Laravel & PHP: Return special formatted JSON

Question

After doing a query, how can I create and echo a formatted JSON like this:

{
  "results": [
    {
      "user_id": "1",
      "name": "Apple",
      "address": "7538 N LA CHOLLA BLVD",
      "city": "Palo Alto",
      "state": "CA",
      "latlon": [
        -111.012654,
        32.339807
      ],
    },
    {
      "user_id": "2",
      "name": "Microsoft",
      "address": "75 S BWY STE 400",
      "city": "Palo Alto",
      "state": "CA",
      "latlon": [
        -73.764497,
        41.031858
      ],
    },
   ],

  "meta": {
    "page": 1,
    "per_page": 10,
    "count": 493,
    "total_pages": 50
  }
}

This is my current query:

public function getAgenciesJson() {

    $agencies = DB::table('users')->where('type','a')->orWhere('type','l');

}

Haven't figured out how to output JSON like that, considering I have a "latlon" field like [-111.012654,32.339807], also a "results" tag and a "meta" tag.

Thanks in advance

Answer 1

What you need is something called a transformer (or presenter) to convert your raw model into a format that can be sent to your users.

A very popular package is called Fractal (http://fractal.thephpleague.com/) by Phil Sturgeon. There's a Laravel package, that might make it a bit easier to use, called Larasponse (https://github.com/salebab/larasponse).

Phil actually a blog post about this just the other day - https://philsturgeon.uk/api/2015/05/30/serializing-api-output/ - that goes into why you should always have some kind of transformer between your models and what you send to your users.

There's also a guide about using Larasponse and Fractal that might be of use here - http://laravelista.com/laravel-fractal/.

The gist of it boils down to passing the model through another class that will take the models values and build an array/object in a known/fixed format, e.g. (from Phil's blog post)

return [
    'id'      => (int) $book->id,
    'title'   => $book->title,
    'year'    => (int) $book->yr,
    'author'  => [
        'name'  => $book->author_name,
        'email' => $book->author_email,
    ],
    'links'   => [
        [
            'rel' => 'self',
            'uri' => '/books/'.$book->id,
        ]
    ]
];

This way you're not exposing your original field names and if at any point your column names should change you only need to update that in 1 place rather than having to get any user of your JSON to update their site/app. It will also allow you to do string manipulation of your latlon column so that you can split it into 2 different values.

Using a slightly modified example from the Fractal documentation. Say you have a transformer for a User

class UserTransformer extends Fractal\TransformerAbstract
{
    public function transform(User $user) 
    {
        return [
            'id' => (int) $user->id,
            'name' => $user->first_name . ' ' . $user->last_name,
        ];
    }
}

You can then use this class to either transform a single item of a collection

$user = User::find(1);
$resource = new Fractal\Resource\Item($user, new UserTransformer);

// Or transform a collection
// $users = User::all();
// $resource = new Fractal\Resource\Collection($users, new UserTransformer);

// Use a manager to convert the data into an array or json
$json = (new League\Fractal\Manager)->createData($resource)->toJson();

Fractal includes a paginator adapter for Laravel that can be used straight away

$paginator = User::paginate();
$users = $paginator->getCollection();

$resource = new Collection($users, new UserTransformer);
$resource->setPaginator(new IlluminatePaginatorAdapter($paginator));