JSON to CSV converter.

json2csv.php

<?php

if ($argc < 2) {
    echo 'Usage: json2csv.php [input.json] output.csv', PHP_EOL;

    exit(1);
}

$input = fopen($argc === 3 ? $argv[1] : 'php://stdin', 'r');

if ($input === false) {
    echo 'Invalid input.', PHP_EOL;

    exit(2);
}

$json = '';

while (!feof($input)) {
    $json .= fread($input, 1024);
}

fclose($input);

$data = json_decode($json);
$output = fopen(array_pop($argv), 'w');

foreach ($data as $fields) {
    fputcsv($output, (array) $fields);
}

fclose($output);