Make the mysql root username a configuration parameter

This allows users who connect to an external database to customise the
root username. Indeed, quite often the "root" username is reserved.

Close #328

CHANGELOG.md

@@ -2,6 +2,10 @@
 
 Note: Breaking changes between versions are indicated by "💥".
 
+## Unreleased
+
+- [Improvement] Make it possible to customize the MySQL root username, for connecting to external MySQL databases
+
 ## v3.12.5 (2020-05-20)
 
 - [Improvement] Upgrade Android app to v2.21.1 and enable many features, such as downloading videos to SD card. Thanks for the help @ejklock!

docs/configuration.rst

@@ -104,12 +104,14 @@ MySQL
 - ``ACTIVATE_MYSQL`` (default: ``true``)
 - ``MYSQL_HOST`` (default: ``"mysql"``)
 - ``MYSQL_PORT`` (default: ``3306``)
+- ``MYSQL_ROOT_USERNAME`` (default: ``"root"``)
 - ``MYSQL_ROOT_PASSWORD`` (default: randomly generated) Note that you are responsible for creating the root user if you are using a managed database.
 
 By default, a running Open edX platform deployed with Tutor includes all necessary 3rd-party services, such as MySQL, MongoDb, etc. But it's also possible to store data on a separate database, such as `Amazon RDS <https://aws.amazon.com/rds/>`_. For instance, to store data on an external MySQL database, set the following configuration::
 
     ACTIVATE_MYSQL: false
     MYSQL_HOST: yourhost
+    MYSQL_ROOT_USERNAME: <root user name>
     MYSQL_ROOT_PASSWORD: <root user password>
 
 Elasticsearch

tutor/templates/config.yml

@@ -64,6 +64,7 @@ OPENEDX_MYSQL_DATABASE: "openedx"
 OPENEDX_MYSQL_USERNAME: "openedx"
 MYSQL_HOST: "mysql"
 MYSQL_PORT: 3306
+MYSQL_ROOT_USERNAME: "root"
 NGINX_HTTP_PORT: 80
 NGINX_HTTPS_PORT: 443
 PLATFORM_NAME: "My Open edX"

tutor/templates/hooks/mysql/init

@@ -1,7 +1,7 @@
 echo "Initialising MySQL..."
 mysql_connection_max_attempts=10
 mysql_connection_attempt=0
-until mysql -u root --password="{{ MYSQL_ROOT_PASSWORD }}" --host "{{ MYSQL_HOST }}" --port {{ MYSQL_PORT }} -e 'exit'
+until mysql -u {{ MYSQL_ROOT_USERNAME }} --password="{{ MYSQL_ROOT_PASSWORD }}" --host "{{ MYSQL_HOST }}" --port {{ MYSQL_PORT }} -e 'exit'
 do
     mysql_connection_attempt=$(expr $mysql_connection_attempt + 1)
     echo "    [$mysql_connection_attempt/$mysql_connection_max_attempts] Waiting for MySQL service (this may take a while)..."
@@ -14,5 +14,5 @@ do
 done
 echo "MySQL is up and running"
 
-mysql -u root --password="{{ MYSQL_ROOT_PASSWORD }}" --host "{{ MYSQL_HOST }}" --port {{ MYSQL_PORT }} -e 'CREATE DATABASE IF NOT EXISTS {{ OPENEDX_MYSQL_DATABASE }};'
-mysql -u root --password="{{ MYSQL_ROOT_PASSWORD }}" --host "{{ MYSQL_HOST }}" --port {{ MYSQL_PORT }} -e 'GRANT ALL ON {{ OPENEDX_MYSQL_DATABASE }}.* TO "{{ OPENEDX_MYSQL_USERNAME }}"@"%" IDENTIFIED BY "{{ OPENEDX_MYSQL_PASSWORD }}";'
+mysql -u {{ MYSQL_ROOT_USERNAME }} --password="{{ MYSQL_ROOT_PASSWORD }}" --host "{{ MYSQL_HOST }}" --port {{ MYSQL_PORT }} -e 'CREATE DATABASE IF NOT EXISTS {{ OPENEDX_MYSQL_DATABASE }};'
+mysql -u {{ MYSQL_ROOT_USERNAME }} --password="{{ MYSQL_ROOT_PASSWORD }}" --host "{{ MYSQL_HOST }}" --port {{ MYSQL_PORT }} -e 'GRANT ALL ON {{ OPENEDX_MYSQL_DATABASE }}.* TO "{{ OPENEDX_MYSQL_USERNAME }}"@"%" IDENTIFIED BY "{{ OPENEDX_MYSQL_PASSWORD }}";'