How can update Current Timezone in the main configuration?

config/app.php

'timezone' => 'America/New_York',

I'm trying to update my app.timezone base on clientTimeZone Asia/Kolkata

$date = new DateTime();
$timeZone = $date->getTimezone();
echo $timeZone->getName().PHP_EOL;

$timezone_offset_minutes = 330; 
$clientTimeZone = timezone_name_from_abbr("", $timezone_offset_minutes*60, false);
echo $clientTimeZone .PHP_EOL;

Session::put('clientTimeZone',$clientTimeZone);
config('app.timezone', $clientTimeZone);

$date = new DateTime();
$timeZone = $date->getTimezone();
echo $timeZone->getName() .PHP_EOL;

This is the result

America/New_York 
Asia/Kolkata 
America/New_York

I have a feeling that this

config('app.timezone', $clientTimeZone);

is not taking any effect

Solution 1:

DateTime class accept two args, the second one is ?DateTimeZone $timezone = null. If it's omitted or null, the current timezone will be used.

$timezone = new DateTimeZone('America/New_York');
$date = new DateTime('now', $timezone);   

The Laravel's app.timezone config doesn't affect directly to DateTime.

On bootstrapping Laravel app it set up timezone this way

date_default_timezone_set($config->get('app.timezone', 'UTC'));

To work with client timezone you may set up it globally during session

$timezone_offset_minutes = 330; 
$clientTimeZone = timezone_name_from_abbr("", $timezone_offset_minutes*60, false);
date_default_timezone_set($clientTimeZone);

Remember it doesn't affect any other apps, i.e. mysql. Mysql still will use app.timezone readed on application bootstrap.

I propose to pass client timezone to any methods, functions and use it this way

$timezone_offset_minutes = 330; 
$clientTimeZone = timezone_name_from_abbr("", $timezone_offset_minutes*60, false);
$this->getClientDateTime(new DateTimeZone($clientTimeZone));

//...

public function getClientDateTime(DateTimeZone $dateTimeZone): string
{
    return new DateTime('now', $dateTimeZone->format('Y-m-d H:i:s');
}