Set up MySQL using Dockerfile - mysql

Question

I'm just getting started with Docker and was able to set up MySQL according to my needs, by running tutum/lamp and doing a bunch of exec. For example:
docker run -d -p 80:80 -p 3306:3306 --name test tutum/lamp
...
docker exec test mysqldump --host somehost --user someuser --password --databases somedatabase > dump.sql
docker exec test mysql -u root < dump.sql
However, I'm having issues converting this to a Dockerfile. Specifically, the following results in ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock':
FROM tutum/lamp
EXPOSE 80 3306
...
RUN mysqldump --host=$DB_IP --user=$DB_USER --password=$DB_PASSWORD --databases somedatabase > dump.sql
RUN mysql -u root < dump.sql

Answer 1

You will need to override run.sh in order to do that, because when you run a container it will install mysql for the first time.
That is why you can not connect to mysql prior to that (in my previous answer I wasn't aware of that).
I've managed to execute mysql command by adding this to Dockerfile
FROM tutum/lamp
ADD . /custom
RUN chmod 755 /custom/run.sh
CMD ["/custom/run.sh"]
Then in the same folder create a file run.sh
#!/bin/bash
VOLUME_HOME="/var/lib/mysql"
sed -ri -e "s/^upload_max_filesize.*/upload_max_filesize = ${PHP_UPLOAD_MAX_FILESIZE}/" \
-e "s/^post_max_size.*/post_max_size = ${PHP_POST_MAX_SIZE}/" /etc/php5/apache2/php.ini
if [[ ! -d $VOLUME_HOME/mysql ]]; then
echo "=> An empty or uninitialized MySQL volume is detected in $VOLUME_HOME"
echo "=> Installing MySQL ..."
mysql_install_db > /dev/null 2>&1
echo "=> Done!"
/create_mysql_admin_user.sh
else
echo "=> Using an existing volume of MySQL"
fi
( sleep 20 ; mysql -u root < /custom/dump.sql ; echo "*** IMPORT ***" ) &
exec supervisord -n
This file is the same as /run.sh with one line added to run sql import after 20 seconds to make sure mysql service is up and running (there must be more elegant way to run a command just after mysql is started, of course).