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# Overview
mysql for Kubernetes
# Usage
You must specify key configuration attributes when deploying,
or else arbitary defaults will be used. The attributes which
should be set are:
- user
- password
- database
- root_password
eg
$ juju deploy mysql \
--config user=fred \
--config password=secret \
--config database=test \
--config root_password=admin
These values may also be in a config.yaml file, eg
$ juju deploy mysql --config config.yaml
## Actions
### Backup
Execute the following steps to do a backup.
```bash
$ juju run-action mariadb-k8s/0 backup --wait
unit-mariadb-k8s-0:
UnitId: mariadb-k8s/0
id: "1"
results:
copy:
cmd: kubectl cp zaza-9769f2bf245e/mariadb-k8s-0:/var/lib/mysql/backup.sql.gz
backup.sql.gz
restore:
cmd: kubectl cp backup.sql.gz zaza-9769f2bf245e/mariadb-k8s-0:/var/lib/mysql/backup.sql.gz
juju: juju run-action mariadb-k8s/0 restore --wait
status: completed
timing:
completed: 2020-02-27 14:16:09 +0000 UTC
enqueued: 2020-02-27 14:16:08 +0000 UTC
started: 2020-02-27 14:16:09 +0000 UTC
$ kubectl cp zaza-9769f2bf245e/mariadb-k8s-0:/var/lib/mysql/backup.sql.gz backup.sql.gz
```
> Additional note: You can add `--string-args target=PRIMARY|SECONDARY` if you want this action to be run in a specific mongo unit. If `SECONDARY` is set, but the mongo unit isn't the `SECONDARY`, the action will fail.
### Restore
When the backup function is executed, you will see the commands you need to execute for restoring from a backup.
```bash
$ kubectl cp backup.sql.gz zaza-9769f2bf245e/mariadb-k8s-0:/var/lib/mysql/backup.sql.gz
$ juju run-action mariadb-k8s/0 restore --wait
unit-mariadb-k8s-0:
UnitId: mariadb-k8s/0
id: "2"
results:
message: Backup restored successfully
status: completed
timing:
completed: 2020-02-27 14:18:17 +0000 UTC
enqueued: 2020-02-27 14:18:07 +0000 UTC
started: 2020-02-27 14:18:11 +0000 UTC
```
### Remove backup
When a backup is made, it is stored in the unit. To easily remove the backup, execute this action:
```bash
$ juju run-action mariadb-k8s/0 remove-backup --wait
unit-mariadb-k8s-0:
UnitId: mariadb-k8s/0
id: "3"
results:
Stdout: |
Backup successfully removed!
status: completed
timing:
completed: 2020-02-27 14:18:41 +0000 UTC
enqueued: 2020-02-27 14:18:36 +0000 UTC
started: 2020-02-27 14:18:41 +0000 UTC
```
## Backup remotely
If we want to perform a backup remotely, follow the next steps:
```bash
$ sudo apt install mariadb-client-10.1 -y
$ juju status mariadb-k8s
Model Controller Cloud/Region Version SLA Timestamp
zaza-9769f2bf245e microk8s-localhost microk8s/localhost 2.7.2 unsupported 15:20:42+01:00
App Version Status Scale Charm Store Rev OS Address Notes
mariadb-k8s rocks.canonical... active 2 mariadb-k8s local 0 kubernetes 10.152.183.109
Unit Workload Agent Address Ports Message
mariadb-k8s/0* active idle 10.1.31.185 3306/TCP,4444/TCP,4567/TCP,4568/TCP ready
mariadb-k8s/1 active idle 10.1.31.186 3306/TCP,4444/TCP,4567/TCP,4568/TCP ready
$ mysqldump -uroot -posm4u --single-transaction \
--databases database \
--host 10.152.183.109 \
--port 3306 | gzip > backup.sql.gz
$ gunzip -c backup.sql.gz | mysql -uroot -posm4u --host 10.152.183.109 --port 3306
```
> Note: The remote backups should be done for each database. If `--all-databases` is step, when restoring from a database, you will see this error: `ERROR 1556 (HY000) at line 825: You can't use locks with log tables`
## Testing
The tests of this charm are done using tox and Zaza.
### Prepare environment
The machine in which the tests are run needs access to a juju k8s controller. The easiest way to approach this is by executing the following commands:
```bash
sudo apt install tox -y
sudo snap install microk8s --classic
sudo snap install juju
microk8s.status --wait-ready
microk8s.enable storage dns
juju bootstrap microk8s k8s-cloud
```
### Test charm with Tox
```bash
tox -e black # Check syntax
tox -e build # Build the charm
tox -e func # Test charm
```