip.hrl").
+-include_lib("kernel/include/file.hrl").
 
 -export([setup/0, active/0, read_enabled/1, list/1, list/2, dependencies/3, running_plugins/0]).
 -export([ensure/1]).
@@ -26,6 +27,7 @@
 
 % Export for testing purpose.
 -export([is_version_supported/2, validate_plugins/2]).
+
 %%----------------------------------------------------------------------------
 
 -type plugin_name() :: atom().
@@ -99,7 +101,7 @@ plugins_dir() ->
 
 -spec enabled_plugins_file() -> file:filename().
 enabled_plugins_file() ->
-     case application:get_env(rabbit, enabled_plugins_file) of
+    case application:get_env(rabbit, enabled_plugins_file) of
         {ok, Val} ->
             Val;
         _ ->

test/rabbit_prelaunch_plugins_SUITE.erl

@@ -0,0 +1,188 @@
+%% 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
+%% https://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) 2019-2020 VMware, Inc. or its affiliates.  All rights reserved.
+%%
+
+-module(rabbit_prelaunch_plugins_SUITE).
+
+-include_lib("common_test/include/ct.hrl").
+-include_lib("eunit/include/eunit.hrl").
+-include_lib("kernel/include/file.hrl").
+
+-compile(export_all).
+
+-export([all/0,
+         suite/0,
+         groups/0,
+         init_per_group/2,
+         end_per_group/2,
+         init_per_testcase/2,
+         end_per_testcase/2,
+         check_enabled_plugins_file_passthrough/1,
+         check_enabled_plugins_file_modern/1,
+         check_enabled_plugins_file_default/1,
+         check_enabled_plugins_file_legacy/1,
+         check_enabled_plugins_file_copy/1]).
+
+all() ->
+    [
+     {group, maybe_migrate_enabled_plugins_file_tests}
+    ].
+
+suite() ->
+    [{timetrap, {seconds, 10}}].
+
+groups() ->
+    [
+     {maybe_migrate_enabled_plugins_file_tests, [],
+      [
+       check_enabled_plugins_file_passthrough,
+       check_enabled_plugins_file_modern,
+       check_enabled_plugins_file_default,
+       check_enabled_plugins_file_legacy,
+       check_enabled_plugins_file_copy
+      ]}
+    ].
+
+init_per_group(maybe_migrate_enabled_plugins_file_tests, Config) ->
+    case os:type() of
+        {unix, _} ->
+            PrivDir = proplists:get_value(priv_dir, Config),
+            RabbitConfigBaseDir = filename:join([PrivDir, "etc", "rabbitmq"]),
+            LegacyFile = filename:join(RabbitConfigBaseDir, "enabled_plugins"),
+            RabbitDataDir = filename:join([PrivDir, "var", "lib", "rabbitmq"]),
+            ModernFile = filename:join(RabbitDataDir, "enabled_plugins"),
+            [{rabbit_config_base_dir, RabbitConfigBaseDir},
+             {rabbit_data_dir, RabbitDataDir},
+             {legacy_file, LegacyFile},
+             {modern_file, ModernFile} | Config];
+        _ ->
+            {skip, "enabled_plugins file fallback behavior does not apply to Windows"}
+    end;
+init_per_group(_, Config) ->
+    Config.
+
+end_per_group(_, Config) ->
+    Config.
+
+init_per_testcase(check_enabled_plugins_file_modern, Config) ->
+    ok = cleanup_enabled_plugins_files(Config),
+    RabbitDataDir = proplists:get_value(rabbit_data_dir, Config),
+    create_enabled_plugins_file(Config, RabbitDataDir, 8#600);
+init_per_testcase(check_enabled_plugins_file_default, Config) ->
+    ok = cleanup_enabled_plugins_files(Config),
+    Config;
+init_per_testcase(check_enabled_plugins_file_legacy, Config) ->
+    ok = cleanup_enabled_plugins_files(Config),
+    RabbitConfigBaseDir = proplists:get_value(rabbit_config_base_dir, Config),
+    create_enabled_plugins_file(Config, RabbitConfigBaseDir, 8#600);
+init_per_testcase(check_enabled_plugins_file_copy, Config) ->
+    ok = cleanup_enabled_plugins_files(Config),
+    RabbitConfigBaseDir = proplists:get_value(rabbit_config_base_dir, Config),
+    create_enabled_plugins_file(Config, RabbitConfigBaseDir, 8#400);
+init_per_testcase(_, Config) ->
+    Config.
+
+end_per_testcase(_, Config) ->
+    Config.
+
+check_enabled_plugins_file_passthrough(_) ->
+    Context = #{enabled_plugins_file => "/some/dir/enabled_plugins"},
+    ?assertMatch(#{enabled_plugins_file := "/some/dir/enabled_plugins"},
+                 rabbit_prelaunch_plugins:maybe_migrate_enabled_plugins_file(Context)).
+
+check_enabled_plugins_file_modern(Config) ->
+    DataDir = proplists:get_value(rabbit_data_dir, Config),
+    ConfigBaseDir = proplists:get_value(rabbit_config_base_dir, Config),
+    ExpectedLocation = filename:join(DataDir, "enabled_plugins"),
+    true = filelib:is_regular(ExpectedLocation),
+
+    Context = #{os_type => {unix, linux},
+                config_base_dir => ConfigBaseDir,
+                data_dir => DataDir,
+                enabled_plugins_file => undefined},
+    ?assertMatch(#{enabled_plugins_file := ExpectedLocation},
+                 rabbit_prelaunch_plugins:maybe_migrate_enabled_plugins_file(Context)).
+
+check_enabled_plugins_file_default(Config) ->
+    DataDir = proplists:get_value(rabbit_data_dir, Config),
+    ConfigBaseDir = proplists:get_value(rabbit_config_base_dir, Config),
+    ExpectedLocation = filename:join(DataDir, "enabled_plugins"),
+    false = filelib:is_regular(ExpectedLocation),
+    false = filelib:is_regular(filename:join(ConfigBaseDir, "enabled_plugins")),
+
+    Context = #{os_type => {unix, linux},
+                config_base_dir => ConfigBaseDir,
+                data_dir => DataDir,
+                enabled_plugins_file => undefined},
+    ?assertMatch(#{enabled_plugins_file := ExpectedLocation},
+                 rabbit_prelaunch_plugins:maybe_migrate_enabled_plugins_file(Context)).
+
+check_enabled_plugins_file_legacy(Config) ->
+    DataDir = proplists:get_value(rabbit_data_dir, Config),
+    ConfigBaseDir = proplists:get_value(rabbit_config_base_dir, Config),
+    false = filelib:is_regular(filename:join(DataDir, "enabled_plugins")),
+    ExpectedLocation = filename:join(ConfigBaseDir, "enabled_plugins"),
+    {ok, #file_info{access = read_write}} = file:read_file_info(ExpectedLocation),
+
+    Context = #{os_type => {unix, linux},
+                config_base_dir => ConfigBaseDir,
+                data_dir => DataDir,
+                enabled_plugins_file => undefined},
+    ?assertMatch(#{enabled_plugins_file := ExpectedLocation},
+                 rabbit_prelaunch_plugins:maybe_migrate_enabled_plugins_file(Context)).
+
+check_enabled_plugins_file_copy(Config) ->
+    DataDir = proplists:get_value(rabbit_data_dir, Config),
+    ConfigBaseDir = proplists:get_value(rabbit_config_base_dir, Config),
+    ExpectedLocation = filename:join(DataDir, "enabled_plugins"),
+    false = filelib:is_regular(ExpectedLocation),
+    {ok, #file_info{access = read}} = file:read_file_info(
+                                        filename:join(ConfigBaseDir,
+                                                      "enabled_plugins")),
+
+    Context = #{os_type => {unix, linux},
+                config_base_dir => ConfigBaseDir,
+                data_dir => DataDir,
+                enabled_plugins_file => undefined},
+    ?assertMatch(#{enabled_plugins_file := ExpectedLocation},
+                 rabbit_prelaunch_plugins:maybe_migrate_enabled_plugins_file(Context)),
+    {ok, File} = file:read_file(ExpectedLocation),
+    ?assertEqual("[rabbitmq_management].", unicode:characters_to_list(File)).    
+
+create_enabled_plugins_file(Config, Location, Perm) ->
+    EnabledPluginsFile = filename:join(Location, "enabled_plugins"),
+    FileContent = io_lib:format("[rabbitmq_management].", []),
+    ok = file:write_file(EnabledPluginsFile, FileContent),
+    ok = file:change_mode(EnabledPluginsFile, Perm),
+    [{enabled_plugins_file, EnabledPluginsFile} | Config].
+
+cleanup_enabled_plugins_files(Config) ->
+    LegacyFile = proplists:get_value(legacy_file, Config),
+    ok = delete_if_present(LegacyFile),
+    ok = filelib:ensure_dir(LegacyFile),
+    ModernFile = proplists:get_value(modern_file, Config),
+    ok = delete_if_present(ModernFile),
+    ok = filelib:ensure_dir(ModernFile),
+    ok.
+
+delete_if_present(Filename) ->
+    case file:read_file_info(Filename) of
+        {ok, #file_info{type = regular}} ->
+            file:delete(Filename);
+        {ok, _} ->
+            {error, not_regular_file};
+        _ ->
+            ok
+    end.