Laravel optional parameter in API-request perceived incorrectly

Question

In my api.php I've these routes.

I can request endpoint: /api/v2/commodities/1 - this request is being redirected to APICommodityController@read - this is OK!

The problem occur whenever I GET-request /v2/commodities/categories/. I'd like this request to be redirected into the route-group: 'categories', but instead Laravel perceive this as a optional parameter within the first group (~ ref. "HERE" in code-comment).

How do I fix this?

Route::group( [ 'prefix' => 'v2' ], function() {

    /**
     * Commodity
     */
    Route::group( [ 'prefix' => 'commodities' ], function() {

        /**
         * C: CREATE
         */
        Route::post( '{id?}', 'API\v2\Commodity\APICommodityController@updateOrCreate' );

        /**
         * U: UPDATE
         */
        Route::put( '{id}', 'API\v2\Commodity\APICommodityController@updateOrCreate' );

        /**
         * R: READ (HERE)
         */
        Route::get( '{id?}', 'API\v2\Commodity\APICommodityController@read' );

        /**
         * D: DELETE
         */
        Route::delete( '{id}', 'API\v2\Commodity\APICommodityController@delete' );

        /**
         * Commodity categories
         */
        Route::group( [ 'prefix' => 'categories' ], function() {

            /**
             * C: CREATE
             */
            Route::post( '{id?}', 'API\v2\CommodityCategories\APICommodityCategoriesController@updateOrCreate' );

            /**
             * U: UPDATE
             */
            Route::put( '{id}', 'API\v2\CommodityCategories\APICommodityCategoriesController@updateOrCreate' );

            /**
             * R: READ
             */
            Route::get( '{id?}', 'API\v2\CommodityCategories\APICommodityCategoriesController@read' );

            /**
             * D: DELETE
             */
            Route::delete( '{id}', 'API\v2\CommodityCategories\APICommodityCategoriesController@delete' );

        } );

    } );

Answer 1

add this condition at the end of your id parameters :

->where('id', '[0-9]+')

so it becomes something like this :

Route::get( '{id?}', 'API\v2\Commodity\APICommodityController@read' )->where('id', '[0-9]+');