laravel-admin报错The "https://packgist.phpcomposer.com/packages.json" file could not be downloaded: php_network_getaddresses: getaddrinfo failed: ��֪������������� failed to open stream: php_network_ge

由于packagist更改导致的报错。例如：

可以把composer.json中修改一下

"packagist": {
"type": "composer",
"url": "https://packagist.phpcomposer.com"
}
修改成

"packagist": {
"type": "composer",
"url": "https://packagist.laravel-china.org"
}

原文：https://blog.csdn.net/kangsf1989/article/details/82969407