add ping pong

javascript sample(in connection.js)
```
_ping('ping', 'your_nice_token')
```
this code will send ping event with token.

yancha will sendback pong event with token.

lib/Yancha/Core.pm

@@ -40,6 +40,7 @@ sub dispatch {
         $socket->on( 'join tag'     => sub { $self->join_tag( @_ ); } );
         $socket->on( 'disconnect'   => sub { $self->disconnect( @_ ); } );
         $socket->on( 'fukumotosan'  => sub { $self->fukumotosan( @_ ); } );
+        $socket->on( 'ping'         => sub { $self->ping( @_ ); } );
         $socket->on( 'delete user message'   => sub { $self->delete_user_message( @_ ); } );
         $self->sys->call_hook( 'connected', $socket, $env );
     };
@@ -181,6 +182,21 @@ sub plusplus {
     $self->sys->send_post_to_tag_joined( $post => $post->{ tags } );
 }
 
+sub ping {
+    my ( $self, $socket, $token ) = @_;
+
+    $socket->get('user_data' => sub {
+        my ($socket, $err, $user) = @_;
+
+        if(!defined($user)){
+            $socket->emit('no session');
+            return;
+        }
+
+        $socket->emit('pong', $token);
+    });
+}
+
 sub fukumotosan {
     my ( $self, $socket ) = @_;
 

static/js/connection.js

@@ -41,6 +41,14 @@ socket.on('announcement', function (msg) {
   announcement(msg)
 });
 
+//ping pong
+socket.on('pong', function (msg) {
+  console.log(msg);
+});
+function _ping(token){
+  socket.emit('ping', token);
+  console.log("sent ping :"+token);
+}
 
 //サーバから、参加ニックネームリストの更新
 socket.on('nicknames', function (nicknames) {

t/504_pingpong.t

@@ -0,0 +1,83 @@
+use strict;
+use warnings;
+use PocketIO::Test;
+use t::Utils;
+use AnyEvent;
+use Yancha;
+use Yancha::Client;
+use Yancha::DataStorage::DBI;
+use Plack::Builder;
+
+BEGIN {
+    use Test::More;
+    plan skip_all => 'PocketIO::Client::IO are required to run this test'
+      unless eval { require PocketIO::Client::IO; 1 };
+}
+
+my $testdb = t::Utils->setup_testdb( schema => './db/init.sql' );
+my $config = {
+    'database' => { connect_info => [ $testdb->dsn ] },
+    'server_info' => {
+        default_tag   => 'PUBLIC',
+        auth_endpoint => {
+            '/login' => [ 'Yancha::Auth::Simple'  => { name_field => 'nick' } => {} ],
+        }
+    },
+
+    'plugins' => [
+        [ 'Yancha::Plugin::NoRec' ],
+    ],
+};
+my $data_storage = Yancha::DataStorage::DBI->connect(
+                            connect_info => $config->{ database }->{ connect_info } );
+
+my $sys = Yancha->new( config => $config, data_storage => $data_storage );
+my $server = builder {
+    enable 'Session';
+    $sys->build_psgi_endpoint_from_server_info('auth');
+    mount '/socket.io' => PocketIO->new(
+            socketio => $config->{ socketio },
+            instance => $sys,
+    );
+};
+
+my $client = sub {
+    my ( $port ) = shift;
+
+    my $cv = AnyEvent->condvar;
+    my $w  = AnyEvent->timer( after => 10, cb => sub {
+        fail("Time out.");
+        $cv->send;
+    } );
+
+    my $on_connect = sub {
+        my ( $client ) = @_;
+        my $count = 0;
+
+        $client->socket->on('pong' => sub {
+            my $post = $_[1];
+
+            is( $post, 'my_uuid' );
+
+            $cv->send;
+        });
+
+    };
+
+    my ( $client ) = t::Utils->create_clients_and_set_tags(
+        $port,
+        { nickname => 'user', on_connect => $on_connect },
+    );
+
+    $client->socket->emit('ping', "my_uuid");
+
+
+    $cv->wait;
+};
+
+test_pocketio $server, $client;
+
+ok(1, 'test done');
+
+done_testing;
+