add json support

README.md

@@ -69,6 +69,93 @@ All timestamps and the optional soft-delete timestamp will be ignored.
 
 <a name="exclude" />
 
+### Using JSON encoding
+
+Run
+
+```
+php artisan vendor:publish --provider="Mpociot\Versionable\Providers\ServiceProvider" --tag="config"
+```
+
+Adjust the encoding in the config from `serialize` to `json`.
+
+Create and run a migration like the following:
+
+```
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Mpociot\Versionable\Version;
+
+class Encoding extends Migration
+{
+    protected $encodingCheck = [
+        'serialize' => '{',
+        'json' => 'a:',
+    ];
+
+    protected $chunkSize = 10;
+
+    /**
+     * Run the migrations.
+     *
+     * @return void
+     */
+    public function up()
+    {
+        $targetEncoding = config('versionable.encoding');
+        $sourceEncoding = $targetEncoding === 'json' ? 'serialize' : 'json';
+
+        $this->changeEncoding($targetEncoding, $sourceEncoding);
+
+        Schema::table('versions', function ($table) {
+            $table->json('model_data')->change();
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     *
+     * @return void
+     */
+    public function down()
+    {
+        $sourceEncoding = config('versionable.encoding');
+        $targetEncoding = $sourceEncoding === 'json' ? 'serialize' : 'json';
+
+        $this->changeEncoding($targetEncoding, $sourceEncoding);
+
+        Schema::table('versions', function ($table) {
+            $table->longText('model_data')->change();
+        });
+    }
+
+    protected function changeEncoding($targetEncoding, $sourceEncoding)
+    {
+        $versions = Version::lazy($this->chunkSize);
+
+        foreach ($versions as $version) {
+            $this->validateData($version, $sourceEncoding);
+
+            $version->model_data = $targetEncoding === 'serialize'
+                ? serialize(json_decode($version->model_data, true))
+                : json_encode(unserialize($version->model_data));
+
+            $version->save();
+        }
+
+        return true;
+    }
+
+    protected function validateData(Version $version, $sourceEncoding)
+    {
+        if (strpos($version->model_data, $this->encodingCheck[$sourceEncoding]) === 0) {
+            throw new RuntimeException("Wrong source encoding while trying to convert from '$sourceEncoding': ".substr($version->model_data, 0, 10).'..');
+        }
+    }
+}
+```
+
 ### Exclude attributes from versioning
 
 Sometimes you don't want to create a version *every* time an attribute on your model changes. For example your User model might have a `last_login_at` attribute. 

src/Mpociot/Versionable/Version.php

@@ -31,6 +31,15 @@ public function versionable()
         return $this->morphTo();
     }
 
+    /**
+     * Return the encoding
+     * @return mixed
+     */
+    private function getEncoding()
+    {
+        return config('versionable.encoding', 'serialize');
+    }
+
     /**
      * Return the user responsible for this version
      * @return mixed
@@ -50,10 +59,11 @@ public function getModel()
         $modelData = is_resource($this->model_data)
             ? stream_get_contents($this->model_data,-1,0)
             : $this->model_data;
+        $modelDataEncoded = $this->getEncoding() === 'json' ? json_decode($modelData, true) : unserialize($modelData);
 
         $model = new $this->versionable_type();
         $model->unguard();
-        $model->fill(unserialize($modelData));
+        $model->fill($modelDataEncoded);
         $model->exists = true;
         $model->reguard();
         return $model;

src/Mpociot/Versionable/VersionableTrait.php

@@ -14,7 +14,7 @@ trait VersionableTrait
     /**
      * Retrieve, if exists, the property that define that Version model.
      * If no property defined, use the default Version model.
-     * 
+     *
      * Trait cannot share properties whth their class !
      * http://php.net/manual/en/language.oop5.traits.php
      * @return unknown|string
@@ -28,6 +28,16 @@ protected function getVersionClass()
         return config('versionable.version_model', Version::class);
     }
 
+    /**
+     * Get the encoding, the default is serialize.
+     *
+     * @return string
+     */
+    protected function getEncoding()
+    {
+        return config('versionable.encoding', 'serialize');
+    }
+
     /**
      * Private variable to detect if this is an update
      * or an insert
@@ -173,10 +183,12 @@ protected function versionablePostSave()
             $version->versionable_id   = $this->getKey();
             $version->versionable_type = method_exists($this, 'getMorphClass') ? $this->getMorphClass() : get_class($this);
             $version->user_id          = $this->getAuthUserId();
-            
+
             $versionedHiddenFields = $this->versionedHiddenFields ?? [];
             $this->makeVisible($versionedHiddenFields);
-            $version->model_data       = serialize($this->attributesToArray());
+            $version->model_data = $this->getEncoding() === 'json'
+                ? json_encode($this->attributesToArray())
+                : serialize($this->attributesToArray());
             $this->makeHidden($versionedHiddenFields);
 
             if (!empty( $this->reason )) {
@@ -191,16 +203,16 @@ protected function versionablePostSave()
 
     /**
      * Delete old versions of this model when the reach a specific count.
-     * 
+     *
      * @return void
      */
     private function purgeOldVersions()
     {
         $keep = isset($this->keepOldVersions) ? $this->keepOldVersions : 0;
-        
+
         if ((int)$keep > 0) {
             $count = $this->versions()->count();
-            
+
             if ($count > $keep) {
                 $this->getLatestVersions()
                     ->take($count)

src/config/config.php

@@ -7,6 +7,11 @@
      * Feel free to change this, if you need specific version
      * model logic.
      */
-    'version_model' => \Mpociot\Versionable\Version::class
+    'version_model' => \Mpociot\Versionable\Version::class,
 
-];
+    /*
+     * The encoding to use for the model data encoding.
+     * Default is 'serialize' and uses PHP serialize() but 'json' is also supported
+     */
+    'encoding' => 'serialize',
+];

tests/VersionableTest.php

@@ -460,19 +460,19 @@ public function testKeepMaxVersionCount()
         $name_v2 = 'second' ;
         $name_v3 = 'third' ;
         $name_v4 = 'fourth' ;
-        
+
         $model = new ModelWithMaxVersions();
         $model->email = "[email protected]";
         $model->password = "foo";
         $model->name = $name_v1 ;
         $model->save();
-        
+
         $model->name = $name_v2 ;
         $model->save();
-        
+
         $model->name = $name_v3 ;
         $model->save();
-        
+
         $model->name = $name_v4 ;
         $model->save();
 
@@ -513,7 +513,24 @@ public function testAllowHiddenFields() {
 
         $this->assertArrayNotHasKey('password', $user->toArray());
     }
-
+
+    public function testVersionWithJson()
+    {
+        $this->app['config']->set('versionable.encoding', 'json');
+
+        $user = new TestVersionableUser();
+        $user->name = "Marcel";
+        $user->email = "[email protected]";
+        $user->password = "12345";
+        $user->last_login = $user->freshTimestamp();
+        $user->save();
+
+        $version = $user->currentVersion();
+
+        $this->assertStringStartsWith( '{', $version->model_data, 'Model data is not json encoded' );
+        $this->assertEquals( $user->attributesToArray(), $version->getModel()->attributesToArray() );
+    }
+
 }