composer常见异常问题处理

0、更换composer镜像源：

1）更换成阿里镜像：

composer config -g repo.packagist composer https://mirrors.aliyun.com/composer/

2）更换成Laravel China镜像：

composer config -g repo.packagist composer https://packagist.laravel-china.org

3）更换成中国全量镜像：

composer config -g repo.packagist composer https://packagist.phpcomposer.com

1、Deprecation Notice: strlen(): Passing null to parameter #1

需要执行：

composer global require fxp/composer-asset-plugin --no-plugins

2、composer install 安装出现Your requirements could not be resolved to an installable set of packages.

出现上面的问题是因为不匹配composer.json要求的版本。

解决：

composer install --ignore-platform-reqs

或者：

composer update --ignore-platform-reqs

3、No composer.lock file present. Updating dependencies to latest instead of installing from lock file. See https://getcomposer.org/install for more information.

composer install --ignore-platform-reqs