Flyway

Enables you to configure and run Flyway commands from your mill build file. The flyway module currently supports the most common flyway use cases with file based migrations.

Configure flyway by overriding settings in your module. For example

build.mill

//| mvnDeps: ["com.lihaoyi::mill-contrib-flyway:$MILL_VERSION"]
package build

import mill.*, scalalib.*

import contrib.flyway.FlywayModule

object foo extends ScalaModule with FlywayModule {
  def scalaVersion = "2.12.8"

  //region flyway
  def flywayUrl = "jdbc:postgresql:myDb" // required
  def flywayDriverDeps = Seq(mvn"org.postgresql:postgresql:42.2.5") // JDBC driver
  def flywayPluginDeps = Seq(mvn"org.flywaydb:flyway-database-postgresql:<flyway-core-version>") // required for PostgreSQL
  def flywayUser = "postgres" // optional
  def flywayPlaceholders = Task {
    Map(
      "org" -> "mill"
    )
  } // optional
  // def flywayPassword = "" // optional
  //endregion
}

Flyway will look for migration files in db/migration in all resources folders by default. This should work regardless of if you are using a mill or sbt project layout.

You can then run common flyway commands like

> mill foo.flywayClean
> mill foo.flywayInfo
> mill foo.flywayMigrate

Set flywayDriverDeps to your JDBC driver dependency. If your database requires an external Flyway plugin (for example PostgreSQL or MySQL in Flyway 11+), set flywayPluginDeps to the matching Flyway database plugin dependency. Use the same version as the bundled flyway-core dependency.

You should never hard-code credentials or check them into a version control system. You should write some code to populate the settings for flyway instead. For example def flywayPassword = Task.Input(Task.ctx.env("FLYWAY_PASSWORD"))