HT_DASHBOARD/app/Models/HtpmsCustomer/HtpmsCustomerConnectionSwitch.php

<?php

namespace App\Models\HtpmsCustomer;

use Exception;
use Illuminate\Support\Facades\Config;
use PDO;

class HtpmsCustomerConnectionSwitch
{
    public static function switch(int $customerId): void
    {

        if (!self::isEnable($customerId)) {
            throw new Exception("顧客切り替え不正");
        }

        $connectionsRoot = "database.connections";
        $connectionHtmsCustomer = "htpms_customer";

        $databaseNameKey = "{$connectionsRoot}.{$connectionHtmsCustomer}.database";
        $currentDatabaseName = config($databaseNameKey);

        $afterDatabaseName = "htpms_{$customerId}";

        if ($currentDatabaseName !== $afterDatabaseName) {
            Config::set($databaseNameKey, $afterDatabaseName);
        }
    }

    public static function isEnable(int $customerId): bool
    {
        $dsn = sprintf(
            'pgsql:dbname=htpms_%d host=%s port=%d',
            $customerId,
            config("database.connections.htpms_customer.host"),
            config("database.connections.htpms_customer.port"),
        );
        $user =    config("database.connections.htpms_customer.username");
        $password = config("database.connections.htpms_customer.password");
        try {
            new PDO($dsn, $user, $password);
        } catch (Exception $e) {
            return false;
        }

        return true;
    }
}