Added multichannels and a simple channel-based bus

README.md

@@ -155,3 +155,34 @@ or through the `createPair()` factory method.
     [ $ch1, $ch2 ] = StreamChannel::createPair();
     $ch1->send($data);
     $rcvd = $ch2->receive();
+
+### MultiChannels
+
+The `MultiStreamChannel` lets you connect multiple clients to a single master channel.
+
+    $master = new MultiStreamChannel();
+
+    $ch1 = $master->createClient();
+    $ch2 = $master->createClient();
+    $ch1->send($data);
+    $rcvd = $ch2->receive();
+
+### Buses
+
+Buses are high-level abstractions of channels, implementing limited rpc with handling of
+return values.
+
+    $master = new Master();
+
+    $client = $master->createClient();
+    $client->export("/db/updateindex", function ($schema) {
+        // Update the index
+        return true;
+    });
+
+    $other = $master->createClient();
+    $other->call("/db/updateindex", "*")->then(function ($status) {
+        if ($status === true) {
+            echo "Index updated!\n";
+        }
+    });

examples/bus.php

@@ -0,0 +1,28 @@
+<?php
+
+require_once __DIR__."/../vendor/autoload.php";
+
+use NoccyLabs\Ipc\Interop\Bus\Master;
+
+
+$master = new Master();
+
+$client1 = $master->createClient();
+$client1->addListener(function ($msg) use ($client1) {
+    printf("channel1: %s\n", json_encode($msg));
+    $client1->call("/channel2/hello", "channel1")->then(function ($ret) {
+        printf("channel1: %s\n", $ret);
+    });
+});
+$client2 = $master->createClient();
+$client2->addListener(function ($msg) {
+    printf("channel2: %s\n", json_encode($msg));
+});
+$client2->export("/channel2/hello", function ($name) {
+    return sprintf("Hello, %s", $name);
+});
+
+$client1->send("hello world");
+for ($n = 0; $n < 10; $n++) {
+    sleep(1);
+}

src/Interop/Async/Promise.php

@@ -0,0 +1,20 @@
+<?php
+
+namespace NoccyLabs\Ipc\Interop\Async;
+
+
+class Promise
+{
+    private $then;
+
+    public function then(callable $then)
+    {
+        $this->then = $then;
+    }
+
+    public function invoke(...$args)
+    {
+        call_user_func($this->then, ...$args);
+    }
+    
+}

src/Interop/Async/Timer.php

@@ -23,7 +23,6 @@ class Timer
     public function __construct(callable $callback)
     {
         $this->callback = $callback;
-        $this->seconds = $seconds;
         self::registerTimer($this->callback);
     }
 

src/Interop/Bus/Client.php

@@ -0,0 +1,104 @@
+<?php
+
+namespace NoccyLabs\Ipc\Interop\Bus;
+
+use NoccyLabs\Ipc\Interop\Channel\ChannelInterface;
+use NoccyLabs\Ipc\Interop\Channel\MultiStreamChannel;
+use NoccyLabs\Ipc\Interop\Async\Timer;
+use NoccyLabs\Ipc\Interop\Async\Promise;
+
+class Client
+{
+    /** @var ChannelInterface $channel */
+    protected $channel;
+
+    protected $listeners = [];
+
+    protected $promises = [];
+
+    protected $exports = [];
+
+    /**
+     * Constructor
+     */
+    public function __construct(ChannelInterface $channel)
+    {
+        $this->channel = $channel;
+        $this->timer = new Timer([ $this, "update" ]);
+    }
+
+    public function update()
+    {
+        while ($msg = $this->channel->receive()) {
+            if (!array_key_exists('op', $msg)) {
+                fprintf(STDERR, "Warning: Frame missing op -- %s\n", json_encode($msg));
+                continue;
+            }
+            switch ($msg['op']) {
+                case 'retn':
+                    $id = $msg['id'];
+                    if (!array_key_exists($id, $this->promises)) {
+                        continue;
+                    }
+                    $promise = $this->promises[$id];
+                    $promise->invoke($msg['ret']);
+                    unset($this->promises[$id]);
+                    continue;
+                case 'call':
+                    $id = $msg['id'];
+                    $obj = $msg['obj'];
+                    if (!array_key_exists($obj, $this->exports)) {
+                        continue;
+                    }
+                    $ret = call_user_func($this->exports[$obj], ...$msg['arg']);
+                    $frame = [
+                        'op' => 'retn',
+                        'id' => $id,
+                        'ret' => $ret
+                    ];
+                    $this->channel->send($frame);
+                    continue;
+                case 'msg':
+                default:
+                    foreach ($this->listeners as $listener) {
+                        call_user_func($listener, $msg);
+                    }
+            }
+        }
+    }
+
+    public function addListener(callable $handler)
+    {
+        $this->listeners[] = $handler;
+    }
+
+    public function export($path, callable $function)
+    {
+        $this->exports[$path] = $function;
+    }
+
+    public function send($data)
+    {
+        $frame = [
+            'op' => 'msg',
+            'msg' => $data
+        ];
+        $this->channel->send($frame);
+    }
+
+    public function call($path, ...$args)
+    {
+        $promise = new Promise();
+
+        $rid = uniqid(md5($path),true);
+        $frame = [
+            'op' => 'call',
+            'id' => $rid,
+            'obj' => $path,
+            'arg' => $args,
+        ];
+        $this->promises[$rid] = $promise;
+        $this->channel->send($frame);
+        return $promise;
+    }
+}

src/Interop/Bus/Master.php

@@ -0,0 +1,40 @@
+<?php
+
+namespace NoccyLabs\Ipc\Interop\Bus;
+
+use NoccyLabs\Ipc\Interop\Channel\ChannelInterface;
+use NoccyLabs\Ipc\Interop\Channel\MultiStreamChannel;
+use NoccyLabs\Ipc\Interop\Async\Timer;
+
+class Master
+{
+    /** @var ChannelInterface $channel */
+    protected $channel;
+
+    /**
+     * Constructor
+     */
+    public function __construct()
+    {
+        $this->channel = new MultiStreamChannel();
+
+        $this->timer = new Timer([ $this, "update" ]);
+    }
+
+    public function createClient() : Client
+    {
+        /** @var ChannelInterface $channel */
+        $channel = $this->channel->createClient();
+
+        $client = new Client($channel);
+        return $client;
+    }
+
+    public function update()
+    {
+        while ($msg = $this->channel->receive()) {
+            $this->channel->send($msg);
+        }
+    }
+
+}

src/Interop/Channel/ChannelInterface.php

@@ -20,10 +20,10 @@ interface ChannelInterface
     public function receive();
 
     /**
-     * Send a frame of data
+     * Send a frame of data, returns true on success
      *
      * @param mixed $data
-     * @return void
+     * @return bool
      */
-    public function send($data);
+    public function send($data):bool;
 }

src/Interop/Channel/MultiStreamChannel.php

@@ -40,13 +40,16 @@ class MultiStreamChannel implements ChannelInterface
      * {@inheritDoc}
      *
      * @param mixed $data
-     * @return void
+     * @return bool
      */
-    public function send($data)
+    public function send($data):bool
     {
-        foreach ($this->clients as $client) {
-            $client->send($data);
+        foreach ($this->clients as $i=>$client) {
+            if (false === $client->send($data)) {
+                unset($this->clients[$i]);
+            }
         }
+        return true;
     }
 
     /**

src/Interop/Channel/StreamChannel.php

@@ -36,11 +36,16 @@ class StreamChannel implements ChannelInterface
      * {@inheritDoc}
      *
      * @param mixed $data
-     * @return void
+     * @return bool
      */
-    public function send($data)
+    public function send($data):bool
     {
-        fwrite($this->stream, json_encode($data)."\0");
+        $json = json_encode($data) . "\0";
+        $ret = @fwrite($this->stream, $json, strlen($json));
+        if (false === $ret) {
+            return false;
+        }
+        return true;
     }
 
     /**