【发布时间】：2014-05-07 02:06:30
【问题描述】：
我正在尝试使用mysql2 0.3.15 创建一个新的 Rails 4.1 项目并获得以下错误和堆栈跟踪。当我强制mysql2 0.3.14 时没有错误。
$ rake db:migrate
rake aborted!
TypeError: can't convert nil into String
/usr/local/Cellar/Gems/1.9/gems/mysql2-0.3.15/lib/mysql2/client.rb:67:in `connect'
/usr/local/Cellar/Gems/1.9/gems/mysql2-0.3.15/lib/mysql2/client.rb:67:in `initialize'
/usr/local/Cellar/Gems/1.9/gems/activerecord-4.1.0/lib/active_record/connection_adapters/mysql2_adapter.rb:18:in `new'
/usr/local/Cellar/Gems/1.9/gems/activerecord-4.1.0/lib/active_record/connection_adapters/mysql2_adapter.rb:18:in `mysql2_connection'
/usr/local/Cellar/Gems/1.9/gems/activerecord-4.1.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:435:in `new_connection'
/usr/local/Cellar/Gems/1.9/gems/activerecord-4.1.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:445:in `checkout_new_connection'
/usr/local/Cellar/Gems/1.9/gems/activerecord-4.1.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:416:in `acquire_connection'
/usr/local/Cellar/Gems/1.9/gems/activerecord-4.1.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:351:in `block in checkout'
/usr/local/Cellar/Gems/1.9/gems/activerecord-4.1.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:350:in `checkout'
/usr/local/Cellar/Gems/1.9/gems/activerecord-4.1.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:265:in `block in connection'
/usr/local/Cellar/Gems/1.9/gems/activerecord-4.1.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:264:in `connection'
/usr/local/Cellar/Gems/1.9/gems/activerecord-4.1.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:541:in `retrieve_connection'
/usr/local/Cellar/Gems/1.9/gems/activerecord-4.1.0/lib/active_record/connection_handling.rb:113:in `retrieve_connection'
/usr/local/Cellar/Gems/1.9/gems/activerecord-4.1.0/lib/active_record/connection_handling.rb:87:in `connection'
/usr/local/Cellar/Gems/1.9/gems/activerecord-4.1.0/lib/active_record/migration.rb:910:in `initialize'
/usr/local/Cellar/Gems/1.9/gems/activerecord-4.1.0/lib/active_record/migration.rb:807:in `new'
/usr/local/Cellar/Gems/1.9/gems/activerecord-4.1.0/lib/active_record/migration.rb:807:in `up'
/usr/local/Cellar/Gems/1.9/gems/activerecord-4.1.0/lib/active_record/migration.rb:785:in `migrate'
/usr/local/Cellar/Gems/1.9/gems/activerecord-4.1.0/lib/active_record/railties/databases.rake:34:in `block (2 levels) in <top (required)>'
这是我的database.yml 文件
default: &default
adapter: mysql2
encoding: utf8
pool: 5
username: root
password: "asdf"
timeout: 5000
development:
<<: *default
database: dev
socket: /tmp/mysql.sock
production:
<<: *default
database: prod
socket: /var/lib/mysql/mysql.sock
我的 MySQL 客户端库在 OSX 10.9.2 上是 5.6.16
更新
如果我在我的database.yml 文件中指定password、host 和port，此错误就会消失。现在出于某种原因需要这些吗？
【问题讨论】：
-
通常表示驱动程序期望的某处缺少或无效的字符串变量。问题可能不在 database.yml 中，而是在其他驱动程序或环境配置文件之一（即您设置 mySQL 的位置）。不是同一个问题，但相关github.com/datamapper/dm-core/issues/183
-
有什么理由让它可以与 mysql2 0.3.14 一起使用吗？我查看了标签的差异，但没有什么真正突出github.com/brianmario/mysql2/compare/0.3.14...0.3.15
-
rails 4.1.1的错误仍然存在 -
安装 gem 时，您是否给它提供了数据库的位置，并且您是否验证了新安装的版本是否正确？我想知道这是否真的是一个套接字问题 - 您是否验证过 /tmp/mysql.sock 文件存在？如果您指定的主机名不是 localhost（甚至是 127.0.0.1），它将尝试以 TCP 模式连接，而不是使用本地套接字。设置主机可能会覆盖对套接字的需求并解决您的问题。注意：如果正确拾取套接字，则不会使用端口号
-
也不知道为什么你的密码有引号 - 没有它们也能工作吗？如果这些都不起作用并且您仍然有兴趣找到问题，您可以在更新中提供新版本的 database.yml 吗？
标签： ruby-on-rails mysql2 ruby-on-rails-4.1