Make post_id as the key for my next array - php

Question

So I'm trying to figure out this small piece, but I'm completely stuck and could use some assistance. I will break the code down into sections for understanding.
This will grab 5 of my posts:
$post_list = get_posts([
'post_type' => 'post',
'posts_per_page' => 5,
]);
Output per post:
Array
(
[0] => WP_Post Object
(
[ID] => 59343
)
)
Then I'm adding the returned ID's into an array using the below code:
$post_authors = [];
foreach ($post_list as $key => $post) {
$post_author = \get_post_author($post->ID);
$post_authors[] = $post_author['ID'];
}
print_r($post_authors);
This outputs me the following array:
Array
(
[0] => 52714
[1] => 0
[2] => 3339
[3] => 0
[4] => 0
)
Then I'm matching my custom post author meta associated with the post:
$test_id = [];
foreach ($post_authors as $author) {
$test_id[] = get_post_meta($author, '_test_id');
}
print_r($test_id);
This is the output that I get:
Array
(
[0] => Array
(
[0] => 7899
)
[1] =>
[2] => Array
(
[0] => 3487
)
[3] =>
[4] =>
)
Is there a way that I can map the above posts as keys and then have the id as outputs? Also skip the empty values on get_posts().
For example:
Array
(
[52714] => 7899
[3339] => 3487
)
All help would be appreciated!

Answer 1

If I understand your question correctly then you can use this logic.
$posts = array(5676,6767,0,0,564,898);
$test_id = [];
foreach ($posts as $key =>$value) {
$test_id[$value] = $key; // get_post_meta($author, '_test_id');
}
print_r($test_id);
//output
Array
(
[5676] => 0
[6767] => 1
[0] => 3
[564] => 4
[898] => 5
)