mysqlで問題が起きてしまい、動かない状態になってます。 質問

Question

railsのmysqlを5.7から8.0に上げてから、mysqlが使えなくなってしまいました。結局mysqlを下げたのですが、まだ使えない状態になっています。もしわかる方がいらしたら、教えていただきたいです。

$ mysql --version
mysql Ver 14.14 Distrib 5.7.24, for osx10.12 (x86_64) using EditLine wrapper

source 'https://rubygems.org'

# Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
gem 'rails', '4.2.8'
# Use mysql as the database for Active Record
gem 'mysql2', '0.3.18'
# Use SCSS for stylesheets
gem 'sass-rails', '~> 4.0.2'
# Use Uglifier as compressor for JavaScript assets
gem 'uglifier', '>= 1.3.0'
# Use CoffeeScript for .coffee assets and views
gem 'coffee-rails', '~> 4.1.0'
# See https://github.com/rails/execjs#readme for more supported runtimes
# gem 'therubyracer', platforms: :ruby

# Use jquery as the JavaScript library
gem 'jquery-rails'
# Turbolinks makes following links in your web application faster. Read more: https://github.com/rails/turbolinks
gem 'turbolinks'
# Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder
gem 'jbuilder', '~> 2.0'
# bundle exec rake doc:rails generates the API under doc/api.
gem 'sdoc', '~> 0.4.0', group: :doc

# Use ActiveModel has_secure_password
# gem 'bcrypt', '~> 3.1.7'

# Use Unicorn as the app server
# gem 'unicorn'

# Use Capistrano for deployment
# gem 'capistrano-rails', group: :development

group :development, :test do
  # Call 'byebug' anywhere in the code to stop execution and get a debugger console
  gem 'byebug'
end

group :development do
  # Access an IRB console on exception pages or by using <%= console %> in views
  gem 'web-console', '~> 2.0'

  # Spring speeds up development by keeping your application running in the background. Read more: https://github.com/rails/spring
  gem 'spring'
end

gem 'pry-rails'
gem 'compass-rails','~> 2.0'
gem 'sprockets', '2.11.0'
#pagenation
gem 'kaminari'
#login_logout
gem 'devise'
gem 'paperclip'

#chat
gem 'websocket-rails'
gem 'faye-websocket', '0.10.0'
#image
gem 'carrierwave'
gem 'rmagick'
#date
gem 'momentjs-rails'
gem 'bootstrap3-datetimepicker-rails'

$ mysql.server start
   Starting MySQL
   SUCCESS! 
 /usr/local/Cellar/mysql@5.7/5.7.24/bin/mysqld_safe: line 144: /usr/local/var/mysql/ishiwatadohiroshi-no-MacBook-Air.local.err: Permission denied
cat: /usr/local/var/mysql/ishiwatadohiroshi-no-MacBook-Air.local.pid: Permission denied
rm: /usr/local/var/mysql/ishiwatadohiroshi-no-MacBook-Air.local.pid: Permission denied
2019-01-25T16:42:04.6NZ mysqld_safe Fatal error: Can't remove the pid file:
/usr/local/var/mysql/ishiwatadohiroshi-no-MacBook-Air.local.pid.
Please remove the file manually and start /usr/local/Cellar/mysql@5.7/5.7.24/bin/mysqld_safe again;
mysqld daemon not started
/usr/local/Cellar/mysql@5.7/5.7.24/bin/mysqld_safe: line 144: /usr/local/var/mysql/ishiwatadohiroshi-no-MacBook-Air.local.err: Permission denied

$ rails s

/Users/hiroshi/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/mysql2-0.3.18/lib/mysql2.rb:31:in `require': dlopen(/Users/hiroshi/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/mysql2-0.3.18/lib/mysql2/mysql2.bundle, 9): Library not loaded: /usr/local/opt/mysql/lib/libmysqlclient.20.dylib (LoadError)
  Referenced from: /Users/hiroshi/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/mysql2-0.3.18/lib/mysql2/mysql2.bundle
  Reason: image not found - /Users/hiroshi/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/mysql2-0.3.18/lib/mysql2/mysql2.bundle
	from /Users/hiroshi/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/mysql2-0.3.18/lib/mysql2.rb:31:in `<top (required)>'
	from /Users/hiroshi/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/bundler-1.17.1/lib/bundler/runtime.rb:81:in `require'
	from /Users/hiroshi/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/bundler-1.17.1/lib/bundler/runtime.rb:81:in `block (2 levels) in require'
	from /Users/hiroshi/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/bundler-1.17.1/lib/bundler/runtime.rb:76:in `each'
	from /Users/hiroshi/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/bundler-1.17.1/lib/bundler/runtime.rb:76:in `block in require'
	from /Users/hiroshi/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/bundler-1.17.1/lib/bundler/runtime.rb:65:in `each'
	from /Users/hiroshi/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/bundler-1.17.1/lib/bundler/runtime.rb:65:in `require'
	from /Users/hiroshi/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/bundler-1.17.1/lib/bundler.rb:114:in `require'
	from /Users/hiroshi/Desktop/sunny/config/application.rb:7:in `<top (required)>'
	from /Users/hiroshi/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/railties-4.2.8/lib/rails/commands/commands_tasks.rb:78:in `require'
	from /Users/hiroshi/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/railties-4.2.8/lib/rails/commands/commands_tasks.rb:78:in `block in server'
	from /Users/hiroshi/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/railties-4.2.8/lib/rails/commands/commands_tasks.rb:75:in `tap'
	from /Users/hiroshi/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/railties-4.2.8/lib/rails/commands/commands_tasks.rb:75:in `server'
	from /Users/hiroshi/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/railties-4.2.8/lib/rails/commands/commands_tasks.rb:39:in `run_command!'
	from /Users/hiroshi/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/railties-4.2.8/lib/rails/commands.rb:17:in `<top (required)>'
	from /Users/hiroshi/Desktop/sunny/bin/rails:9:in `require'
	from /Users/hiroshi/Desktop/sunny/bin/rails:9:in `<top (required)>'
	from /Users/hiroshi/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/spring-2.0.2/lib/spring/client/rails.rb:28:in `load'
	from /Users/hiroshi/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/spring-2.0.2/lib/spring/client/rails.rb:28:in `call'
	from /Users/hiroshi/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/spring-2.0.2/lib/spring/client/command.rb:7:in `call'
	from /Users/hiroshi/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/spring-2.0.2/lib/spring/client.rb:30:in `run'
	from /Users/hiroshi/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/spring-2.0.2/bin/spring:49:in `<top (required)>'
	from /Users/hiroshi/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/spring-2.0.2/lib/spring/binstub.rb:31:in `load'
	from /Users/hiroshi/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/spring-2.0.2/lib/spring/binstub.rb:31:in `<top (required)>'
	from /Users/hiroshi/.rbenv/versions/2.4.0/lib/ruby/2.4.0/rubygems/core_ext/kernel_require.rb:68:in `require'
	from /Users/hiroshi/.rbenv/versions/2.4.0/lib/ruby/2.4.0/rubygems/core_ext/kernel_require.rb:68:in `require'
	from /Users/hiroshi/Desktop/sunny/bin/spring:15:in `<top (required)>'
	from bin/rails:3:in `load'
	from bin/rails:3:in `<main>

Answer 1

mysql が起動しない問題は、/usr/local/var/mysql/ishi......pid を手動で消せば良いです。

Library not loaded: /usr/local/opt/mysql/lib/libmysqlclient.20.dylib の方は、
Qiita: Homebrew で MySQL を 5.7.22 から 8.0.11 にバージョンアップしたら Rails が動かなくなったので対処する

に同じ現象が載ってますが、
mysql のアップグレードの影響で libmysqlclient.*.dylib のバージョンが上がったようです。
gem mysql2 を uninstall して install すると解消されるようです。

mysql 自体は 5.7 に切り戻さなくても問題なかったかと思われます。

Comments

[avicii]

解決しました。ありがとうございます。

[set0gut1]

分からないですね…。
mysqlのバージョンを下げ直した時に何かしらファイルが残ってしまったのが原因な気がしますが。

不具合を回避する方法なら分かります。
mysqlを当初の予定通り8.0にアップグレードし、mysql2のuninstall→installです。

開発ってやればやるほど環境が汚れていくので、極力仮想マシン上でやった方がいいですよ。

[avicii]

仮想マシンっていうのはなんでしょうか？(未熟者ですみません。)

[set0gut1]

パソコンの中にパソコンを作り出す方式です。
macの上にlinuxを立て、そこで開発し、変になってきたら捨ててやり直します。
実務ではdockerがよく使われますが、難しいので、開発環境が欲しいだけならvirtualboxとかオススメです。

[avicii]

ありがとうございます。使ってみます！！