gregwhitaker / dbmigrator-example

Example for migrating rdbms data using a deployable Flyway wrapper.

dbmigrator

Utility for managing database migration scripts and versioning.

Project Structure

Migrations are stored in the following directories (please refer to the links below for more information):

• Flyway Script Migrations - Migration scripts both universal and environment-specific.
• Flyway Java Migrations - Java-based migrations.

Development

Common tasks for developing and testing migrations locally are detailed below:

Adding New Script Migration

Run the following command to create a new script migration:

./gradlew createMigrationScript --type="{migration type}" --ver="{version}" --desc="{description}"

Example:

./gradlew createMigrationScript --type="V" --ver="1.0.21" --desc="Add Table Foo"

The newly created script can be found in the script migration directory (src/main/resources/db/migration).

If you wish to create an environment-specific migration script, simply include the optional --env parameter:

./gradlew createMigrationScript --type="{migration type}" --ver="{version}" --desc="{description}" --env="{environment}"

Example:

./gradlew createMigrationScript --type="V" --ver="1.0.21" --desc="Add Table Foo" --env="test"

The newly created script can be found in the test script migration directory (src/main/resources/db/migration-env/test).

Adding New Java Migration

Run the following command to create a new Java migration:

./gradlew createMigrationClass --type="{migration type}" --ver="{version}" --desc="{description}"

Example:

./gradlew createMigrationClass --type="V" --ver="1.0.21" --desc="Add Table Foo"

The newly created class can be found in the java migration package (src/main/java/db/migration).

Building

Run the following command to build the application:

./gradlew clean build

Run the following command to build the application as a Docker image (Executable Jar):

./gradlew clean buildImage

Run the following command to build the application as a Docker image (Spring Boot):

./gradlew clean buildBootImage

Running Migrations Locally

The project is configured to use Docker Compose for testing migrations locally and there are a number of Gradle tasks provided to make the task easy.

Migrate Database

Run the following command to execute the database migration:

./gradlew migrateDb

Delete Database

Run the following command to delete the database:

./gradlew cleanDb

Delete Database and Run Migration

Run the following command to delete the database and rerun the migration:

./gradlew cleanMigrateDb

Delete Database and Mounted Data Volumes

The MySQL container makes use of volumes to store data across container invocations. Run the following command to delete the database, the associated data volumes, and start with a fresh instance:

./gradlew killDb

Integration Testing

The project contains a set of integration tests for validating the database schema post migration. Run the following command to execute the integration tasks locally:

./gradlew clean build integrationTest

For more information on adding integration tests, please refer to the Integration Test Documentation.