ruby-on-rails - Rails 服务器无法运行——这是 mysql2 的问题吗？

Question

严格遵循教程并尝试让 Rails 服务器运行并出现以下错误:

NOTE: Gem.source_index is deprecated, use Specification. It will be removed on or after 2011-11-01.
    Gem.source_index called from /Library/Ruby/Gems/1.8/gems/bundler-1.0.10/lib/bundler/shared_helpers.rb:3.
    NOTE: Gem.source_index is deprecated, use Specification. It will be removed on or after 2011-11-01.
    Gem.source_index called from /Library/Ruby/Gems/1.8/gems/bundler-1.0.10/lib/bundler/source.rb:162.
    NOTE: Gem::SourceIndex#each is deprecated with no replacement. It will be removed on or after 2011-11-01.
    Gem::SourceIndex#each called from /Library/Ruby/Gems/1.8/gems/bundler-1.0.10/lib/bundler/source.rb:162.
    NOTE: Gem.source_index is deprecated, use Specification. It will be removed on or after 2011-11-01.
    Gem.source_index called from /Library/Ruby/Gems/1.8/gems/bundler-1.0.10/lib/bundler/shared_helpers.rb:84.
    /Library/Ruby/Gems/1.8/gems/mysql2-0.2.11/lib/mysql2/mysql2.bundle: dlopen(/Library/Ruby/Gems/1.8/gems/mysql2-0.2.11/lib/mysql2/mysql2.bundle, 9): Library not loaded: libmysqlclient.18.dylib (LoadError)
      Referenced from: /Library/Ruby/Gems/1.8/gems/mysql2-0.2.11/lib/mysql2/mysql2.bundle
      Reason: image not found - /Library/Ruby/Gems/1.8/gems/mysql2-0.2.11/lib/mysql2/mysql2.bundle
        from /Library/Ruby/Gems/1.8/gems/mysql2-0.2.11/lib/mysql2.rb:9
        from /Library/Ruby/Gems/1.8/gems/bundler-1.0.10/lib/bundler/runtime.rb:68:in `require'
        from /Library/Ruby/Gems/1.8/gems/bundler-1.0.10/lib/bundler/runtime.rb:68:in `require'
        from /Library/Ruby/Gems/1.8/gems/bundler-1.0.10/lib/bundler/runtime.rb:66:in `each'
        from /Library/Ruby/Gems/1.8/gems/bundler-1.0.10/lib/bundler/runtime.rb:66:in `require'
        from /Library/Ruby/Gems/1.8/gems/bundler-1.0.10/lib/bundler/runtime.rb:55:in `each'
        from /Library/Ruby/Gems/1.8/gems/bundler-1.0.10/lib/bundler/runtime.rb:55:in `require'
        from /Library/Ruby/Gems/1.8/gems/bundler-1.0.10/lib/bundler.rb:120:in `require'
        from /Users/EricFriedman/Sites/simple_cms/config/application.rb:7
        from /Library/Ruby/Gems/1.8/gems/railties-3.0.8/lib/rails/commands.rb:28:in `require'
        from /Library/Ruby/Gems/1.8/gems/railties-3.0.8/lib/rails/commands.rb:28
        from /Library/Ruby/Gems/1.8/gems/railties-3.0.8/lib/rails/commands.rb:27:in `tap'
        from /Library/Ruby/Gems/1.8/gems/railties-3.0.8/lib/rails/commands.rb:27
        from script/rails:6:in `require'
        from script/rails:6

Answer 1

如果您使用的是 Rails 3.0.x，则需要锁定您的 mysql2 版本。在你的 Gemfile 中:

gem "mysql2", "~> 0.2.11"

然后运行bundle install 或bundle update mysql2。

编辑:

我注意到您正在使用 0.2.11 版本的 mysql2 gem。

仔细观察，我注意到这个错误:

Library not loaded: libmysqlclient.18.dylib (LoadError)

这可能表明 mysql 开发头文件/库不可用。当您运行 bundle install 时，您安装 mysql2 gem 应该会失败。如果是这样，您需要安装这些开发库，然后重新安装 gem。