How to write database-agnostic Play application and perform first-time database initialization?

Question

I\'m using Slick with a Play Framework 2.1 and I have some troubles.

Given the following entity...

package models

import scala.slick.driver.Postgres         


        

Answer 1

I was also trying to address this problem: the ability to switch databases between test and production. The idea of wrapping each table object in a trait was unappealing.

I am not trying to discuss the pros and cons of the cake pattern here, but I found another solution, for those who are interested.

Basically, make an object like this:

package mypackage
import scala.slick.driver.H2Driver
import scala.slick.driver.ExtendedProfile
import scala.slick.driver.PostgresDriver

object MovableDriver {
  val simple = profile.simple
  lazy val profile: ExtendedProfile = {
    sys.env.get("database") match {
      case Some("postgres") => PostgresDriver
      case _ => H2Driver
    }
  }
}

Obviously, you can do any decision logic you like here. It does not have to be based on system properties.

Now, instead of:

import scala.slick.driver.H2Driver.simple._

You can say

import mypackage.MovableDriver.simple._

UPDATE: A Slick 3.0 Version, courtesy of trent-ahrens:

package mypackage

import com.typesafe.config.ConfigFactory

import scala.slick.driver.{H2Driver, JdbcDriver, MySQLDriver}

object AgnosticDriver {
  val simple = profile.simple
  lazy val profile: JdbcDriver = {
    sys.env.get("DB_ENVIRONMENT") match {
      case Some(e) => ConfigFactory.load().getString(s"$e.slickDriver") match {
        case "scala.slick.driver.H2Driver" => H2Driver
        case "scala.slick.driver.MySQLDriver" => MySQLDriver
      }
      case _ => H2Driver
    }
  }
}