How to add custom properties to Laravel paginate json response - json

Question

I have the following simple index method:
public function index()
{
// dd(Poll::paginate(2));
return response()->json(Poll::paginate(2),200);
}
The output of that method is looks like the following json object:
{
"current_page": 1,
"data": [
{
"id": 1,
"title": "I suppose?' said Alice. 'Why, you don't know.",
"created_at": "2018-09-14 16:42:11",
"updated_at": "2018-09-14 16:42:11"
},
{
"id": 2,
"title": "Alice; but she knew that it seemed quite.",
"created_at": "2018-09-14 16:42:11",
"updated_at": "2018-09-14 16:42:11"
}
],
"first_page_url": "http://127.0.0.1:8000/polls?page=1",
"from": 1,
"last_page": 6,
"last_page_url": "http://127.0.0.1:8000/polls?page=6",
"next_page_url": "http://127.0.0.1:8000/polls?page=2",
"path": "http://127.0.0.1:8000/polls",
"per_page": 2,
"prev_page_url": null,
"to": 2,
"total": 11
}
I want to add another array property after "total: 11" attribute such as:
,
"anotherData" : [
"userId": 1,
"userName": "john10",
"message": "This is a message"
]
I have tried to understand how response()->json() works, so it can extract some data from LengthAwarePaginator object which it is the output of Poll::paginate(2) from this resource, but I could not able to understand how does it able to get an array from LengthAwarePaginator that holds the resultant keys in the json object?!

Answer 1

From the regarded resource above, the json() method takes an array and, I guess that, if the parameter is not an array, it tries to convert it to array, specially if it is an object like LengthAwarePaginator, so it may use toArray() method.
I have tried replacing return response()->json(Poll::paginate(2),200) with return response()->json(Poll::paginate(2)->toArray,200), then I have got the same output. Hence, I have decided to replace the code of my index method to be like the following:
public function index()
{
//dd(Poll::paginate(2)->toArray());
$output = Poll::paginate(2)->toArray();
$output['userData'] = ['userId' => \Auth::user()->id, 'userEmail' => \Auth::user()->email];
return response()->json($output,200);
}
The resultant output is:
...
"path": "http://127.0.0.1:8000/polls",
"per_page": 2,
"prev_page_url": null,
"to": 2,
"total": 11,
"userData": {
"userId": 1,
"userEmail": "lion#example.com"
}
}

Answer 2

If you're directly responding with the paginated data, a better option would be to wrap it in a Resource Collection and adding meta data to it.
This is how I implemented it.
CategoryController.php
public function index()
{
return new CategoryCollection(Category::paginate(10));
}
CategoryCollection.php
public function toArray($request)
{
return [
'status' => 1,
'message' => 'Success',
'data' => $this->collection,
];
}
Since Collection extends JsonResource, your response would automatically be converted to JSON when returned from the Controller.