Ability to export existing models as sync files

src/Console/Commands/Export.php

@@ -0,0 +1,24 @@
+<?php
+
+namespace nullthoughts\LaravelDataSync\Console\Commands;
+
+use nullthoughts\LaravelDataSync\Exporter;
+use Illuminate\Console\Command;
+
+class Export extends Command
+{
+    protected $signature = 'data:export {model} {--criteria=*} {--except=*} {--only=*}';
+
+    protected $description = 'Export Model data for synchronization';
+
+    public function handle()
+    {
+        $model = $this->argument('model');
+
+        $this->info('Exporting ' . $model . ' model to sync data file');
+
+        (new Exporter($model, $this->option('criteria'), $this->option('except'), $this->option('only')))->run();
+
+        $this->comment('Export for data sync completed');
+    }
+}

src/DataSyncBaseServiceProvider.php

@@ -17,6 +17,7 @@ class DataSyncBaseServiceProvider extends ServiceProvider
     {
         $this->commands([
             Console\Commands\Sync::class,
+            Console\Commands\Export::class,
         ]);
     }
 

src/Exporter.php

@@ -0,0 +1,96 @@
+<?php
+
+namespace nullthoughts\LaravelDataSync;
+
+use Illuminate\Support\Facades\Schema;
+use Illuminate\Support\Facades\Storage;
+use nullthoughts\LaravelDataSync\Exceptions\FileDirectoryNotFoundException;
+
+class Exporter
+{
+    private $modelName;
+
+    private $criteria;
+
+    private $except;
+
+    private $only;
+
+    /**
+     * Get files in sync directory.
+     *
+     * @param  string  $model
+     * @param  array  $criteria
+     *
+     * @throws \nullthoughts\LaravelDataSync\Exceptions\FileDirectoryNotFoundException
+     */
+    public function __construct(string $modelName, array $criteria = [], $except = [], $only = [])
+    {
+        $this->modelName = $modelName;
+        $this->criteria = $criteria;
+        $this->except = $except;
+        $this->only = $only;
+    }
+
+    /**
+     * Export Model data to sync file.
+     *
+     * @return mixed
+     */
+    public function run()
+    {
+        $class = config('data-sync.namespace', '\\App\\Models\\') . $this->modelName;
+        $filename = $this->getDirectory() . '/' . $this->modelName . '.json';
+        $data = $this->prepareData($class);
+
+        file_put_contents($filename, $data);
+    }
+
+    /**
+     * Get directory path for sync files.
+     *
+     * @throws \nullthoughts\LaravelDataSync\Exceptions\FileDirectoryNotFoundException
+     *
+     * @return string
+     */
+    protected function getDirectory()
+    {
+        $directory = config('data-sync.path', base_path('sync'));
+
+        if (! file_exists($directory)) {
+            throw new FileDirectoryNotFoundException();
+        }
+
+        return $directory;
+    }
+
+    protected function prepareData($class)
+    {
+        $class = new $class;
+        $keys = $this->prepareKeys($class);
+
+        return $class->select($keys)->get()->toJson();
+    }
+
+    protected function prepareKeys($class)
+    {
+        $keys = Schema::getColumnListing($class->getTable());
+
+        if ($this->only) {
+            $keys = array_intersect($keys, $this->only);
+        }
+
+        if ($this->except) {
+            $keys = array_diff($keys, $this->except);
+        }
+        
+
+        return collect($keys)->map(function ($key) {
+            if (in_array($key, $this->criteria)) {
+                return $key . ' as _' . $key;
+            }
+
+            return $key;
+        })->toArray();
+    }
+}