PHP compare two arrays and return only unique array values

Question

Finishing up an open source Domain Registrar plugin and having a few troubles with determining when a change has been made.

$saved = array(
        array( 'domain' => 'mydomain.com', 'record' => 'A', 'value' => '8.8.8.8' ),
        array( 'domain' => 'mydomain.com', 'record' => 'NS', 'value' => 'ns1.mydomain.com' )
    );

$new = array(
        array( 'domain' => 'mydomain.com', 'record' => 'A', 'value' => '4.4.4.4' ),
        array( 'domain' => 'mydomain.com', 'record' => 'NS', 'value' => 'ns1.mydomain.com' ),
        array( 'domain' => 'sub.mydomain.com', 'record' => 'A', 'value' => '1.2.3.4' ),
    );

$saved is the values already saved at the domain registrar, and is only being used for comparison.

$new is the array returned from application that processed the form on the website.

I need to somehow only return arrays that have values that were updated or that do not already exist/match from $saved.

Basically the return array i'm looking for would be:

array(
    array( 'domain' => 'mydomain.com', 'record' => 'A', 'value' => '4.4.4.4' )
    array( 'domain' => 'sub.mydomain.com', 'record' => 'A', 'value' => '1.2.3.4' ),
);

Because in $saved the value was updated from 8.8.8.8 to 4.4.4.4, and the sub.mydomain.com did not match any array from $saved meaning it's a new entry.

Using array_intersect I was able to get it to return the array that had it's values updated, but unfortunately it still includes the arrays that matched as well. If I could somehow have those removed that would be exactly what I need.

Here's a demo: http://glot.io/php/529b0c6d2fd16fe221f86bb521155384

Maybe use array_uintersect with a callback to check if the arrays match and unset? Looking for some help as i'm stuck on this now.

Thanks!!

Answer 1

Well in this case you could flatten them thru serializing, them map, them finally array_dif()

$result = array_map('unserialize', array_diff(array_map('serialize', $new), array_map('serialize', $saved)));

Should produce based on example:

Array
(
    [0] => Array
        (
            [domain] => mydomain.com
            [record] => A
            [value] => 4.4.4.4
        )

    [2] => Array
        (
            [domain] => sub.mydomain.com
            [record] => A
            [value] => 1.2.3.4
        )

)

Answer 2

array_udiff should work here.

Something along the lines of the following comparison function as a custom callback should do the trick:

$saved = array(
        array( 'domain' => 'mydomain.com', 'record' => 'A', 'value' => '8.8.8.8' ),
        array( 'domain' => 'mydomain.com', 'record' => 'NS', 'value' => 'ns1.mydomain.com' )
    );

$new = array(
        array( 'domain' => 'mydomain.com', 'record' => 'A', 'value' => '4.4.4.4' ),
        array( 'domain' => 'mydomain.com', 'record' => 'NS', 'value' => 'ns1.mydomain.com' ),
        array( 'domain' => 'sub.mydomain.com', 'record' => 'A', 'value' => '1.2.3.4' ),
    );


function cmpr($a, $b) {
    foreach($a as $k=>$v) {
        if ($b[$k] !== $v)
            return -1;
    }
    return 0;
}

var_dump(array_udiff($new, $saved, 'cmpr'));

The output should look something like what you expected:

array(2) {
  [0]=>
  array(3) {
    ["domain"]=>
    string(12) "mydomain.com"
    ["record"]=>
    string(1) "A"
    ["value"]=>
    string(7) "4.4.4.4"
  }
  [2]=>
  array(3) {
    ["domain"]=>
    string(16) "sub.mydomain.com"
    ["record"]=>
    string(1) "A"
    ["value"]=>
    string(7) "1.2.3.4"
  }
}