如何用Docker容器中的模式初始化MySQL数据库？

Question

FROM mysql
MAINTAINER  (me) <email>

# Copy the database schema to the /data directory
COPY files/epcis_schema.sql /data/epcis_schema.sql

# Change the working directory
WORKDIR data

CMD mysql -u $MYSQL_USER -p $MYSQL_PASSWORD $MYSQL_DATABASE < epcis_schema.sql

docker run --name ${CONTAINER_NAME} -e MYSQL_ROOT_PASSWORD=${DB_ROOT_PASSWORD} -e MYSQL_USER=${DB_USER} -e MYSQL_PASSWORD=${DB_USER_PASSWORD} -e MYSQL_DATABASE=${DB_NAME} -d mvpgomes/epcisdb

Answer 1

对于这个超长的回答，我很抱歉，但是，你还有一小段路要走才能到达你想要的地方。我要说的是，通常情况下，您不会将数据库的存储放在与数据库本身相同的容器中，您可以挂载一个主机卷，以便数据保持在docker主机上，或者可以使用一个容器来保存数据（/var/lib/mysql）。另外，我是一个新的mysql，所以，这可能不是超级高效的。上面说...

我想这里可能有几个问题。Dockerfile用于创建图像。您需要执行构建步骤。至少，您可以从包含Dockerfile的目录中执行以下操作：

docker build .

Dockerfile描述要创建的映像。我对mysql不太了解（我是postgres的粉丝），但是，我在网上搜索了一下“我如何初始化一个mysql docker容器”。首先，我创建了一个新的目录，将其命名为mdir，然后创建了一个files目录，并在其中存放了一个EPCIS_Schema.sql文件，该文件创建了一个数据库和一个表：

create database test;
use test;

CREATE TABLE testtab
(
id INTEGER AUTO_INCREMENT,
name TEXT,
PRIMARY KEY (id)
) COMMENT='this is my test table';

然后我在files目录中创建了一个名为init_db的脚本：

#!/bin/bash

# Initialize MySQL database.
# ADD this file into the container via Dockerfile.
# Assuming you specify a VOLUME ["/var/lib/mysql"] or `-v /var/lib/mysql` on the `docker run` command…
# Once built, do e.g. `docker run your_image /path/to/docker-mysql-initialize.sh`
# Again, make sure MySQL is persisting data outside the container for this to have any effect.

set -e
set -x

mysql_install_db

# Start the MySQL daemon in the background.
/usr/sbin/mysqld &
mysql_pid=$!

until mysqladmin ping >/dev/null 2>&1; do
  echo -n "."; sleep 0.2
done

# Permit root login without password from outside container.
mysql -e "GRANT ALL ON *.* TO root@'%' IDENTIFIED BY '' WITH GRANT OPTION"

# create the default database from the ADDed file.
mysql < /tmp/epcis_schema.sql

# Tell the MySQL daemon to shutdown.
mysqladmin shutdown

# Wait for the MySQL daemon to exit.
wait $mysql_pid

# create a tar file with the database as it currently exists
tar czvf default_mysql.tar.gz /var/lib/mysql

# the tarfile contains the initialized state of the database.
# when the container is started, if the database is empty (/var/lib/mysql)
# then it is unpacked from default_mysql.tar.gz from
# the ENTRYPOINT /tmp/run_db script

（此脚本的大部分内容是从以下位置提取的:https://gist.github.com/pda/9697520)

下面是我创建的files/run_db脚本：

# start db

set -e
set -x

# first, if the /var/lib/mysql directory is empty, unpack it from our predefined db
[ "$(ls -A /var/lib/mysql)" ] && echo "Running with existing database in /var/lib/mysql" || ( echo 'Populate initial db'; tar xpzvf default_mysql.tar.gz )

/usr/sbin/mysqld

FROM mysql
MAINTAINER  (me) <email>

# Copy the database schema to the /data directory
ADD files/run_db files/init_db files/epcis_schema.sql /tmp/

# init_db will create the default
# database from epcis_schema.sql, then
# stop mysqld, and finally copy the /var/lib/mysql directory
# to default_mysql_db.tar.gz
RUN /tmp/init_db

# run_db starts mysqld, but first it checks
# to see if the /var/lib/mysql directory is empty, if
# it is it is seeded with default_mysql_db.tar.gz before
# the mysql is fired up

ENTRYPOINT "/tmp/run_db"

docker build --no-cache .

Sending build context to Docker daemon 7.168 kB
Sending build context to Docker daemon 
Step 0 : FROM mysql
 ---> 461d07d927e6
Step 1 : MAINTAINER (me) <email>
 ---> Running in 963e8de55299
 ---> 2fd67c825c34
Removing intermediate container 963e8de55299
Step 2 : ADD files/run_db files/init_db files/epcis_schema.sql /tmp/
 ---> 81871189374b
Removing intermediate container 3221afd8695a
Step 3 : RUN /tmp/init_db
 ---> Running in 8dbdf74b2a79
+ mysql_install_db
2015-03-19 16:40:39 12 [Note] InnoDB: Using atomics to ref count buffer pool pages
...
/var/lib/mysql/ib_logfile0
 ---> 885ec2f1a7d5
Removing intermediate container 8dbdf74b2a79
Step 4 : ENTRYPOINT "/tmp/run_db"
 ---> Running in 717ed52ba665
 ---> 7f6d5215fe8d
Removing intermediate container 717ed52ba665
Successfully built 7f6d5215fe8d

docker run -d 7f6d5215fe8d

4b377ac7397ff5880bc9218abe6d7eadd49505d50efb5063d6fab796ee157bd3

然后我可以“停止”它，然后重新启动它。

docker stop 4b377
docker start 4b377

如果您查看日志,第一行将包含：

docker logs 4b377

Populate initial db
var/lib/mysql/
...

然后，在日志的末尾：

Running with existing database in /var/lib/mysql

gregs-air:~ gfausak$ ls -Rl mdir
total 8
-rw-r--r--  1 gfausak  wheel  534 Mar 19 11:13 Dockerfile
drwxr-xr-x  5 gfausak  staff  170 Mar 19 11:24 files

mdir/files:
total 24
-rw-r--r--  1 gfausak  staff   126 Mar 19 11:14 epcis_schema.sql
-rwxr-xr-x  1 gfausak  staff  1226 Mar 19 11:16 init_db
-rwxr-xr-x  1 gfausak  staff   284 Mar 19 11:23 run_db