Merge two json array into one

Question

Tried merging two JSON responses into a single one but the problem is the data is displayed in two arrays and I want it in a single array. How do I achieve it in Lumen/Laravel

Tried contatinating two arrays or responses

 public function index(Request $request)
    {
        $post = Post::orderBy('id', 'DESC')->get();
        $post_images = PostImage::orderBy('id', 'DESC')->get();
        return $this->successResponse($posts.$post_image );        
    }

Expected:-

{
    "post": {
        "id": 14,
        "post_id": 798965728,
        "user_id": 1,
        "location": "first",
        "title": "un8852",
        "cooked_time": "1554329910",
        "dispose_time": "1554373110",
        "food_type": "nv",
        "description": "asdfg",
        "serve_quantity": 23,
        "lat": 19.08,
        "lon": 73,    
        "id": 10,
        "post_id": 798965728,
        "image_name1": null,
        "image_name2": null,
        "image_name3": null,
        "image_name4": null,
        "image_name5": null,
    },
    "st": "1",
    "msg": "success"
}

Got:-

{
   "post":"{\"id\":14,\"post_id\":798965728,\"user_id\":1,\"location\":\"first\",\"title\":\"un8852\",\"cooked_time\":\"1554329910\",\"dispose_time\":\"1554373110\",\"food_type\":\"nv\",\"description\":\"asdfg\",\"serve_quantity\":23,\"lat\":19.08,\"lon\":73,\"created_at\":\"2019-04-04 10:20:18\",\"updated_at\":\"2019-04-04 10:20:18\"}{\"id\":10,\"post_id\":798965728,\"image_name1\":null,\"image_name2\":null,\"image_name3\":null,\"image_name4\":null,\"image_name5\":null,\"created_at\":\"2019-04-04 10:20:18\",\"updated_at\":\"2019-04-04 10:20:18\"}",
   "st":"1",
   "msg":"success"
}

Answer 1

There are some missing pieces there, but I think I see what's happening.

Based on the result you're getting, it looks like $posts and $post_image in this code are eloquent models.

return $this->successResponse($posts.$post_image ); 

When you concatenate them, their __toString() methods convert them to strings, which is done using the toJson() method. So basically you have two JSON objects stuck together, which isn't valid JSON, and then the successResponse() method encodes them again.

To merge them, you can convert them to arrays, merge those, then pass the result to successResponse().

$merged = array_merge($posts->toArray(), $post_image->toArray());
return $this->successResponse($merged);

The result you want is impossible, though. The "post" object has two different values of "id". You'll only be able to get one. If you use

$merged = array_merge($posts->toArray(), $post_image->toArray());

Then the id value of the second object will replace the first one. If you want to keep the first id value, you need to use union instead of array_merge.

$merged = $a->toArray() + $b->toArray(); 

Answer 2

I think you can't concatenate 2 JSON objects as strings.

The proper way would be to:

1. Get the Post and the PostImage objects

   $post = Post::orderBy('id', 'DESC')->get();

   $post_images = PostImage::orderBy('id', 'DESC')->get();

2. Serialize the Post object https://laravel.com/docs/5.8/eloquent-serialization

3. Use the method described below to add each field of the PostImage object (image_name1 .. image_name5) to the JSON How to add attribute in JSON in PHP?

4. Return the JSON

Update:

Post::orderBy('id','DESC')->get()-> first() returns one object.

Post::orderBy('id','DESC')->get() returns a collection of objects and it would require a different approach.

Try this:

$post = Post::orderBy('id', 'DESC')->get();

$post->map(function ($item, $key) {
    $post_images = PostImage::where('post_id', $item->id)->get()->first();
    $item->setAttribute('image_name1',$post_images->image_name1);
    $item->setAttribute('image_name2',$post_images->image_name2);
    $item->setAttribute('image_name3',$post_images->image_name3);
    $item->setAttribute('image_name4',$post_images->image_name4);
    $item->setAttribute('image_name5',$post_images->image_name5);
    return $item;
});

return $this->successResponse($posts);

Answer 3

You can definitely concatenate two JSON arrays, You have to parse the objects and concatenate them and re stringify.

This question might be answered here also. https://stackoverflow.com/a/10384890/1684254