Add another user to MySQL in Kubernetes - mysql

Question

Here is my MySQL
apiVersion: apps/v1beta1
kind: Deployment
metadata:
name: abc-def-my-mysql
namespace: abc-sk-test
labels:
project: abc
ca: my
spec:
replicas: 1
template:
metadata:
labels:
app: abc-def-my-mysql
project: abc
ca: my
spec:
containers:
- name: mysql
image: mysql:5.6
args: ["--default-authentication-plugin=mysql_native_password", "--ignore-db-dir=lost+found"]
ports:
- containerPort: 3306
env:
- name: MYSQL_ROOT_PASSWORD
value: "root"
- name: MYSQL_DATABASE
value: "my_abc"
- name: MYSQL_USER
value: "test_user"
- name: MYSQL_PASSWORD
value: "12345"
volumeMounts:
- mountPath: /var/lib/mysql
name: abc-def-my-mysql-storage
volumes:
- name: abc-def-my-mysql-storage
persistentVolumeClaim:
claimName: abc-def-my-mysql-pvc
I would like to add another user to mysql so real users can connect to it. Instead of using "test_user". how can I add another user, is it like adding any other environment variable to the above config

Answer 1

Mount a "create user script" into container's /docker-entrypoint-initdb.d directory. it will be executed once, at first pod start.
apiVersion: extensions/v1beta1
kind: Pod
metadata:
name: mysql
spec:
containers:
- name: mysql
image: mysql
.....
env:
- name: MYSQL_ROOT_PASSWORD
value: "root"
.....
volumeMounts:
- name: mysql-initdb
mountPath: /docker-entrypoint-initdb.d
volumes:
- name: mysql-initdb
configMap:
name: initdb
---
apiVersion: v1
kind: ConfigMap
metadata:
name: initdb
data:
initdb.sql: |-
CREATE USER 'first_user'#'%' IDENTIFIED BY '111' ;
CREATE USER 'second_user'#'%' IDENTIFIED BY '222' ;
Test:
kubectl exec -it <PODNAME> -- mysql -uroot -p -e 'SELECT user, host FROM mysql.user;'
+-------------+------+
| user | host |
+-------------+------+
| first_user | % |
| second_user | % |
| root | % |
+-------------+------+
See Initializing a fresh instance Mysql Docker Hub image:
When a container is started for the first time, a new database with
the specified name will be created and initialized with the provided
configuration variables. Furthermore, it will execute files with
extensions .sh, .sql and .sql.gz that are found in
/docker-entrypoint-initdb.d. Files will be executed in alphabetical
order.
You can easily populate your mysql services by mounting a SQL
dump into that directory and provide custom images with contributed
data. SQL files will be imported by default to the database specified
by the MYSQL_DATABASE variable.

Answer 2

Depending on user life-cycle, you can create user either at container startup, either through MySQL's docker startup script, mounted at /docker-entrypoint-initdb.d, or you could do it at CLI, after the server has started.
With container startup script, you may have to take care of multiple containers running the same script, e.g. CREATE user if exists.
CLI option may be more suitable if the DB server is long lived, and you will get requests for multiple user creation even after server creation.