错误详情:
An error occurred while installing mysql2 (0.3.20), and Bundler cannot continue.
Make sure that `gem install mysql2 -v '0.3.20' --source 'https://gems.ruby-china.com/'` succeeds before bundling.
In Gemfile:
mysql2
安装错误提示操作根本不起作用
原因:
缺少mysql-client和libmysqlclient-dev
正确做法:
$ sudo apt install mysql-client libmysqlclient-dev
以上这是ubuntu的操作,其他linux发行版请自行搜索相应软件包名。