更新作曲家时需要帮助

Question

我收到以下错误，有人可以描述吗？我使用 Laravel 4 和 composer 作为依赖管理器。我尝试了几次这样做，在各种论坛上搜索并没有解决这个问题。如果有人能调查这个问题并提出解决方案，我将不胜感激。

Your requirements could not be resolved to an installable set of packages.
Problem 1
- maatwebsite/excel v1.3.7 requires phpoffice/phpexcel ~1.8.0 -> satisfiable by phpoffice/phpexcel[1.8.1, 1.8.0].
- maatwebsite/excel 1.3.2 requires phpoffice/phpexcel ~1.8.0 -> satisfiable by phpoffice/phpexcel[1.8.1, 1.8.0].
- maatwebsite/excel v1.3.0 requires phpoffice/phpexcel ~1.8.0 -> satisfiable by phpoffice/phpexcel[1.8.1, 1.8.0].
- maatwebsite/excel v1.3.1 requires phpoffice/phpexcel ~1.8.0 -> satisfiable by phpoffice/phpexcel[1.8.1, 1.8.0].
- maatwebsite/excel v1.3.3 requires phpoffice/phpexcel ~1.8.0 -> satisfiable by phpoffice/phpexcel[1.8.1, 1.8.0].
- maatwebsite/excel v1.3.4 requires phpoffice/phpexcel ~1.8.0 -> satisfiable by phpoffice/phpexcel[1.8.1, 1.8.0].
- maatwebsite/excel v1.3.5 requires phpoffice/phpexcel ~1.8.0 -> satisfiable by phpoffice/phpexcel[1.8.1, 1.8.0].
- maatwebsite/excel v1.3.6 requires phpoffice/phpexcel ~1.8.0 -> satisfiable by phpoffice/phpexcel[1.8.1, 1.8.0].
- maatwebsite/excel v1.3.7 requires phpoffice/phpexcel ~1.8.0 -> satisfiable by phpoffice/phpexcel[1.8.1, 1.8.0].
- phpoffice/phpexcel 1.8.1 requires ext-xml * -> the requested PHP extension xml is missing from your system.
- phpoffice/phpexcel 1.8.0 requires ext-xml * -> the requested PHP extension xml is missing from your system.
- phpoffice/phpexcel 1.8.1 requires ext-xml * -> the requested PHP extension xml is missing from your system.

- Installation request for maatwebsite/excel ~1.3 -> satisfiable by maatwebsite/excel[1.3.2, v1.3.0, v1.3.1, v1.3.3, v1.3.4, v1.3.5, v1.3.6, v1.3.7].

  To enable extensions, verify that they are enabled in those .ini files:
    - /etc/php.ini
    - /etc/php.d/20-bz2.ini
    - /etc/php.d/20-calendar.ini
    - /etc/php.d/20-ctype.ini
    - /etc/php.d/20-curl.ini
    - /etc/php.d/20-exif.ini
    - /etc/php.d/20-fileinfo.ini
    - /etc/php.d/20-ftp.ini
    - /etc/php.d/20-gettext.ini
    - /etc/php.d/20-iconv.ini
    - /etc/php.d/20-mcrypt.ini
    - /etc/php.d/20-mysqlnd.ini
    - /etc/php.d/20-pdo.ini
    - /etc/php.d/20-phar.ini
    - /etc/php.d/20-sockets.ini
    - /etc/php.d/20-sqlite3.ini
    - /etc/php.d/20-tokenizer.ini
    - /etc/php.d/30-mysql.ini
    - /etc/php.d/30-mysqli.ini
    - /etc/php.d/30-pdo_mysql.ini
    - /etc/php.d/30-pdo_sqlite.ini
    - /etc/php.d/40-json.ini
    - /etc/php.d/40-zip.ini

这个问题很老，我是stackoverflow的新手。我以非常错误的格式发布了这个，这不是我获得-1 声誉的原因。此问题已解决，我正在编辑此问题只是为了更好地格式化此问题并提高可读性。

Answer 1

如错误所示：the requested PHP extension xml is missing from your system

您的主机上未安装或禁用 PHP-XML 扩展。您需要先启用或安装扩展，然后才能使用需要它的包。

如果已安装，请在您的 php.ini 文件中启用扩展。如果未安装，请根据您的操作系统的需要安装扩展程序。

对于 Ubuntu 安装这个扩展你需要运行 sudo apt-get install php-xml，对于其他操作系统你需要谷歌如何安装。

Answer 2

在我的情况下，php-xml 已经安装。

root@shashank-dbserver /# apt-get install php-xml
Reading package lists... Done
Building dependency tree       
Reading state information... Done
php-xml is already the newest version.
php-xml set to manually installed.

所以，我不得不安装 php5.6-xml 而我的错误消失了。

root@shashank-dbserver /# apt-get install php5.6-xml
Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following package was automatically installed and is no longer required:
  zlib1g-dev
Use 'apt-get autoremove' to remove it.
The following NEW packages will be installed:
  php5.6-xml

此后，composer update 命令运行正常。