Skip to content

Feature flags: Add virgin node init support to v2 code path #6682

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 2 commits into from
Jan 6, 2023
Merged

Feature flags: Add virgin node init support to v2 code path #6682

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
9fb4e67
rabbit_feature_flags: Support virgin node init with feature flags v2
dumbbell Dec 15, 2022
80da804
rabbit_feature_flags: Export rabbit_ff_controller functions for inter…
dumbbell Jan 5, 2023
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
79 changes: 7 additions & 72 deletions deps/rabbit/src/rabbit_feature_flags.erl
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1826,15 +1826,19 @@ sync_feature_flags_with_cluster(Nodes, NodeIsVirgin) ->
%% @private

sync_feature_flags_with_cluster(Nodes, NodeIsVirgin, Timeout) ->
Clustered = Nodes =/= [],
case is_enabled(feature_flags_v2) of
true -> rabbit_ff_controller:sync_cluster();
false -> sync_cluster_v1(Nodes, NodeIsVirgin, Timeout)
true when Clustered -> rabbit_ff_controller:sync_cluster();
true when NodeIsVirgin -> rabbit_ff_controller:enable_default();
true -> ok;
false -> sync_cluster_v1(Nodes, NodeIsVirgin, Timeout)
end.

sync_cluster_v1([], NodeIsVirgin, _) ->
case NodeIsVirgin of
true ->
FeatureNames = get_forced_feature_flag_names(),
FeatureNames =
rabbit_ff_controller:get_forced_feature_flag_names(),
case remote_nodes() of
[] when FeatureNames =:= undefined ->
rabbit_log_feature_flags:debug(
Expand Down Expand Up @@ -2068,75 +2072,6 @@ do_sync_feature_flags_with_node([FeatureFlag | Rest]) ->
do_sync_feature_flags_with_node([]) ->
ok.

-spec get_forced_feature_flag_names() -> [feature_name()] | undefined.
%% @private
%% @doc
%% Returns the (possibly empty) list of feature flags the user want
%% to enable out-of-the-box when starting a node for the first time.
%%
%% Without this, the default is to enable all the supported feature
%% flags.
%%
%% There are two ways to specify that list:
%% <ol>
%% <li>Using the `$RABBITMQ_FEATURE_FLAGS' environment variable; for
%% instance `RABBITMQ_FEATURE_FLAGS=quorum_queue,mnevis'.</li>
%% <li>Using the `forced_feature_flags_on_init' configuration parameter;
%% for instance
%% `{rabbit, [{forced_feature_flags_on_init, [quorum_queue, mnevis]}]}'.</li>
%% </ol>
%%
%% The environment variable has precedence over the configuration
%% parameter.

get_forced_feature_flag_names() ->
Ret = case get_forced_feature_flag_names_from_env() of
undefined -> get_forced_feature_flag_names_from_config();
List -> List
end,
case Ret of
undefined -> ok;
[] -> rabbit_log_feature_flags:info(
"Feature flags: automatic enablement of feature "
"flags disabled (i.e. none will be enabled "
"automatically)");
_ -> rabbit_log_feature_flags:info(
"Feature flags: automatic enablement of feature "
"flags limited to the following list: ~tp", [Ret])
end,
Ret.

-spec get_forced_feature_flag_names_from_env() -> [feature_name()] | undefined.
%% @private

get_forced_feature_flag_names_from_env() ->
case rabbit_prelaunch:get_context() of
#{forced_feature_flags_on_init := ForcedFFs}
when is_list(ForcedFFs) ->
ForcedFFs;
_ ->
undefined
end.

-spec get_forced_feature_flag_names_from_config() -> [feature_name()] | undefined.
%% @private

get_forced_feature_flag_names_from_config() ->
Value = application:get_env(rabbit,
forced_feature_flags_on_init,
undefined),
case Value of
undefined ->
Value;
_ when is_list(Value) ->
case lists:all(fun is_atom/1, Value) of
true -> Value;
false -> undefined
end;
_ ->
undefined
end.

-spec verify_which_feature_flags_are_actually_enabled() ->
ok | {error, any()} | no_return().
%% @private
Expand Down
145 changes: 143 additions & 2 deletions deps/rabbit/src/rabbit_ff_controller.erl
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -33,16 +33,20 @@

-export([is_supported/1, is_supported/2,
enable/1,
enable_default/0,
check_node_compatibility/1,
sync_cluster/0,
refresh_after_app_load/0]).
refresh_after_app_load/0,
get_forced_feature_flag_names/0]).

%% Internal use only.
-export([start/0,
start_link/0,
rpc_call/5,
all_nodes/0,
running_nodes/0]).
running_nodes/0,
collect_inventory_on_nodes/1, collect_inventory_on_nodes/2,
mark_as_enabled_on_nodes/4]).

%% gen_statem callbacks.
-export([callback_mode/0,
Expand Down Expand Up @@ -96,6 +100,25 @@ enable(FeatureNames) when is_list(FeatureNames) ->
#{domain => ?RMQLOG_DOMAIN_FEAT_FLAGS}),
gen_statem:call(?LOCAL_NAME, {enable, FeatureNames}).

enable_default() ->
?LOG_DEBUG(
"Feature flags: configure initial feature flags state",
[],
#{domain => ?RMQLOG_DOMAIN_FEAT_FLAGS}),
case erlang:whereis(?LOCAL_NAME) of
Pid when is_pid(Pid) ->
%% The function is called while `rabbit' is running.
gen_statem:call(?LOCAL_NAME, enable_default);
undefined ->
%% The function is called while `rabbit' is stopped. We need to
%% start a one-off controller, again to make sure concurrent
%% changes are blocked.
{ok, Pid} = start_link(),
Ret = gen_statem:call(Pid, enable_default),
gen_statem:stop(Pid),
Ret
end.

check_node_compatibility(RemoteNode) ->
ThisNode = node(),
?LOG_DEBUG(
Expand Down Expand Up @@ -248,6 +271,8 @@ updating_feature_flag_states(

proceed_with_task({enable, FeatureNames}) ->
enable_task(FeatureNames);
proceed_with_task(enable_default) ->
enable_default_task();
proceed_with_task(sync_cluster) ->
sync_cluster_task();
proceed_with_task(refresh_after_app_load) ->
Expand Down Expand Up @@ -451,6 +476,122 @@ enable_task(FeatureNames) ->
{error, missing_clustered_nodes}
end.

enable_default_task() ->
FeatureNames = get_forced_feature_flag_names(),
case FeatureNames of
undefined ->
?LOG_DEBUG(
"Feature flags: starting an unclustered node for the first "
"time: all stable feature flags will be enabled by default",
#{domain => ?RMQLOG_DOMAIN_FEAT_FLAGS}),
{ok, Inventory} = collect_inventory_on_nodes([node()]),
#{feature_flags := FeatureFlags} = Inventory,
StableFeatureNames =
maps:fold(
fun
(FeatureName, #{stability := stable}, Acc) ->
[FeatureName | Acc];
(_FeatureName, _FeatureProps, Acc) ->
Acc
end, [], FeatureFlags),
enable_many(Inventory, StableFeatureNames);
[] ->
?LOG_DEBUG(
"Feature flags: starting an unclustered node for the first "
"time: all feature flags are forcibly left disabled from "
"the $RABBITMQ_FEATURE_FLAGS environment variable",
#{domain => ?RMQLOG_DOMAIN_FEAT_FLAGS}),
ok;
_ ->
?LOG_DEBUG(
"Feature flags: starting an unclustered node for the first "
"time: only the following feature flags specified in the "
"$RABBITMQ_FEATURE_FLAGS environment variable will be enabled: "
"~tp",
[FeatureNames],
#{domain => ?RMQLOG_DOMAIN_FEAT_FLAGS}),
{ok, Inventory} = collect_inventory_on_nodes([node()]),
enable_many(Inventory, FeatureNames)
end.

-spec get_forced_feature_flag_names() -> Ret when
Ret :: FeatureNames | undefined,
FeatureNames :: [rabbit_feature_flags:feature_name()].
%% @doc Returns the (possibly empty) list of feature flags the user wants to
%% enable out-of-the-box when starting a node for the first time.
%%
%% Without this, the default is to enable all the supported stable feature
%% flags.
%%
%% There are two ways to specify that list:
%% <ol>
%% <li>Using the `$RABBITMQ_FEATURE_FLAGS' environment variable; for
%% instance `RABBITMQ_FEATURE_FLAGS=quorum_queue,mnevis'.</li>
%% <li>Using the `forced_feature_flags_on_init' configuration parameter;
%% for instance
%% `{rabbit, [{forced_feature_flags_on_init, [quorum_queue, mnevis]}]}'.</li>
%% </ol>
%%
%% The environment variable has precedence over the configuration parameter.
%%
%% @private

get_forced_feature_flag_names() ->
Ret = case get_forced_feature_flag_names_from_env() of
undefined -> get_forced_feature_flag_names_from_config();
List -> List
end,
case Ret of
undefined ->
ok;
[] ->
?LOG_INFO(
"Feature flags: automatic enablement of feature flags "
"disabled (i.e. none will be enabled automatically)",
#{domain => ?RMQLOG_DOMAIN_FEAT_FLAGS});
_ ->
?LOG_INFO(
"Feature flags: automatic enablement of feature flags "
"limited to the following list: ~tp",
[Ret],
#{domain => ?RMQLOG_DOMAIN_FEAT_FLAGS})
end,
Ret.

-spec get_forced_feature_flag_names_from_env() -> Ret when
Ret :: FeatureNames | undefined,
FeatureNames :: [rabbit_feature_flags:feature_name()].
%% @private

get_forced_feature_flag_names_from_env() ->
case rabbit_prelaunch:get_context() of
#{forced_feature_flags_on_init := ForcedFFs}
when is_list(ForcedFFs) ->
ForcedFFs;
_ ->
undefined
end.

-spec get_forced_feature_flag_names_from_config() -> Ret when
Ret :: FeatureNames | undefined,
FeatureNames :: [rabbit_feature_flags:feature_name()].
%% @private

get_forced_feature_flag_names_from_config() ->
Value = application:get_env(
rabbit, forced_feature_flags_on_init, undefined),
case Value of
undefined ->
Value;
_ when is_list(Value) ->
case lists:all(fun is_atom/1, Value) of
true -> Value;
false -> undefined
end;
_ ->
undefined
end.

-spec sync_cluster_task() -> Ret when
Ret :: ok | {error, Reason},
Reason :: term().
Expand Down