Database migration

Реализация

Собрать образ liquibase и запускать как initContainer.
При откате использовать последнюю версию и помимо helm rollback <release>, запускать job для отката до тега liquibase rollback --tag=$ROLLBACK_TAG.

$ docker run --rm \
    --network database-migration \
    romanowalex/liquibase-container:latest \
    rollback --tag=v3.0 \
    --url=jdbc:postgresql://postgres:5432/migration \
    --username=program \
    --password=test

Прямые и обратные операции

Операция	Revert
`CREATE TABLE (VIEW, INDEX, FUNCTION, TRIGGER, SEQUENCE)`	`DROP`
`ADD COLUMN`	`DROP COLUMN`
`ALTER COLUMN`	`ALTER COLUMN`
`ADD CONSTRAINT ...`	`DROP CONSTRAINT`
`ALTER ... RENAME TO ...`	`ALTER ... RENAME TO ...`
`DROP TABLE (VIEW, FUNCTION, TRIGGER, SEQUENCE)`	`CREATE`
`DROP COLUMN (NOT NULL)`	`ADD COLUMN, UPDATE ... SET ..., ALTER COLUMN SET NOT NULL`
`DROP CONSTRAINT`	`DELETE ...` (records, which not meet constraint), `CREATE CONSTRAINT`
`INSERT`	`DELETE` (can leave unmodified, if doesn’t affect process)
`UPDATE`	`UPDATE` (can leave unmodified, if doesn’t affect process)
`DELETE`, `TRUNCATE`	`INSERT` (if possible)

Тестовые данные

Запрос на получение версии сервиса

Request

```http request GET http://localhost:8080/api/v1/version

**Response**

```json
{
  "version": "${git.build.version}",
  "commit": "${git.commit.id.abbrev}",
  "time": "${git.commit.time}"
}

Запрос на получение данных из БД

Request

```http request GET http://localhost:8080/api/v1/users

**Response**

```json
[
  {
    "name": "${user.name}",
    "status": "${user.status}",
    "location": "${user.location}"
  }
]

Миграции

Тестирование в кластере k8s

# create local cluster
$ kind create cluster --config kind.yml
$ kubectl apply -f https://raw.githubusercontent.com/kubernetes/ingress-nginx/main/deploy/static/provider/kind/deploy.yaml

# install required repos
$ helm repo add romanow https://romanow.github.io/helm-charts/
$ helm repo update

# install postgres
$ helm install postgres romanow/postgres --values postgres/values.yaml

# install service
$ helm upgrade \
    migration-application \
    romanow/java-service \
    --values=k8s/migration-application/values.yaml \
    --set image.tag="$IMAGE_VERSION" \
    --set ingress.name=k8s \
    --set ingress.domain=romanow-alex.ru \
    --description "$IMAGE_VERSION" \
    --install \
    --wait

# rollback migration
$ helm install \
    --generate-name \
    romanow/common-job \
    --values=k8s/rollback-job/values.yaml \
    --set rollbackTag="$VERSION" \
    --wait

# rollback revision
$ helm rollback migration-application "$REVISION" --wait