allow Mojo::IOLoop to signal when it is shutting down gracefully

mojolicious · Feb 17, 2015 · b563152 · b563152
1 parent 7cf093a
commit b563152
Show file tree

Hide file tree

Showing 5 changed files with 28 additions and 8 deletions.
diff --git a/Changes b/Changes
@@ -8,6 +8,7 @@
   - Removed accept_interval, lock_file and lock_timeout parameters from
     Hypntoad.
   - Added stop_gracefully method to Mojo::IOLoop.
+  - Added finish event to Mojo::IOLoop.
   - Reduced idle CPU usage of Mojo::IOLoop and Mojo::Server::Prefork.
   - Improved app generator command to use current best practices.
   - Fixed bug in Mojo::IOLoop where connection limits were not properly

diff --git a/lib/Mojo/IOLoop.pm b/lib/Mojo/IOLoop.pm
@@ -1,5 +1,5 @@
 package Mojo::IOLoop;
-use Mojo::Base -base;
+use Mojo::Base 'Mojo::EventEmitter';
 
 # "Professor: Amy, technology isn't intrinsically good or evil. It's how it's
 #             used. Like the death ray."
@@ -143,7 +143,7 @@ sub stop { _instance(shift)->reactor->stop }
 
 sub stop_gracefully {
   my $self = _instance(shift)->_not_accepting;
-  $self->{stop} ||= $self->recurring(1 => \&_stop);
+  $self->{stop} ||= $self->emit('finish')->recurring(1 => \&_stop);
 }
 
 sub stream {
@@ -311,6 +311,20 @@ C<MOJO_NO_TLS> environment variables.
 
 See L<Mojolicious::Guides::Cookbook/"REAL-TIME WEB"> for more.
 
+=head1 EVENTS
+
+L<Mojo::IOLoop> inherits all events from L<Mojo::EventEmitter> and can emit
+the following new ones.
+
+=head2 finish
+
+  $loop->on(finish => sub {
+    my $loop = shift;
+    ...
+  });
+
+Emitted when the event loop shuts down gracefully.
+
 =head1 ATTRIBUTES
 
 L<Mojo::IOLoop> implements the following attributes.
@@ -366,8 +380,8 @@ L<Mojo::Reactor/"error">.
 
 =head1 METHODS
 
-L<Mojo::IOLoop> inherits all methods from L<Mojo::Base> and implements the
-following new ones.
+L<Mojo::IOLoop> inherits all methods from L<Mojo::EventEmitter> and implements
+the following new ones.
 
 =head2 acceptor
 

diff --git a/lib/Mojo/Server/Prefork.pm b/lib/Mojo/Server/Prefork.pm
@@ -154,8 +154,10 @@ sub _spawn {
 
   # Heartbeat messages
   weaken $self;
-  my $cb = sub { $self->_heartbeat(shift->max_connections ? 0 : 1) };
-  my $loop = $self->ioloop;
+  my $loop     = $self->ioloop;
+  my $finished = 0;
+  $loop->on(finish => sub { $finished = 1 });
+  my $cb = sub { $self->_heartbeat($finished) };
   $loop->next_tick($cb);
   $loop->recurring($self->heartbeat_interval => $cb);
 

diff --git a/lib/Mojolicious/Guides.pod b/lib/Mojolicious/Guides.pod
@@ -227,6 +227,8 @@ This is the class hierarchy of the L<Mojolicious> distribution.
 
 =back
 
+=item * L<Mojo::IOLoop>
+
 =item * L<Mojo::IOLoop::Client>
 
 =item * L<Mojo::IOLoop::Delay>
@@ -301,8 +303,6 @@ This is the class hierarchy of the L<Mojolicious> distribution.
 
 =item * L<Mojo::Home>
 
-=item * L<Mojo::IOLoop>
-
 =item * L<Mojo::JSON::Pointer>
 
 =item * L<Mojo::Loader>

diff --git a/t/mojo/ioloop.t b/t/mojo/ioloop.t
@@ -260,12 +260,15 @@ is $client, 'works!', 'full message has been written';
 # Graceful shutdown
 $err  = '';
 $loop = Mojo::IOLoop->new;
+my $finish;
+$loop->on(finish => sub { $finish++ });
 $loop->stop_gracefully;
 $loop->remove(
   $loop->client({port => Mojo::IOLoop::Server->generate_port} => sub { }));
 $loop->timer(3 => sub { shift->stop; $err = 'failed' });
 $loop->start;
 ok !$err, 'no error';
+is $finish, 1, 'finish event has been emitted once';
 
 # Graceful shutdown (max_accepts)
 $err  = '';