Merge pull request #2231 from rabbitmq/extract_sd_notify

Convert systemd notification to prelaunch steps

1 files changed, 12 insertions, 127 deletions

diff --git a/src/rabbit.erl b/src/rabbit.erl
index 191fbc5320..0f98e50504 100644
--- a/src/rabbit.erl
+++ b/src/rabbit.erl
@@ -373,120 +373,6 @@ run_prelaunch_second_phase() ->
     end,
     ok.
 
-%% Try to send systemd ready notification if it makes sense in the
-%% current environment. standard_error is used intentionally in all
-%% logging statements, so all this messages will end in systemd
-%% journal.
-maybe_sd_notify() ->
-    case sd_notify_ready() of
-        false ->
-            io:format(standard_error, "systemd READY notification failed, beware of timeouts~n", []);
-        _ ->
-            ok
-    end.
-
-sd_notify_ready() ->
-    case rabbit_prelaunch:get_context() of
-        #{systemd_notify_socket := Socket} when Socket =/= undefined ->
-            %% Non-empty NOTIFY_SOCKET, give it a try
-            sd_notify_legacy() orelse sd_notify_socat();
-        _ ->
-            true
-    end.
-
-sd_notify_data() ->
-    "READY=1\nSTATUS=Initialized\nMAINPID=" ++ os:getpid() ++ "\n".
-
-sd_notify_legacy() ->
-    case code:load_file(sd_notify) of
-        {module, sd_notify} ->
-            SDNotify = sd_notify,
-            SDNotify:sd_notify(0, sd_notify_data()),
-            true;
-        {error, _} ->
-            false
-    end.
-
-%% socat(1) is the most portable way the sd_notify could be
-%% implemented in erlang, without introducing some NIF. Currently the
-%% following issues prevent us from implementing it in a more
-%% reasonable way:
-%% - systemd-notify(1) is unstable for non-root users
-%% - erlang doesn't support unix domain sockets.
-%%
-%% Some details on how we ended with such a solution:
-%%   https://github.com/rabbitmq/rabbitmq-server/issues/664
-sd_notify_socat() ->
-    case sd_current_unit() of
-        {ok, Unit} ->
-            io:format(standard_error, "systemd unit for activation check: \"~s\"~n", [Unit]),
-            sd_notify_socat(Unit);
-        _ ->
-            false
-    end.
-
-socat_socket_arg("@" ++ AbstractUnixSocket) ->
-    "abstract-sendto:" ++ AbstractUnixSocket;
-socat_socket_arg(UnixSocket) ->
-    "unix-sendto:" ++ UnixSocket.
-
-sd_open_port() ->
-    #{systemd_notify_socket := Socket} = rabbit_prelaunch:get_context(),
-    true = Socket =/= undefined,
-    open_port(
-      {spawn_executable, os:find_executable("socat")},
-      [{args, [socat_socket_arg(Socket), "STDIO"]},
-       use_stdio, out]).
-
-sd_notify_socat(Unit) ->
-    try sd_open_port() of
-        Port ->
-            Port ! {self(), {command, sd_notify_data()}},
-            Result = sd_wait_activation(Port, Unit),
-            port_close(Port),
-            Result
-    catch
-        Class:Reason ->
-            io:format(standard_error, "Failed to start socat ~p:~p~n", [Class, Reason]),
-            false
-    end.
-
-sd_current_unit() ->
-    CmdOut = os:cmd("ps -o unit= -p " ++ os:getpid()),
-    case catch re:run(CmdOut, "([-.@0-9a-zA-Z]+)", [unicode, {capture, all_but_first, list}]) of
-        {'EXIT', _} ->
-            error;
-        {match, [Unit]} ->
-            {ok, Unit};
-        _ ->
-            error
-    end.
-
-sd_wait_activation(Port, Unit) ->
-    case os:find_executable("systemctl") of
-        false ->
-            io:format(standard_error, "'systemctl' unavailable, falling back to sleep~n", []),
-            timer:sleep(5000),
-            true;
-        _ ->
-            sd_wait_activation(Port, Unit, 10)
-    end.
-
-sd_wait_activation(_, _, 0) ->
-    io:format(standard_error, "Service still in 'activating' state, bailing out~n", []),
-    false;
-sd_wait_activation(Port, Unit, AttemptsLeft) ->
-    case os:cmd("systemctl show --property=ActiveState -- '" ++ Unit ++ "'") of
-        "ActiveState=activating\n" ->
-            timer:sleep(1000),
-            sd_wait_activation(Port, Unit, AttemptsLeft - 1);
-        "ActiveState=" ++ _ ->
-            true;
-        _ = Err->
-            io:format(standard_error, "Unexpected status from systemd ~p~n", [Err]),
-            false
-    end.
-
 start_it(StartType) ->
     case spawn_boot_marker() of
         {ok, Marker} ->
@@ -519,12 +405,12 @@ start_it(StartType) ->
     end.
 
 wait_for_ready_or_stopped() ->
-    ok = rabbit_prelaunch:wait_for_boot_state(ready),
-    case rabbit_prelaunch:get_boot_state() of
+    ok = rabbit_boot_state:wait_for(ready, ?BOOT_FINISH_TIMEOUT),
+    case rabbit_boot_state:get() of
         ready ->
             ok;
         _ ->
-            ok = rabbit_prelaunch:wait_for_boot_state(stopped),
+            ok = rabbit_boot_state:wait_for(stopped, ?BOOT_FINISH_TIMEOUT),
             rabbit_prelaunch:get_stop_reason()
     end.
 
@@ -548,7 +434,7 @@ stop_boot_marker(Marker) ->
 stop() ->
     case wait_for_ready_or_stopped() of
         ok ->
-            case rabbit_prelaunch:get_boot_state() of
+            case rabbit_boot_state:get() of
                 ready ->
                     rabbit_log:info("RabbitMQ is asked to stop..."),
                     do_stop(),
@@ -656,7 +542,7 @@ handle_app_error(Term) ->
 is_booting() -> is_booting(node()).
 
 is_booting(Node) when Node =:= node() ->
-    case rabbit_prelaunch:get_boot_state() of
+    case rabbit_boot_state:get() of
         booting           -> true;
         _                 -> false
     end;
@@ -855,7 +741,7 @@ is_running() -> is_running(node()).
 -spec is_running(node()) -> boolean().
 
 is_running(Node) when Node =:= node() ->
-    case rabbit_prelaunch:get_boot_state() of
+    case rabbit_boot_state:get() of
         ready       -> true;
         _           -> false
     end;
@@ -925,7 +811,7 @@ start(normal, []) ->
     %% This is important if the previous startup attempt failed after
     %% rabbitmq_prelaunch was started and the application is still
     %% running.
-    rabbit_prelaunch:set_boot_state(booting),
+    rabbit_boot_state:set(booting),
     rabbit_prelaunch:clear_stop_reason(),
 
     try
@@ -969,7 +855,7 @@ start(normal, []) ->
             mnesia:stop(),
             rabbit_prelaunch_errors:log_error(Error),
             rabbit_prelaunch:set_stop_reason(Error),
-            rabbit_prelaunch:set_boot_state(stopped),
+            rabbit_boot_state:set(stopped),
             Error;
         Class:Exception:Stacktrace ->
             mnesia:stop(),
@@ -977,7 +863,7 @@ start(normal, []) ->
               Class, Exception, Stacktrace),
             Error = {error, Exception},
             rabbit_prelaunch:set_stop_reason(Error),
-            rabbit_prelaunch:set_boot_state(stopped),
+            rabbit_boot_state:set(stopped),
             Error
     end.
 
@@ -1020,8 +906,7 @@ do_run_postlaunch_phase() ->
           end, Plugins),
 
         rabbit_log_prelaunch:debug("Marking RabbitMQ as running"),
-        rabbit_prelaunch:set_boot_state(ready),
-        maybe_sd_notify(),
+        rabbit_boot_state:set(ready),
 
         ok = rabbit_lager:broker_is_started(),
         ok = log_broker_started(
@@ -1040,7 +925,7 @@ do_run_postlaunch_phase() ->
     end.
 
 prep_stop(State) ->
-    rabbit_prelaunch:set_boot_state(stopping),
+    rabbit_boot_state:set(stopping),
     rabbit_peer_discovery:maybe_unregister(),
     State.
 
@@ -1056,7 +941,7 @@ stop(State) ->
         [] -> rabbit_prelaunch:set_stop_reason(normal);
         _  -> rabbit_prelaunch:set_stop_reason(State)
     end,
-    rabbit_prelaunch:set_boot_state(stopped),
+    rabbit_boot_state:set(stopped),
     ok.
 
 %%---------------------------------------------------------------------------