3.2GORM

3.3Additional configuration

4GraalVM support

5Events

6Endpoint

7Repository

Micronaut Flyway

Integration between Micronaut and Flyway

Version:

1 Introduction

To use the Micronaut’s integration with Flyway you must have the micronaut-flyway dependency on your classpath:

implementation("io.micronaut.flyway:micronaut-flyway")

<dependency>
    <groupId>io.micronaut.flyway</groupId>
    <artifactId>micronaut-flyway</artifactId>
</dependency>

2 Release History

For this project, you can find a list of releases (with release notes) here:

https://github.com/micronaut-projects/micronaut-flyway/releases

3 Configuration

3.1 JPA/Hibernate

You can define Flyway configuration for each datasource. The following example demonstrates using it:

src/main/resources/application.yml

datasources:
  default: (3)
    url: 'jdbc:h2:mem:flywayDb;DB_CLOSE_DELAY=-1;DB_CLOSE_ON_EXIT=FALSE'
    username: 'sa'
    password: ''
    driverClassName: 'org.h2.Driver'
jpa:
  default: (3)
    packages-to-scan:
      - 'example.micronaut'
    properties:
      hibernate:
        hbm2ddl:
          auto: none (1)
        show_sql: true
flyway:
  datasources: (2)
    default: (3)
      enabled: true (4)

1	Disable schema DDL creation.
2	Define flyway configuration under `flyway.datasources` key.
3	Configure flyway configuration for `default` datasource.
4	Enable the flyway migrations for the `default` datasource.

You need to put the migrations in Flyway default directory src/main/resources/db/migration. If you want to modify the default directory or add more, you need to set the property flyway.datasources.default.locations. For example:

flyway:
  datasources:
    default:
      enabled: true
      locations:
        - classpath:databasemigrations (1)
        - classpath:other (1)

1	This will configure Flyway to look for migrations in the directories `src/main/resources/databasemigrations` and `src/main/resources/other`.

Now, in the migration directory you can include your migrations:

src/main/resources/db/migration/V1__create-books-schema.sql

create table books (
  id int not null primary key,
  name varchar(255) not null,
  constraint id unique (id),
  constraint name unique (name),
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

Starting with Micronaut 1.1.3 it is not necessary to define the jpa configuration if you only want to run the migrations but not actually use JPA.

3.2 GORM

There is also support for running Flyway migrations when using GORM.

1.- Add the dependency:

implementation("io.micronaut.configuration:micronaut-hibernate-gorm")

<dependency>
    <groupId>io.micronaut.configuration</groupId>
    <artifactId>micronaut-hibernate-gorm</artifactId>
</dependency>

2.- You also need at least one class annotated with @grails.gorm.annotation.Entity to trigger the migrations.

src/main/groovy/example/Book.groovy

import grails.gorm.annotation.Entity

@Entity
class Book {
    String name
}

3.- Then it is necessary to configure GORM datasource:

src/main/resources/application.yml

dataSource: (1)
  pooled: true
  jmxExport: true
  dbCreate: none (2)
  url: 'jdbc:h2:mem:GORMDb'
  driverClassName: org.h2.Driver
  username: sa
  password: ''

flyway:
  datasources: (3)
    default: (4)
      enabled: true (5)

1	Definition of the first data source in GORM. The name it’s `default` and it can’t be changed.
2	Disable schema DDL creation.
3	Define flyway configuration under `flyway.datasources` key.
4	Define flyway configuration for the `default` datasource.
5	Enable the flyway migrations for the `default` datasource.

Multiple Data sources

It is also possible to configure Flyway migrations with multiple data sources when using GORM:

src/main/resources/application.yml

dataSource: (1)
  pooled: true
  jmxExport: true
  dbCreate: none
  url: 'jdbc:h2:mem:flywayGORMDb'
  driverClassName: org.h2.Driver
  username: sa
  password: ''

dataSources:
  books: (2)
    pooled: true
    jmxExport: true
    dbCreate: none
    url: 'jdbc:h2:mem:flywayBooksDb'
    driverClassName: org.h2.Driver
    username: sa
    password: ''

flyway:
  datasources:
    default: (3)
      enabled: true
    books: (4)
      enabled: true

1	Definition of the first data source in GORM. The name it’s `default` and it can’t be changed.
2	Name of the additional data source.
3	Enable the flyway migrations for the `books` datasource.
4	Enable the flyway migrations for the `default` datasource.

For more information about how to configure GORM, take a look at the documentation.

3.3 Additional configuration

There are several options available for configuration:

🔗

Table 1. Configuration Properties for FlywayConfigurationProperties
Property	Type	Description
`flyway.datasources.*.configuration`	org.flywaydb.core.api.configuration.Configuration
`flyway.datasources.*.dry-run-output`	java.io.OutputStream
`flyway.datasources.*.error-overrides`	java.lang.String[]
`flyway.datasources.*.group`	boolean
`flyway.datasources.*.installed-by`	java.lang.String
`flyway.datasources.*.mixed`	boolean
`flyway.datasources.*.ignore-missing-migrations`	boolean
`flyway.datasources.*.ignore-ignored-migrations`	boolean
`flyway.datasources.*.ignore-pending-migrations`	boolean
`flyway.datasources.*.ignore-future-migrations`	boolean
`flyway.datasources.*.validate-migration-naming`	boolean
`flyway.datasources.*.validate-on-migrate`	boolean
`flyway.datasources.*.clean-on-validation-error`	boolean
`flyway.datasources.*.clean-disabled`	boolean
`flyway.datasources.*.encoding`	java.lang.String
`flyway.datasources.*.default-schema`	java.lang.String
`flyway.datasources.*.schemas`	java.lang.String[]
`flyway.datasources.*.table`	java.lang.String
`flyway.datasources.*.tablespace`	java.lang.String
`flyway.datasources.*.target`	org.flywaydb.core.api.MigrationVersion
`flyway.datasources.*.placeholder-replacement`	boolean
`flyway.datasources.*.placeholders`	java.util.Map
`flyway.datasources.*.placeholder-prefix`	java.lang.String
`flyway.datasources.*.placeholder-suffix`	java.lang.String
`flyway.datasources.*.sql-migration-prefix`	java.lang.String
`flyway.datasources.*.undo-sql-migration-prefix`	java.lang.String
`flyway.datasources.*.repeatable-sql-migration-prefix`	java.lang.String
`flyway.datasources.*.sql-migration-separator`	java.lang.String
`flyway.datasources.*.sql-migration-suffixes`	java.lang.String[]
`flyway.datasources.*.java-migrations`	org.flywaydb.core.api.migration.JavaMigration[]
`flyway.datasources.*.data-source`	javax.sql.DataSource
`flyway.datasources.*.connect-retries`	int
`flyway.datasources.*.init-sql`	java.lang.String
`flyway.datasources.*.baseline-version`	org.flywaydb.core.api.MigrationVersion
`flyway.datasources.*.baseline-description`	java.lang.String
`flyway.datasources.*.baseline-on-migrate`	boolean
`flyway.datasources.*.out-of-order`	boolean
`flyway.datasources.*.callbacks`	org.flywaydb.core.api.callback.Callback[]
`flyway.datasources.*.skip-default-callbacks`	boolean
`flyway.datasources.*.resolvers`	org.flywaydb.core.api.resolver.MigrationResolver[]
`flyway.datasources.*.skip-default-resolvers`	boolean
`flyway.datasources.*.stream`	boolean
`flyway.datasources.*.batch`	boolean
`flyway.datasources.*.oracle-sqlplus`	boolean
`flyway.datasources.*.oracle-sqlplus-warn`	boolean
`flyway.datasources.*.license-key`	java.lang.String
`flyway.datasources.*.load-default-configuration-files`	java.lang.String
`flyway.datasources.*.enabled`	boolean	Set whether this flyway configuration is enabled. Default value (true).
`flyway.datasources.*.async`	boolean	Whether flyway migrations should run asynchronously.
`flyway.datasources.*.clean-schema`	boolean	Set whether Flyway will clean the schema before running the migrations. Default value (false).
`flyway.datasources.*.url`	java.lang.String	The JDBC url of the database to migrate
`flyway.datasources.*.user`	java.lang.String	The user of the database to migrate
`flyway.datasources.*.password`	java.lang.String	The password of the database to migrate
`flyway.datasources.*.username`	java.lang.String	The username of the database to migrate
`flyway.datasources.*.locations`	java.lang.String[]	The locations for the migrations

By default Micronaut will configure Flyway to use the datasources defined under datasources configuration key. If you want to use a different datasource you need to define the properties flyway.datasources.*.url, flyway.datasources.*.user and flyway.datasources.*.password.

4 GraalVM support

Micronaut Flyway is compatible with GraalVM so it is possible to create native images and run the migrations during application startup.

The list of migrations to run is precomputed during native image build time and by default Micronaut looks for migrations in the Flyway default directory src/main/resources/db/migration. If you want to change that directory or add more directories to look for migrations you need to add an additional parameter to native-image command.

For example, if you have the following configuration:

flyway:
  datasources:
    default:
      locations:
        - classpath:databasemigrations (1)
        - classpath:other (1)

1	Flyway will look for migrations in `src/main/resources/databasemigrations` and `src/main/resources/other`.

You need to use the parameter flyway.locations with a comma separated list of directories to look for:

native-image --no-server --no-fallback \
    --class-path build/libs/micronaut-flyway-graal-*-all.jar \
    -Dflyway.locations='classpath:databasemigrations,classpath:other' (1)

1	Define the locations to look for migrations.

See the section on GraalVM in the user guide for more information.

5 Events

Micronaut fires two different events when:

The schema has been cleaned: SchemaCleanedEvent.
The migrations have been executed: MigrationFinishedEvent.

6 Endpoint

This configuration also provides a built-in endpoint to expose all the applied migrations in /flyway.

To enable the endpoint add the following to the configuration:

resources/application.yml

endpoints:
  flyway:
    enabled: true (1)
    sensitive: false (2)

1	`/flyway` endpoint is enabled (this is the default).
2	`/flyway` endpoint is open for unauthenticated access.

$ curl http://localhost:8080/flyway

[{
    "name": "default",
    "migrations": [{
        "checksum": 1952043475,
        "installedOn": "2018-11-12T11:32:52.000+0000",
        "executionTime": 96,
        "installedRank": 1,
        "version": {
            "version": "1"
        },
        "description": "init",
        "installedBy": "root",
        "state": "SUCCESS",
        "type": "SQL",
        "script": "V1__init.sql"
    }, {
        "checksum": -1926058189,
        "installedOn": "2018-11-12T11:32:52.000+0000",
        "executionTime": 10,
        "installedRank": 2,
        "version": {
            "version": "2"
        },
        "description": "testdata",
        "installedBy": "root",
        "state": "SUCCESS",
        "type": "SQL",
        "script": "V2__testdata.sql"
    }]
}]

See the section on Built-in endpoints in the user guide for more information.

7 Repository

You can find the source code of this project in this repository:

https://github.com/micronaut-projects/micronaut-flyway

Table of Contents

Micronaut Flyway

1 Introduction

2 Release History

3 Configuration

3.1 JPA/Hibernate

3.2 GORM

Multiple Data sources

3.3 Additional configuration

4 GraalVM support

5 Events

6 Endpoint

7 Repository