how to structure php nodes [closed]

If you want to generate JSON, you "must" format it as an array, using the indexes.

You can use several forms for this:

Form 1:

$array = ['nodes' => ["name" => "Baixo Alentejo",  "color": "#f0e68d"]];

echo $json = json_encode($array);

Form 2:

$array['nodes']["name"] = "Baixo Alentejo";
$array['nodes']["color"] = "#f0e68d";

echo $json = json_encode($array);

Form 3:

$array['nodes'][] = ["name" => "Baixo Alentejo", "color" => "#f0e68d"];

echo $json = json_encode($array);

Result (in all cases):

{"nodes":{"name":"Baixo Alentejo","color":"#f0e68d"}}

The easiest way to adapt your code would be to change : to => and remove this as string , resulting in:

$nodes['nodes'][] = ['name' => $row['name'], 'color' => $row['color']];

echo json_encode($nodes);

So?

$nodes[] =  '"name": "' . $row['name'] . '", "color": "' . $row['color'] . '"'; 
//Array
//(
//    [0] => "name": "Baixo Alentejo", "color": "#f0e68d\r\n"
//)

To format as JSON , use json_encode :

$nodes['nodes']['name'] = $row['name'];
$nodes['nodes']['color'] = $row['color'];

$nodeEncode = json_encode($nodes); 
$nodeDecode = json_decode($nodeEncode);

echo "json_encode \n";
var_dump($nodeEncode);

echo "json_decode \n";
foreach ($nodeDecode as $node){
    echo $node->name . "\n";
    echo $node->color . "\n";
}

// json_encode 
// string(53) "{"nodes":{"name":"Baixo Alentejo","color":"#f0e68d"}}"

// json_decode 
// Baixo Alentejo
// #f0e68d

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