composer
查看当前版本
composer --version or composer -v更新版本（慎用）
composer selfupdate 或者 composer self-update回退composer 版本
composer self-update --rollback清理缓存
composer clearcache查看Composer配置中的镜像地址：
composer config -gl修改镜像地址为中国镜像：
composer config -g repo.packagist composer Packagist / Composer其它镜像
#阿里云
composer config -g repo.packagist composer https://mirrors.aliyun.com/composer/
#腾讯云
composer config -g repo.packagist composer PHP Composer
