How to merge fields in a table?

Question

Laravel

Laravel version 5.0.34
I want to display all products that belong to categories.
Please tell me why when calling

$comments = \App\category::find(1)->products()->all();

Error returned "Call to a member function products() on a non-object"
Made a one-to-many relationship.
Model with product table:

<?php namespace App;
use Illuminate\Database\Eloquent\Model;
class product extends Model  {
  protected $table = 'products';
  public function category()
  {
    return $this->belongsTo('App\category','id', 'category_id');
  }

 
}

Model with category table:

<?php namespace App;


use Illuminate\Database\Eloquent\Model;


class category extends Model  {
  protected $table = 'categories';



  public function products()
  {
    return  $this->hasMany('App\product' ,'category_id', 'id');
  }


}

I call this connection from the controller method:

<?php namespace App\Http\Controllers;


use App\category;
use App\product;
....
 public function categoryItem(category $categoryModel,product $productModel ) {
        $comments = \App\category::find(1)->products()->all();
    }

tables:

CREATE TABLE `products` (
  `id` INT(11) NOT NULL AUTO_INCREMENT,
  `title` VARCHAR(255) NOT NULL DEFAULT '0',
  `img` VARCHAR(255) NOT NULL DEFAULT '0',
  `intro_text` VARCHAR(255) NOT NULL DEFAULT '0',
  `status` INT(1) NOT NULL DEFAULT '0',
  `full_text` TEXT NOT NULL,
  `slug` VARCHAR(50) NOT NULL,
  `price` INT(11) NOT NULL,
  `category_id` INT(11) NULL DEFAULT NULL,
  PRIMARY KEY (`id`)
)
COLLATE='utf8_general_ci'
ENGINE=InnoDB
AUTO_INCREMENT=6
;

CREATE TABLE `categories` (
  `id` INT(10) UNSIGNED NOT NULL AUTO_INCREMENT,
  `title` VARCHAR(255) NOT NULL,
  `full_text` TEXT NOT NULL,
  `created_at` TIMESTAMP NOT NULL DEFAULT '0000-00-00 00:00:00',
  `updated_at` TIMESTAMP NOT NULL DEFAULT '0000-00-00 00:00:00',
  `slug` VARCHAR(50) NULL DEFAULT NULL,
  PRIMARY KEY (`id`)
)
COLLATE='utf8_general_ci'
ENGINE=InnoDB
AUTO_INCREMENT=7
;

Answer 1

First, check if you have a category with this id.
You no longer need the second moment of all(), since the query is executed by find().
And it's better to organize such a request a little differently:
And one more fix:

<?php namespace App\Http\Controllers;


use App\category;
use App\product;

public function categoryItem(category $categoryModel,product $productModel ) {
    $comments = category::with('products')->find($id);

}