所以我正在使用CentOs 7，我一直在尝试创建一个有效的Drupal Composer模板（https://github.com/drupal-composer/drupal-project），其中包含一个站点本地Drush安装（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。
根据上述说明，我在CentOS的干净虚拟机安装上完成了以下操作：
已安装的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
我可以运行作曲家，它似乎工作正常。
现在按照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
项目模板构建。
然而，我的问题是我无法运行
composer require drush/drush
或
composer update
因为我收到了这些错误：
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。我不知道我需要在这些文件中做些什么改变，而且我没有看到任何人在他们的作曲家下载中出现同样的错误（而且大多数帖子看起来已经过时了很多年）。
任何人都可以提供任何有关我在这里缺少的信息吗？
谢谢。
编辑：感谢@Oliver我发现问题是我需要php-xml，我为php5.6安装使用：sudo yum install php56w-xml
可以在评论的链接中找到扩展程序。
现在我正在搞清楚要做什么，因为我没有看到该网站上列出的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.
如果想出来，会发布更新。
最终编辑：想象出easyrdf需要ext-mbstring和ext-pcre。 ext-pcre安装了常见的php包，所以我需要的只是ext-mbstring：
sudo yum install php56w-mbstring
现在，当调用composer update时，我的所有依赖项都被下载了！现在我可以运行vender / bin / drush并且命令有效，确认我的本地安装完成了！
答案 0 :(得分：2)
这不是与作曲家有关的。你只是错过了一个php扩展。 我不知道你的php版本是什么，或者你的服务器上有什么操作系统。我发布了一些关于bash的例子：
编辑：现在我已经找到了你的版本：
的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/