Integrity constraint violation: 1048 Column 'post_id' cannot be null - mysql

Question

I'm using laravel 5.5 and im trying to add a comment to a post and i get the following error when i submit to the form
"SQLSTATE[23000]: Integrity constraint violation: 1048 Column
'post_id' cannot be null (SQL: insert into comments (comment_body,
user_id, post_id, updated_at, created_at) values (sdsd, 1, ,
2017-12-03 12:29:58, 2017-12-03 12:29:58))
im going to be using: <% %> is for angular, just letting everyone know.
In tinker this works
Comment::create(['comment_body' => 'this works', 'user_id'=> 1, 'post_id'=>8]);
**Route*
Route::post('post/comment', 'CommentController#create');
Post Model
use App\User;
use App\Like;
use App\Comment;
use Illuminate\Notifications\Notifiable;
use Illuminate\Foundation\Auth\User as Authenticatable;
class Post extends Authenticatable
{
protected $fillable = [
'title',
'body',
'user_id',
'created_at',
];
public function user()
{
return $this->belongsTo(User::class);
}
public function likes()
{
return $this->hasMany('App\Like');
}
public function comments()
{
return $this->hasMany('App\Comment');
}
Comment Model
class Comment extends Model
{
protected $fillable = [
'comment_body',
'user_id',
'post_id'
];
public function user()
{
return $this->belongsTo('App\User');
}
public function post()
{
return $this->belongsTo('App\Post');
}
}
CommentConroller
public function create(Request $request, Post $post)
{
$data = request()->validate([
'comment_body' => 'required|max:1000'
]);
$data['user_id'] = auth()->user()->id;
$data['name'] = auth()->user()->name;
$data['post_id'] = $post->id;
$post = Comment::create($data);
$response = new Response(json_encode($data));
$response->headers->set('Content-Type', 'application/json');
if(!$response){
return 'something went wrong';
}
return response()->json($data);
}
Html
<div class="comment-class animated bounceInUp" ng-show="writecomment">
<div class="panel-body">
<ng-form ng-model="commentForm" name="commentForm" method="POST" novalidate>
<div class="form-group">
<label>Write a Comment</label>
<textarea ng-model="post.comment" type="text" class="form-control" name="comment_body" cols="2" rows="2"></textarea>
</div>
<button id="eli-style-button" ng-click="addComment(post)" class="btn btn-primary" type="submit">Submit</button>
</form>
</div>
<!-- END Comment form Inside Ng-repeat -->
</div>
<!-- End of ng-repeat post in mypost -->
</div>
Main.js
$scope.addComment = function(post){
$http.post('/post/comment',{
comment_body: post.comment,
}).then(function(result){
console.log(result.data);
$scope.myposts.push(result.data);
});
};

Answer 1

In order to use route model binding, you have to include the post as a parameter in your route:
Route::post('post/{post}/comment', 'CommentController#create');
Then call it like this:
$http.post('/post/' + post.id + '/comment' ...
Right now in your controller you are getting an empty Post instance that has no ID.