complete the model, controller, and migration

app/So.php

@@ -7,7 +7,6 @@ use Illuminate\Database\Eloquent\Model;
 class So extends Model
 {
      protected $fillable = [
-        'id',
         'ff_id',
         'supplier_company_name',
         'supplier_contact_person',
@@ -16,4 +15,9 @@ class So extends Model
         'warehouse_id',
     ];
 
+    public function Soitem()
+    {
+        return $this->hasMany(Soitem::class);
+    }
+
 }

app/Soitem.php

@@ -7,7 +7,8 @@ use Illuminate\Database\Eloquent\Model;
 class Soitem extends Model
 {
      protected $fillable = [
-        'id',
+        'so_id',
+        'status',
         'order_id',
         'brand_no',
         'model_no',
@@ -24,4 +25,10 @@ class Soitem extends Model
 
     ];
 
+     public function So()
+    {
+        return $this->belongsTo(So::class);
+    }
+
+
 }

database/migrations/2018_05_15_034032_create_soitems_table.php

@@ -16,6 +16,14 @@ class CreateSoitemsTable extends Migration
         Schema::create('soitems', function (Blueprint $table) {
             $table->increments('id');
 
+            // foreign key for the so table
+            $table->unsignedInteger('so_id');
+            $table->foreign('so_id')
+               ->references('id')->on('sos')
+               ->onDelete('cascade')
+               ->onUpdate('cascade');
+            $table->Integer('status')->default('0');
+
             //Item details
             $table->integer('order_id');
             $table->integer('brand_no');

routes/api.php

@@ -16,7 +16,7 @@ use Illuminate\Http\Request;
 //Route for the shipping order
 Route::get('/so', 'SoController@index');// get the list of the shipping order 
 Route::get('/so/{so_id}', 'SoController@so');//get the shipping order 
-Route::post('/so/{so_id}', 'SoController@store');//create shipping order 
+Route::post('/so/{so_id}', 'SoController@store');//store shipping order 
 Route::post('/so/{so_id}/cancel-order', 'SoController@cancelorder');//post the cancel order 
 Route::delete('/so/{so_id}', 'SoController@delete');// delete the shipping order
 Route::put('/so/{so_id}', 'SoController@update');//update the shipping order