Composer 报错 Error while processing content unencoding: Unknown failure within ..

Composer 报错:

https://mirrors.aliyun.com/composer could not be fully loaded (curl error 61 while downloading https://mirrors.aliyun.com/composer/p2/laravel/laravel.json: Error while processing content unencoding: Unknown failure within decompression software.), package information was loaded from the local cache and may be out of date

[Composer\Downloader\TransportException]                                                                                                                   
curl error 61 while downloading https://mirrors.aliyun.com/composer/p2/laravel/laravel.json: Error while processing content unencoding: Unknown failure wi  
thin decompression software. 

[Composer\Downloader\TransportException] Error while processing content unencoding: Unknown failure within decompression software. 错误提示是说 解压文件发生错误，检查环境的拓展并没有缺少压缩拓展。

检查运行命令之后返回结果的一段后 发现并不是因为压缩拓展的问题。最后一句话中 package information was loaded from the local cache and may be out of date 说明存在的问题是 本地缓存过期引起的。所以 清除 composer 本地缓存就可以解决。

清除缓存的命令：

$ composer clearcache