scala - 如何在自定义 sbt 任务中通过 application.conf 进行 Slick 配置？

Question

我想创建一个设置任务，该任务创建一个光滑的数据库模式。为此，我的项目中有一个如下所示的任务对象:

object CreateSchema {

    val instance = Database.forConfig("localDb")

    def main(args: Array[String]) {
        val createFuture = instance.run(createActions)
        ...
        Await.ready(createFuture, Duration.Inf)
    }

}

在我的 build.sbt我定义了一个任务:

lazy val createSchema = taskKey[Unit]("CREATE database schema")

fullRunTask(createSchema, Runtime, "sbt.CreateSchema")

当我运行 sbt createSchema 时，它会按预期执行从命令行。

然而，问题在于 application.conf似乎没有被考虑在内(我也尝试过不同的范围，如 Compile 或 Test )。结果，任务失败，原因是 com.typesafe.config.ConfigException$Missing: No configuration setting found for key 'localDb' .

如何解决此问题以便配置可用？

我在这里发现了很多关于使用 application.conf 的问题。内 build.sbt本身，但这不是我需要的。

Answer 1

我使用 SBT 0.13.8 和 Slick 3.0.0 设置了一个小演示，它按预期工作。 (即使没有修改“-Dconfig.resource”。)

文件

./build.sbt

name := "SO_20150915"

version := "1.0"

scalaVersion := "2.11.7"

libraryDependencies ++= Seq(
  "com.typesafe"                 % "config"                 % "1.3.0"                            withSources() withJavadoc(),
  "com.typesafe.slick"          %% "slick"                  % "3.0.0",
  "org.slf4j"                    % "slf4j-nop"              % "1.6.4",
  "com.h2database"               % "h2"                     % "1.3.175"
)

lazy val createSchema = taskKey[Unit]("CREATE database schema")

fullRunTask(createSchema, Runtime, "somefun.CallMe")

./project/build.properties

sbt.version = 0.13.8

./src/main/resources/reference.conf

hello {
  world = "buuh."
}

h2mem1 = {
  url = "jdbc:h2:mem:test1"
  driver = org.h2.Driver
  connectionPool = disabled
  keepAliveConnection = true
}

./src/main/scala/somefun/CallMe.scala

package somefun

import com.typesafe.config.Config
import com.typesafe.config.ConfigFactory
import slick.driver.H2Driver.api._

/**
 * SO_20150915
 * Created by martin on 15.09.15.
 */
object CallMe {
  def main(args: Array[String]) : Unit = {
    println("Hello")
    val settings = new Settings()

    println(s"Settings read from hello.world: ${settings.hw}" )

    val db = Database.forConfig("h2mem1")
    try {
      // ...
      println("Do something with your database.")
    } finally db.close
  }

}

class Settings(val config: Config) {

  // This verifies that the Config is sane and has our
  // reference config. Importantly, we specify the "di3"
  // path so we only validate settings that belong to this
  // library. Otherwise, we might throw mistaken errors about
  // settings we know nothing about.
  config.checkValid(ConfigFactory.defaultReference(), "hello")

  // This uses the standard default Config, if none is provided,
  // which simplifies apps willing to use the defaults
  def this() {
    this(ConfigFactory.load())
  }

  val hw = config.getString("hello.world")
} 

结果

如果正在运行 sbt createSchema从控制台我获得输出

[info] Loading project definition from /home/.../SO_20150915/project
[info] Set current project to SO_20150915 (in build file:/home/.../SO_20150915/)
[info] Running somefun.CallMe 
Hello
Settings read from hello.world: buuh.
Do something with your database.
[success] Total time: 1 s, completed 15.09.2015 10:42:20

想法

请确认这个未经修改的演示项目也适用于您。

然后尝试在演示项目中更改 SBT 版本，看看是否有什么改变。

或者，重新检查您的项目设置并尝试使用更高版本的 SBT。