在 rails 上通过 bundle (Gemfile) 安装 mysql2 -v '0.3.19'

Question

在 OSX Lion 上的 Gemfile 中列出“mysql2”时尝试“捆绑安装”时出错。我正在用 Rails 构建一个应用程序。如果我运行“捆绑安装”，它会永远挂起。首先，我尝试按照建议将 gem 文件修改为 'gem 'mysql2', :git => 'git://github.com/sodabrew/mysql2.git', :ref => 'a2800f'' 来解决这个问题在这里：https://github.com/brianmario/mysql2/pull/654。无限循环得到修复，我成功运行了 'bundle install' 但是当我运行 'rake db:create' 时，我收到了这个错误：

rake aborted!
LoadError: dlopen(/Users/macbook/.rbenv/versions/2.0.0-p247/lib/ruby/gems/2.0.0/bundler/gems/mysql2-a2800f86754b/lib/mysql2/mysql2.bundle, 9): Library not loaded: /usr/local/lib/libmysqlclient.18.dylib
Referenced from: /Users/macbook/.rbenv/versions/2.0.0-p247/lib/ruby/gems/2.0.0/bundler/gems/mysql2-a2800f86754b/lib/mysql2/mysql2.bundle
Reason: image not found - /Users/macbook/.rbenv/versions/2.0.0-p247/lib/ruby/gems/2.0.0/bundler/gems/mysql2-a2800f86754b/lib/mysql2/mysql2.bundle
/Users/macbook/Desktop/tutorial/billingleap2/moviestore/config/application.rb:7:in `<top (required)>'
/Users/macbook/Desktop/tutorial/billingleap2/moviestore/Rakefile:4:in `<top (required)>'

我也尝试 'brew install mysql' 并且它成功了，但是在 'rake db:create' 上，我收到了这个错误：

#<Mysql2::Error: Can't connect to local MySQL server through socket '/tmp/mysql.sock' (2)>
Couldn't create database for {"adapter"=>"mysql2", "encoding"=>"utf8", "pool"=>5, "username"=>"root", "password"=>nil, "host"=>"localhost", "database"=>"moviestore_development"}, {:charset=>"utf8", :collation=>"utf8_unicode_ci"}
(If you set the charset manually, make sure you have a matching collation)
#<Mysql2::Error: Can't connect to local MySQL server through socket '/tmp/mysql.sock' (2)>
Couldn't create database for {"adapter"=>"mysql2", "encoding"=>"utf8","pool"=>5, "username"=>"root", "password"=>nil, "host"=>"localhost", "database"=>"moviestore_test"}, {:charset=>"utf8", :collation=>"utf8_unicode_ci"}
(If you set the charset manually, make sure you have a matching collation)

然后我'brew卸载mysql'并且那个问题消失了，但现在我有了第一个。

尝试 'gem install mysql2 -v '0.3.19'' 也会挂起。

可能是什么问题？

Answer 1

当您使用捆绑器时，您必须解决第一个问题（为什么捆绑安装失败）并使用捆绑器安装 mysql2 gem。一定有一些 gem 依赖问题需要查看。

并且，您应该运行：bundle exec rake db:migrate，因为您正在使用 bundler 和 Gemfile 等，这将确保您的 rake 任务在当前项目的上下文中运行。

更新：1

如果您已经运行：bundle install 成功并成功安装了mysql2 gem，则尝试运行：

`bundle exec rake db:create`

如果这导致您出现指定的错误（这意味着您的 libmysqlclient 库由于某种原因未加载）：

rake aborted!
LoadError: dlopen(/Users/macbook/.rbenv/versions/2.0.0-p247/lib/ruby/gems/2.0.0/bundler/gems/mysql2-a2800f86754b/lib/mysql2/mysql2.bundle, 9): Library not loaded: /usr/local/lib/libmysqlclient.18.dylib
Referenced from: /Users/macbook/.rbenv/versions/2.0.0-p247/lib/ruby/gems/2.0.0/bundler/gems/mysql2-a2800f86754b/lib/mysql2/mysql2.bundle
Reason: image not found - /Users/macbook/.rbenv/versions/2.0.0-p247/lib/ruby/gems/2.0.0/bundler/gems/mysql2-a2800f86754b/lib/mysql2/mysql2.bundle
/Users/macbook/Desktop/tutorial/billingleap2/moviestore/config/application.rb:7:in `<top (required)>'
/Users/macbook/Desktop/tutorial/billingleap2/moviestore/Rakefile:4:in `<top (required)>'

那么你应该看看这个answer 和this one too，它们对类似问题有一些规定的解决方案。试试那些看看是否有效。

更新：2

所以，mysql gem 有一些开发依赖项，需要先安装在您的系统中，然后才能真正使用 mysql。执行以下操作：

sudo gem install mysql-server mysql-client
sudo gem install libmysql-ruby libmysqlclient-dev
sudo gem install mysql

然后再试一次：

bundle install

更新：3

首先，找到你的socket文件：

mysqladmin variables | grep socket

它会给你这样的东西：

| socket                                            | /tmp/mysql.sock

然后，在 config/database.yml 中添加一行：

development:
  adapter: mysql2
  host: localhost
  username: root
  password: xxxx
  database: xxxx
  socket: /tmp/mysql.sock