An example PHP script of converting a specific data set from CSV into a specific JSON format. Used as an example of the process of handling this type of data transformation.

csv-to-json

#!/usr/bin/env php
<?php
/**
 * This script is used to convert a CSV file 
 * into json format
 *
 * Run it from the command line like so:
 * $ ./csv-to-json data.csv > data.json
 */

if (!isset($argv[1])) {
    print "Missing parameter\n";
    exit(1);
}

$file = $argv[1];

if (!file_exists($file)) {
    printf("File '%s' not found or not readable.\n", $file);
    exit(2);
}

$data = csv_to_array($file);

$persons = array();

foreach ($data as $row) {
    $person = new StdClass();

    if (!isset($row['First Name'])) {
        continue;
    }

    $person->name = $row['First Name'] . ' ' . $row['Last Name'];
    $person->date = $row['Date'];
    $person->age = $row['Age'];
    $person->pizza_topping = $row['Pizza Topping'];

    $persons[] = $person;
}

$personRegistry = new StdClass();
$personRegistry->hash = '';
$personRegistry->date = date('Y-m-d H:i:s');
$personRegistry->persons = new StdClass();
$p = $personRegistry->persons;

foreach ($persons as $person) {
    $p->{$person->name} = new StdClass();
    $p->{$person->name}->{$person->date} = $person;
}

// Make the entire registry into a string so we can give it a unique hash
$registryString = json_encode($personRegistry);
$registryHash = md5($registryString);

// Save the hash to the object
$personRegistry->hash = $registryHash;

// Output the registry
print(json_encode($personRegistry, JSON_PRETTY_PRINT));

/**
 * Convert a comma separated file into an associated array.
 * The first row should contain the array keys.
 *
 * Example:
 *
 * @param string $filename Path to the CSV file
 * @param string $delimiter The separator used in the file
 * @return array
 * @link http://gist.github.com/385876
 * @author Jay Williams <http://myd3.com/>
 * @copyright Copyright (c) 2010, Jay Williams
 * @license http://www.opensource.org/licenses/mit-license.php MIT License
 */
function csv_to_array($filename='', $delimiter=',')
{
    if(!file_exists($filename) || !is_readable($filename))
        return FALSE;

    $header = NULL;
    $data = array();
    if (($handle = fopen($filename, 'r')) !== FALSE)
    {
        while (($row = fgetcsv($handle, 1000, $delimiter)) !== FALSE)
        {
            if(!$header)
                $header = $row;
            else
                $data[] = array_combine($header, $row);
        }
        fclose($handle);
    }
    return $data;
}

data.csv