can't attach topic_id in the comment table - laravel

Question

I am making a forum where users can create topics and leave a reply just like this forum.
I made a relationship just like below.However, when I save an article the topic_id does not get attached.I think the saveReply method is wrong.
Also,in this case how do you pass comments on the particular post to the view in the show method??
I am a noob,so if my question is vague I am sorry,but any help will be appreciated!!
Route
Route::group(['middleware' => 'web'], function () {
Route::get('forums','ForumsController#index');
Route::get('forums/create','ForumsController#create');
Route::post('forums', 'ForumsController#store');
Route::get('forums/{category_id}/{title}','ForumsController#show');
Route::post('forums/{category_id}/{title}', 'ForumsController#saveReply');
});
forumcontroller
class ForumsController extends Controller
{
public function index()
{
$categories = Category::all();
$topics = Topic::latest()->get();
return view('forums.index',compact('categories','topics'));
}
public function create()
{
$categories = Category::lists('title', 'id');
return view('forums.create', compact('categories'));
}
public function store(Request $request)
{
Auth::user()->topics()->save(new Topic($request->all()));
flash()->success('投稿しました','success');
return redirect('forums');
}
public function show($category_id, $title)
{
Topic::where(compact('category_id','title'))->first();
return view('forums.post', compact('topic'));
}
public function saveReply (Request $request)
{
Auth::user()->comments()->save(new Comment($category_id,$request->all()));
flash()->success('投稿しました','success');
return redirect()->back();
}
}
topic model
<?php
namespace App;
use Illuminate\Database\Eloquent\Model;
class topic extends Model
{
protected $fillable = [
'title',
'body',
'category_id'
];
public function category()
{
return $this->belongsTo('App\category');
}
public function user()
{
return $this->belongsTo('App\User');
}
public function comments()
{
return $this->hasMany('App\Comment');
}
}
user model
<?php
namespace App;
use Illuminate\Foundation\Auth\User as Authenticatable;
class User extends Authenticatable
{
/**
* The attributes that are mass assignable.
*
* #var array
*/
protected $fillable = [
'name', 'email', 'password',
];
/**
* The attributes excluded from the model's JSON form.
*
* #var array
*/
protected $hidden = [
'password', 'remember_token',
];
public function articles()
{
return $this->hasMany('App\Article');
}
public function topics()
{
return $this->hasMany('App\Topic');
}
public function comments()
{
return $this->hasMany('App\Comment');
}
}
comment model
class Comment extends Model
{
protected $fillable = [
'reply',
'user_id',
'topic_id'
];
public function topic()
{
return $this->belongsTo('App\Topic');
}
public function user()
{
return $this->belongsTo('App\User');
}
}
comment table
class CreateCommentsTable extends Migration
{
public function up()
{
Schema::create('comments', function (Blueprint $table) {
$table->increments('id');
$table->text('reply');
$table->integer('user_id')->unsigned();
$table->integer('topic_id')->unsigned();
$table->timestamps();
});
}
public function down()
{
Schema::drop('comments');
}
}

Answer 1

The Request::all returns an array of all inputs so when you are doing:
new Comment($category_id,$request->all())
You'll get something like this:
1['some' => 'thing', 'other'=> 'values']
Which could be the problem so try this instead:
new Comment(array_merge(['category_id' => $category_id ], $request->all())
When on development/local environment, set the debug true so you'll get meaningful error messages so you can findout the exect problem easily.