Laravel 5: Trying to get property of non-object through method injection - php

Question

I am using Route-Model-Binding with method injection to retrieve the $post->id of the post I am commenting on, but I keep getting this error
Trying to get property of non-object (View: C:\xampp\htdocs\reddit\resources\views\partials\post.blade.php) (View: C:\xampp\htdocs\reddit\resources\views\partials\post.blade.php)
This is the method I have, injecting Post $post then trying to get $post->id
dd($post) retrieves nothing at all even if I dump the model alone.
public function post_this_comment(Request $request, Post $post) {
$post = Post::whereId($post->id)->first(); // this is where I'm getting the post
$comment = new Comment;
$comment->user_id = Auth::id();
$comment->comment = $request->input('commenter_comment');
$comment->parent_id = $request->input('commenter_parent');
if($comment->parent_id > 0){
$my_parent = Comment::find($comment->parent_id);
$comment->parents = $my_parent->parents.'.'.$comment->parent_id;
}else{
$comment->parents = '0';
}
$comment->save();
$per_page = $request->input('per_page');
$comment_list = view('post/show')
->with('comments', $this->comment_list($per_page, $request))
->with('total_comments', $this->total_comments())
->with('per_page', $per_page)
->with('post', $post)
->render();
$response = array(
'status' => 'success',
'msg' => 'Comment Saved!',
'comment_list' => $comment_list
);
return Response::json($response);
}
This is the view, I have opened a form even though I don't need it because I'm submitting data via ajax.
{!! Form::open(['route' => ['post_this_comment', $post]]) !!}
<div class="comment-fields">
<div class="commenter-comment">
<div class="form-group col-md-12">
<textarea id="commenter_comment" name="commenter_comment" class="form-control comment-field" title="User's comment" placeholder="Comment Text"></textarea>
</div>
</div>
<div class="commenter-name-email">
<input type="hidden" id="commenter_parent" name="commenter_parent" class="commenter-parent" value="0">
</div>
<div class="commenter-captcha">
<div class="col-md-3 text-right">
Comment
</div>
</div>
{!! Form::close() !!}
Routes
Route::resource('posts', 'PostsController');
Route::post('{post}/post_this_comment', ['as' => 'post_this_comment', 'uses' => 'PostsController#post_this_comment']);
RouteServiceProvider
$router->model('articles', 'App\Article');
$router->model('subreddit', 'App\Subreddit');
$router->model('posts', 'App\Post');
$router->model('moderators', 'App\Moderator');
$router->model('comments', 'App\Comment');

Answer 1

The parameter in your route needs to match the one you used for your route model binding. In your case you have defined posts: $router->model('posts', 'App\Post'); but you are using {post} (without the 's') as the parameter in your route. Instead your route should be:
Route::post('{posts}/post_this_comment', ['as' => 'post_this_comment', 'uses' => 'PostsController#post_this_comment']);
If you want to inject your Post model in to you method.

Answer 2

You should bind the model using something like this:
$router->model('post', 'App\Post'); // 'post' parameter is used here
So that you can use the following:
Route::post(
'{post}/post_this_comment', // post parameter is used here
[
'as' => 'post_this_comment',
'uses' => 'PostsController#post_this_comment'
]
);
Bith parameters should match. When you bind some model using a parameter for example, $router->model('user', 'App\User') you said the framework to bind the appropriate User model when it sees a user parameter used in a route.