PHP Composer 不会用 php 5.6 安装 Drush:phpunit/phpunit 4.8.x 需要 ext-dom

PHP Composer Won't install Drush with php 5.6: phpunit/phpunit 4.8.x requires ext-dom

所以我在 CentOs 7 上工作,我一直在尝试创建一个有效的 Drupal Composer 模板 (https://github.com/drupal-composer/drupal-project) that includes a site-local Drush install (http://docs.drush.org/en/master/install/)。对于我们的项目,我们需要使用 PHP 5.6 和 Drupal 8.2。

根据上面的说明,我在 CentOS 的全新 virtualbox 安装上完成了以下操作:

已安装 git。

已安装 php 5.6:

rpm -Uvh https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm 
rpm -Uvh https://mirror.webtatic.com/yum/el7/webtatic-release.rpm 

yum install php56w php56w-opcache

现在我下载composer并全局安装:

php -r "copy('https://getcomposer.org/installer', 'composer-setup.php');" 
php -r "if (hash_file('SHA384', 'composer-setup.php') === '669656bab3166a7aff8a7506b8cb2d1c292f042046c5a994c43155c0be6190fa0355160742ab2e1c88d40d5be660b410') { echo 'Installer verified'; } else { echo 'Installer corrupt'; unlink('composer-setup.php'); } echo PHP_EOL;" 
php composer-setup.php 

mv composer.phar /usr/local/bin/compose

我可以 运行 作曲,而且似乎工作正常。

现在,根据 Drupal Composer 的说明,我们可以使用 composer 创建我们的 drupal 项目:

composer create-project drupal-composer/drupal-project:8.x-dev some-dir --stability dev --no-interaction

项目模板生成。

但是,我的问题是我不能运行

composer require drush/drush

composer update

因为我收到这些错误:

  Your requirements could not be resolved to an installable set of packages.

Problem 1
  - phpunit/phpunit 4.8.x-dev requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.9 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.8 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.7 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.6 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.5 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.4 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.35 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.34 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.33 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.32 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.31 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.30 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.3 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.29 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.28 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.27 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.26 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.25 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.24 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.23 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.22 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.21 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.20 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.2 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.19 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.18 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.17 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.16 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.15 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.14 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.13 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.12 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.11 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.10 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.1 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - phpunit/phpunit 4.8.0 requires ext-dom * -> the requested PHP extension dom is missing from your system.
  - Installation request for phpunit/phpunit ~4.8 -> satisfiable by phpunit/phpunit[4.8.0, 4.8.1, 4.8.10, 4.8.11, 4.8.12, 4.8.13, 4.8.14, 4.8.15, 4.8.16, 4.8.17, 4.8.18, 4.8.19, 4.8.2, 4.8.20, 4.8.21, 4.8.22, 4.8.23, 4.8.24, 4.8.25, 4.8.26, 4.8.27, 4.8.28, 4.8.29, 4.8.3, 4.8.30, 4.8.31, 4.8.32, 4.8.33, 4.8.34, 4.8.35, 4.8.4, 4.8.5, 4.8.6, 4.8.7, 4.8.8, 4.8.9, 4.8.x-dev].

To enable extensions, verify that they are enabled in your .ini files:
  - /etc/php.ini
  - /etc/php.d/bz2.ini
  - /etc/php.d/calendar.ini
  - /etc/php.d/ctype.ini
  - /etc/php.d/curl.ini
  - /etc/php.d/exif.ini
  - /etc/php.d/fileinfo.ini
  - /etc/php.d/ftp.ini
  - /etc/php.d/gettext.ini
  - /etc/php.d/gmp.ini
  - /etc/php.d/iconv.ini
  - /etc/php.d/json.ini
  - /etc/php.d/opcache.ini
  - /etc/php.d/phar.ini
  - /etc/php.d/shmop.ini
  - /etc/php.d/simplexml.ini
  - /etc/php.d/sockets.ini
  - /etc/php.d/tokenizer.ini
  - /etc/php.d/xml.ini
  - /etc/php.d/zip.ini
You can also run `php --ini` inside terminal to see which files are used by PHP in CLI mode.

Composer 拒绝更新。 经过几天的谷歌搜索,我似乎不知所措。我不知道我到底需要在这些文件中更改什么,而且我没有看到任何人在他们的作曲家下载中遇到同样的错误(而且大多数 post 似乎已经过时了很多年)。

任何人都可以提供任何关于我在这里缺少的东西的见解吗?

谢谢。

编辑:感谢@Oliver,我发现问题是我需要 php-xml,我使用 php5.6 安装了它:

sudo yum install php56w-xml

扩展可以在他的评论中的 link 中找到。

现在我正在弄清楚该怎么做,因为我没有在该站点上看到 drupal/core 或 easyrdf。我的新错误在这里:

  DrupalProject\composer\ScriptHandler::checkComposerVersion
  Loading composer repositories with package information
  Updating dependencies (including require-dev)
  Your requirements could not be resolved to an installable set of packages.

Problem 1
  - drupal/core 8.0.0 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.0.0-beta10 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.0.0-beta11 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.0.0-beta12 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.0.0-beta13 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.0.0-beta14 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.0.0-beta15 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.0.0-beta16 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.0.0-beta6 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.0.0-beta7 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.0.0-beta8 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.0.0-beta9 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.0.0-rc1 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.0.0-rc2 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.0.0-rc3 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.0.0-rc4 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.0.1 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.0.2 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.0.3 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.0.4 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.0.5 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.0.6 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.0.x-dev requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.1.0 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.1.0-beta1 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.1.0-beta2 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.1.0-rc1 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.1.1 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.1.10 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.1.2 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.1.3 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.1.4 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.1.5 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.1.6 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.1.7 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.1.8 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.1.9 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.1.x-dev requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.2.0 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.2.0-beta1 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.2.0-beta2 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.2.0-beta3 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.2.0-rc1 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.2.0-rc2 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.2.1 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.2.2 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.2.3 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.2.4 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.2.5 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.2.6 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.2.7 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.2.x-dev requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.3.0-alpha1 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.3.0-beta1 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.3.0-rc1 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.3.0-rc2 requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.3.x-dev requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - drupal/core 8.4.x-dev requires easyrdf/easyrdf 0.9.* -> satisfiable by easyrdf/easyrdf[0.9.0, 0.9.0-rc.1, 0.9.0-rc.2, 0.9.0-rc.3, 0.9.0-rc.4, 0.9.0-rc.5, 0.9.1, 0.9.x-dev].
  - easyrdf/easyrdf 0.9.x-dev requires ext-mbstring * -> the requested PHP extension mbstring is missing from your system.
  - easyrdf/easyrdf 0.9.1 requires ext-mbstring * -> the requested PHP extension mbstring is missing from your system.
  - easyrdf/easyrdf 0.9.0-rc.5 requires ext-mbstring * -> the requested PHP extension mbstring is missing from your system.
  - easyrdf/easyrdf 0.9.0-rc.4 requires ext-mbstring * -> the requested PHP extension mbstring is missing from your system.
  - easyrdf/easyrdf 0.9.0-rc.3 requires ext-mbstring * -> the requested PHP extension mbstring is missing from your system.
  - easyrdf/easyrdf 0.9.0-rc.2 requires ext-mbstring * -> the requested PHP extension mbstring is missing from your system.
  - easyrdf/easyrdf 0.9.0-rc.1 requires ext-mbstring * -> the requested PHP extension mbstring is missing from your system.
  - easyrdf/easyrdf 0.9.0 requires ext-mbstring * -> the requested PHP extension mbstring is missing from your system.
  - Installation request for drupal/core ~8.0 -> satisfiable by drupal/core[8.0.0, 8.0.0-beta10, 8.0.0-beta11, 8.0.0-beta12, 8.0.0-beta13, 8.0.0-beta14, 8.0.0-beta15, 8.0.0-beta16, 8.0.0-beta6, 8.0.0-beta7, 8.0.0-beta8, 8.0.0-beta9, 8.0.0-rc1, 8.0.0-rc2, 8.0.0-rc3, 8.0.0-rc4, 8.0.1, 8.0.2, 8.0.3, 8.0.4, 8.0.5, 8.0.6, 8.0.x-dev, 8.1.0, 8.1.0-beta1, 8.1.0-beta2, 8.1.0-rc1, 8.1.1, 8.1.10, 8.1.2, 8.1.3, 8.1.4, 8.1.5, 8.1.6, 8.1.7, 8.1.8, 8.1.9, 8.1.x-dev, 8.2.0, 8.2.0-beta1, 8.2.0-beta2, 8.2.0-beta3, 8.2.0-rc1, 8.2.0-rc2, 8.2.1, 8.2.2, 8.2.3, 8.2.4, 8.2.5, 8.2.6, 8.2.7, 8.2.x-dev, 8.3.0-alpha1, 8.3.0-beta1, 8.3.0-rc1, 8.3.0-rc2, 8.3.x-dev, 8.4.x-dev].

To enable extensions, verify that they are enabled in your .ini files:
  - /etc/php.ini
  - /etc/php.d/bz2.ini
  - /etc/php.d/calendar.ini
  - /etc/php.d/ctype.ini
  - /etc/php.d/curl.ini
  - /etc/php.d/dom.ini
  - /etc/php.d/exif.ini
  - /etc/php.d/fileinfo.ini
  - /etc/php.d/ftp.ini
  - /etc/php.d/gettext.ini
  - /etc/php.d/gmp.ini
  - /etc/php.d/iconv.ini
  - /etc/php.d/json.ini
  - /etc/php.d/opcache.ini
  - /etc/php.d/phar.ini
  - /etc/php.d/shmop.ini
  - /etc/php.d/simplexml.ini
  - /etc/php.d/sockets.ini
  - /etc/php.d/tokenizer.ini
  - /etc/php.d/xml.ini
  - /etc/php.d/xml_wddx.ini
  - /etc/php.d/xmlreader.ini
  - /etc/php.d/xmlwriter.ini
  - /etc/php.d/xsl.ini
  - /etc/php.d/zip.ini
You can also run `php --ini` inside terminal to see which files are used by PHP in CLI mode.

如果确定了,会post更新。

最终编辑:发现 easyrdf 需要 ext-mbstring 和 ext-pcre。 ext-pcre 安装了通用的 php 包,所以我只需要 ext-mbstring:

sudo yum install php56w-mbstring

现在,当调用 composer update 时,我的所有依赖项都已下载!现在我可以 运行 vender/bin/drush 并且命令有效,确认我的本地安装已完成!

这与作曲家无关。您只是缺少 php 扩展名。 我不知道您的 php-version 或服务器上的操作系统是什么。我 post bash 的一些示例:

编辑:现在我找到了您的版本:

CentOS-示例:

sudo yum install php56w-xml

您可以在此处找到 php 5.6 的软件包列表:https://webtatic.com/packages/php56/