Micronaut

Micronaut 4 and 5 are supported.

Command line

Migrax reads application.yml / application.properties and the environments in MICRONAUT_ENVIRONMENTS:

datasources:
  default:
    url: jdbc:postgresql://localhost:5432/shop
    username: shop
    password: ${DB_PASSWORD}
jpa:
  default:
    properties:
      hibernate:
        hbm2ddl:
          auto: none

DATASOURCES_DEFAULT_URL, DATASOURCES_DEFAULT_USERNAME and DATASOURCES_DEFAULT_PASSWORD work too. Without a default data source, Migrax uses the first one. Hibernate settings under jpa.default.properties.* are passed to Hibernate.

Change the starter's update

Projects created from the Micronaut starter set hbm2ddl.auto: update. Set it to none or validate; migrax doctor shows the exact line.

Naming

Project uses	Naming	Example: homepageURL
Micronaut Data (micronaut-data-hibernate-jpa)	micronaut	homepage_url
Micronaut Hibernate JPA without Micronaut Data	jpa	homepageURL

Micronaut Data converts names to snake_case with its own rule, which differs from other snake_case rules for names like myURL (my_url) or productSKU (product_sku). It also uses one shared hibernate_sequence for generated ids. Migrax matches both, and when Micronaut Data is on the classpath it uses Micronaut's own naming class.

Migrate at startup

<dependency>
  <groupId>org.migrax</groupId>
  <artifactId>migrax-micronaut</artifactId>
  <version>0.4.0</version>
</dependency>

Migrations run as soon as Micronaut creates the data source, before Hibernate starts, so hbm2ddl.auto: validate checks the migrated schema.

Setting	Default	Meaning
migrax.enabled	true	Apply migrations at startup
migrax.datasource	default	Data source to migrate
migrax.locations	db/migration	Migration folder on the classpath
migrax.java-package	db.migration	Package of JavaMigration classes
migrax.resume	false	Re-run a failed migration marked -- migrax:resume-safe
migrax.lock-timeout	0	How long to wait while another instance migrates, for example 2m when several start together
migrax.placeholders.<name>		Values for ${name} placeholders
migrax.schemas		Schemas to migrate one after another

Health check

With micronaut-management in the application, Migrax adds a migrax health indicator: UP when every migration is applied and none failed, was edited or is missing, DOWN otherwise, with the counts as details (/health).