This is an example project that illustrates how to use Liquibase with Docker to delivery instantly accessible development database and provide iamage that could be used to deploy database changes in the controlled manner to the various environments.
The multi-stage Dockerfile in this project allows to create two Docker images:
- The development/test database image with preloaded data set
- The database deployment image
In both cases the same Liquibase changeset is used.
The docker file has three stages:
- The 'deploy' stage which adds to the image all necessary files to run the
liquibase updatecommand - The 'build' stage which spins the database instance, applies the changeset including the test_data context and backs up the database
- The final stage that again spins up the database and restores backup
It is important that when all the stages are invoked during build, the docker build command is running when DOCKER_BUILDKIT is enabled!! Otherwise, the data are not restored (for whatever reason)
In order to build a deployment image run the following command:
docker build -t test-db-deployment --target deploy .
To build the test database run the following command:
docker build -t test-db-deployment .
To apply the database changes to a specific environment run the test-db-deployment image. It requires three environment variables to be set:
| Name | Description |
|---|---|
| URL | Target database URL |
| USERNAME | Username allowing access to the target database |
| PASSWORD | Password allowing access to the target database |
Bear in mind that neither of these variables have default values, hence if they are not set container will just fail.
For example, you can run the database update using the following docker command (providing thar database host is db and database is testdb.
docker run --name database-update -e URL=jdbc:postgresql://db/testdb -e USERNAME=test -e PASSWORD=password test-db-deployment
Container starts, runs the liquibase update and quits. You can check the logs to confirm that update succeeded. Then just remove the container.
To start test database run the following command:
docker run --name test-database -e POSTGRES_PASSWORD=password -d test-db-deployment