Mysql2::Error Can't initialize character set utf8mb4 (path: /usr/share/mysql/charsets/)

Question

In my Rails 4.2 app I stumbled on strange issue. I had to switch mysql encoding to utf8mb4 (to allow Emoji in posts). I've updated MySql to 5.7, altered tabels etc. Updated database.yml with:

encoding: utf8mb4
collation: utf8mb4_unicode_ci

Everything worked on my local machine that runs mac OS.

On test server I've done same steps and configuration. But if I set

encoding: utf8mb4

in database.yml I get

Mysql2::Error Can't initialize character set utf8mb4 (path: /usr/share/mysql/charsets/)

Additional MySQL setup for mysql I've done in my.cnf on both machines:

innodb_file_format = Barracuda
innodb_large_prefix
innodb_file_per_table = 1

init_connect='SET collation_connection = utf8_unicode_ci'
init_connect='SET NAMES utf8mb4'
innodb_file_format_max = Barracuda
innodb_strict_mode = 1

character-set-client-handshake = FALSE
character-set-server = utf8mb4
collation-server = utf8mb4_unicode_ci

I can add emoji on test server but not through Rails app. On both machines I'm usign mysql2 version 0.3.21. What can cause this issue?

PS. Even I don't have it on my local I've added utf8mb4 to Index.xml on test machine, but it didn't helped.

Answer 1

Maybe this will help: RoR: application_controller.rb:

  def configure_charsets
    response.headers["Content-Type"] = "text/html; charset=UTF-8"
    suppress(ActiveRecord::StatementInvalid) do
      ActiveRecord::Base.connection.execute 'SET NAMES utf8mb4'
    end
  end