PHP - Group similar key in one Object - php

Question

I have one array with objects, and what I would like to achieve is to group the objects if a similar key already exists. What my JSON output looks like is,
[
{
"id": 37,
"slug": "red",
"stock": true,
"name": "Red",
"default": 0,
"sizes": "38"
},
{
"id": 38,
"slug": "red",
"stock": true,
"name": "Red",
"default": 0,
"sizes": "40"
},
{
"id": 34,
"slug": "red",
"stock": true,
"name": "Red",
"default": 0,
"sizes": "36"
},
{
"id": 26,
"slug": "green",
"stock": true,
"name": "Green",
"default": 0,
"sizes": "48"
}
What I would like to achieve is to group the similar slugs, and have an array of all the sizes in one. So something like this below,
[
{
"slug": "red",
"name": "Red",
"sizes" : [{
"id": 37,
"slug": "red",
"stock": true,
"name": "Red",
"default": 0,
"sizes": "38"
},
{
"id": 38,
"slug": "red",
"stock": true,
"name": "Red",
"default": 0,
"sizes": "40"
},
{
"id": 34,
"slug": "red",
"stock": true,
"name": "Red",
"default": 0,
"sizes": "36"
}]
}, {
"slug": "green",
"name": "Green",
"sizes": [{
"id": 26,
"slug": "green",
"stock": true,
"name": "Green",
"default": 0,
"sizes": "48"
}]
}
]
I'm not so much of a PHP guru, so been trying to figure out all day how to do this searching all over, and hoping someone fluent in PHP can help me out.

Answer 1

You can use one loop to group your result by slug first and then use another to get what you want. Let's try like this way-
<?php
$json = '[{"id":37,"slug":"red","stock":true,"name":"Red","default":0,"sizes":"38"},{"id":38,"slug":"red","stock":true,"name":"Red","default":0,"sizes":"40"},{"id":34,"slug":"red","stock":true,"name":"Red","default":0,"sizes":"36"},{"id":26,"slug":"green","stock":true,"name":"Green","default":0,"sizes":"48"}]';
$array = json_decode($json,1);
$expected = [];
foreach($array as $v) {
$expected[$v['slug']][] = $v;
}
$expected_v2 = [];
foreach($expected as $k1=>$v1) {
array_push($expected_v2,['slug'=>$k1,'name'=>ucfirst($k1),'sizes'=>$v1]);
}
//print_r($expected_v2);
echo json_encode($expected_v2);
?>
Output:
[{"slug":"red","name":"Red","sizes":[{"id":37,"slug":"red","stock":true,"name":"Red","default":0,"sizes":"38"},{"id":38,"slug":"red","stock":true,"name":"Red","default":0,"sizes":"40"},{"id":34,"slug":"red","stock":true,"name":"Red","default":0,"sizes":"36"}]},{"slug":"green","name":"Green","sizes":[{"id":26,"slug":"green","stock":true,"name":"Green","default":0,"sizes":"48"}]}]
DEMO: https://3v4l.org/WfbsX

Answer 2

You can use `array_reduce to achieve this :
$json = '[{"id":37,"slug":"red","stock":true,"name":"Red","default":0,"sizes":"38"},{"id":38,"slug":"red","stock":true,"name":"Red","default":0,"sizes":"40"},{"id":34,"slug":"red","stock":true,"name":"Red","default":0,"sizes":"36"},{"id":26,"slug":"green","stock":true,"name":"Green","default":0,"sizes":"48"}]';
$input = json_decode($json, true);
$output = array_reduce(array_reduce($input, function ($carry, $item) {
$carry[$item['slug']][] = $item;
return $carry;
}, []), function ($carry, $group) {
$carry[] = [
'slug' => $group[0]['slug'],
'name' => $group[0]['name'],
'sizes' => $group
];
return $carry;
}, []);