Merge pull request #7 from barryosull/feature/player_versioning

Added player versioning.

src/Contracts/Player/Factory.php

@@ -12,5 +12,10 @@ interface Factory
      */
     public function snapshot(Snapshot $snapshot);
 
+    /**
+     * Returns a Player by a Classname.
+     *
+     * @return Player $player
+     */
     public function make($class_name);
 }

src/Contracts/Player/Player.php

@@ -13,4 +13,9 @@ interface Player extends Resetable, Playable
      */
 
     public function snapshot();
+
+    /**
+     * @return int
+     */
+    public function version();
 }

src/Contracts/Player/Repository.php

@@ -15,4 +15,6 @@ public function get(ClassName $class_name);
      * @return void
      */
     public function save(Player $player);
+
+    public function hasVersionChanged(ClassName $class_name);
 }

src/Contracts/Player/Snapshot/Snapshot.php

@@ -4,6 +4,7 @@
 use EventSourced\ValueObject\Contracts\ValueObject\Identifier;
 use BoundedContext\Contracts\Generator\DateTime as DateTimeGenerator;
 use BoundedContext\Contracts\Generator\Identifier as IdentifierGenerator;
+use EventSourced\ValueObject\ValueObject\Integer as Integer_;
 
 interface Snapshot extends \BoundedContext\Contracts\Snapshot\Snapshot
 {
@@ -20,6 +21,11 @@ public function class_name();
 
     public function last_id();
 
+    /**
+     * @return Integer_
+     */
+    public function updateCount();
+
     /**
      * Returns a new Snapshot after resetting it back to its default state.
      *
@@ -28,10 +34,10 @@ public function last_id();
      *
      * @return Snapshot
      */
-
     public function reset(
         IdentifierGenerator $identifier_generator,
-        DateTimeGenerator $datetime_generator
+        DateTimeGenerator $datetime_generator,
+        Integer_ $version
     );
 
     /**

src/Player/AbstractPlayer.php

@@ -34,12 +34,17 @@ public function reset()
     {
         $this->snapshot = $this->snapshot->reset(
             $this->identifier_generator,
-            $this->datetime_generator
+            $this->datetime_generator,
+            new Integer($this->version())
         );
     }
 
     public function play($limit = 1000)
     {
+        if ($this->snapshot()->version()->value() != $this->version()) {
+            throw new \Exception("The snapshot and projector have different versions, playing would cause potential data corruption. This exception only occurs if the players are used incorrectly.");
+        }
+
         $snapshot_stream = $this->log
             ->builder()
             ->after($this->snapshot()->last_id())
@@ -74,4 +79,24 @@ public function snapshot()
     {
         return $this->snapshot;
     }
+
+    /**
+     * @return int
+     */
+    public function version()
+    {
+        $player_class = get_called_class();
+
+        $path = explode("\\", $player_class);
+
+        $path[count($path)-1] = "Version";
+
+        $version_class = implode("\\", $path);
+
+        if (!class_exists($version_class)) {
+            return 1;
+        }
+
+        return $version_class::VALUE;
+    }
 }

src/Player/Collection/Player.php

@@ -39,4 +39,14 @@ public function snapshot()
     {
         throw new \Exception("Collection Player Snapshots are not supported.");
     }
+
+    public function version()
+    {
+        throw new \Exception("Collection Player versions are not supported.");
+    }
+
+    public function count()
+    {
+        return $this->player_classes->count()->value();
+    }
 }

src/Player/Repository.php

@@ -4,6 +4,7 @@
 use BoundedContext\Contracts\Player\Snapshot\Repository as SnapshotRepository;
 use BoundedContext\Contracts\Player\Factory as PlayerFactory;
 use BoundedContext\Player\Snapshot\ClassName;
+use EventSourced\ValueObject\ValueObject\Integer as Integer_;
 
 class Repository implements \BoundedContext\Contracts\Player\Repository
 {
@@ -35,4 +36,18 @@ public function save(Player $player)
     {
         $this->snapshot_repository->save($player->snapshot());
     }
+
+    public function hasVersionChanged(ClassName $class_name)
+    {
+        $snapshot = $this->snapshot_repository->get($class_name);
+
+        $active_version = new Integer_(1);
+        if ($snapshot) {
+            $active_version = $snapshot->version();
+        }
+
+        $player = $this->player_factory->make($class_name);
+
+        return $active_version->value() != $player->version();
+    }
 }

src/Player/Snapshot/Factory.php

@@ -23,6 +23,7 @@ public function make(array $snapshot)
         return new Snapshot(
             new ClassName($snapshot['class_name']),
             new Integer($snapshot['version']),
+            new Integer($snapshot['update_count']),
             $this->datetime_generator->string($snapshot['occurred_at']),
             $this->identifier_generator->string($snapshot['last_id'])
         );

src/Player/Snapshot/Snapshot.php

@@ -5,22 +5,25 @@
 use BoundedContext\Contracts\Generator\DateTime as DateTimeGenerator;
 use BoundedContext\Contracts\Generator\Identifier as IdentifierGenerator;
 use BoundedContext\Snapshot\AbstractSnapshot;
-use EventSourced\ValueObject\ValueObject\Integer as Version;
+use EventSourced\ValueObject\ValueObject\Integer as Integer_;
 
 class Snapshot extends AbstractSnapshot implements \BoundedContext\Contracts\Player\Snapshot\Snapshot
 {
     public $last_id;
-    private $class_name;
+    protected $class_name;
+    protected $update_count;
 
     public function __construct(
         ClassName $class_name,
-        Version $version,
+        Integer_ $version,
+        Integer_ $update_count,
         DateTime $occurred_at,
         Identifier $last_id
     )
     {
         parent::__construct($version, $occurred_at);
         $this->class_name = $class_name;
+        $this->update_count = $update_count;
         $this->last_id = $last_id;
     }
 
@@ -31,12 +34,14 @@ public function last_id()
 
     public function reset(
         IdentifierGenerator $identifier_generator,
-        DateTimeGenerator $datetime_generator
+        DateTimeGenerator $datetime_generator,
+        Integer_ $version
     )
     {
         return new Snapshot(
             $this->class_name,
-            $this->version->reset(),
+            $version,
+            $this->update_count->reset(),
             $datetime_generator->now(),
             $identifier_generator->null()
         );
@@ -50,6 +55,7 @@ public function skip(
         return new Snapshot(
             $this->class_name,
             $this->version,
+            $this->update_count,
             $datetime_generator->now(),
             $next_id
         );
@@ -62,7 +68,8 @@ public function take(
     {
         return new Snapshot(
             $this->class_name,
-            $this->version->increment(),
+            $this->version,
+            $this->update_count->increment(),
             $datetime_generator->now(),
             $next_id
         );
@@ -81,9 +88,15 @@ public static function make(
     {
         return new Snapshot(
             $class_name,
-            new Version(1),
+            new Integer_(1),
+            new Integer_(1),
             $datetime_generator->now(),
             $identifier_generator->null()
         );
     }
+
+    public function updateCount()
+    {
+        return $this->update_count;
+    }
 }

src/Snapshot/AbstractSnapshot.php

@@ -2,15 +2,15 @@
 
 use EventSourced\ValueObject\Contracts\ValueObject\DateTime;
 use EventSourced\ValueObject\ValueObject\Type\AbstractComposite;
-use EventSourced\ValueObject\ValueObject\Integer as Version;
+use EventSourced\ValueObject\ValueObject\Integer as Integer_;
 
 abstract class AbstractSnapshot extends AbstractComposite
 {
     protected $version;
     protected $occurred_at;
 
     public function __construct(
-        Version $version,
+        Integer_ $version,
         DateTime $occurred_at
     )
     {