如何使用 Guice DI 和 Slick 运行 ScalaTest?

How to run ScalaTest with Guice DI and Slick?

我不知道如何配置 GuiceApplicationBuilder,以便我能够加载需要注入 DatabaseConfigProvider 的控制器。

我想指定用于测试的替代 postgres 数据库,或内存数据库(如果可能的话)。

代码

class   User
extends MySpecs
with    OneAppPerTest
{
    override def newAppForTest( testData: TestData ) = new GuiceApplicationBuilder()
        // Somehow bind a database here, I guess?
        .build()

    "A test" should "test" in
    {
        val result = Application.instanceCache[api.controller.User]
            .apply( app )
            .list()( FakeRequest() )

        ...
    }
}

堆栈跟踪

[info] - should return an entity *** FAILED ***
[info]   com.google.inject.ConfigurationException: Guice configuration errors:
[info] 
[info] 1) No implementation for play.api.db.slick.DatabaseConfigProvider was bound.
[info]   while locating play.api.db.slick.DatabaseConfigProvider
[info]     for parameter 1 at api.controller.User.<init>(User.scala:22)
[info]   while locating api.controller.User
[info] 
[info] 1 error
[info]   at com.google.inject.internal.InjectorImpl.getProvider(InjectorImpl.java:1042)
[info]   at com.google.inject.internal.InjectorImpl.getProvider(InjectorImpl.java:1001)
[info]   at com.google.inject.internal.InjectorImpl.getInstance(InjectorImpl.java:1051)
[info]   at play.api.inject.guice.GuiceInjector.instanceOf(GuiceInjectorBuilder.scala:321)
[info]   at play.api.inject.guice.GuiceInjector.instanceOf(GuiceInjectorBuilder.scala:316)
[info]   at play.api.Application$$anonfun$instanceCache.apply(Application.scala:234)
[info]   at play.api.Application$$anonfun$instanceCache.apply(Application.scala:234)
[info]   at play.utils.InlineCache.fresh(InlineCache.scala:69)
[info]   at play.utils.InlineCache.apply(InlineCache.scala:55)
[info]   ...

您需要为您的 GuiceApplicationBuilder() 添加一个配置,然后一切都应该由 play 框架自动处理。这样的事情应该有所帮助:

val app = new GuiceApplicationBuilder()
        .configure(
            Configuration.from(
                Map(
                    "slick.dbs.YOURDBNAME.driver" -> "slick.driver.H2Driver$",
                    "slick.dbs.YOURDBNAME.db.driver" -> "org.h2.Driver",
                    "slick.dbs.YOURDBNAME.db.url" -> "jdbc:h2:mem:",

                    "slick.dbs.default.driver" -> "slick.driver.MySQLDriver$",
                    "slick.dbs.default.db.driver" -> "com.mysql.jdbc.Driver"
                )
            )
        )
        .in(Mode.Test)
        .build()

这种方法有一些设置,但最终结果是公平的。首先,通过扩展实现您自己的 GuiceApplicationLoader。看我的。为什么你自己的应用程序加载器?您可以为每个 Prod/Dev/Test 模式指定不同的 configs/modules - 以及不同的数据源。您的主 application.conf 不会配置数据源。相反,您会将其移动到特定于环境的配置中,这些配置无论如何都会被应用程序加载器与主配置合并。您的 dev.conf 将如下所示:

slick.dbs {
  default {
    driver = "slick.driver.PostgresDriver$",
    db {
      driver = "org.postgresql.Driver",
      url = "jdbc:postgresql://localhost:5432/dev",
      user = "postgres"
      password = "postgres"
    }
  }
}

现在的诀窍是对所有其他配置(数据库 url、驱动程序、凭据等会有所不同)。通过这样的设置,您的 evolutions 将应用于您的测试和开发数据库。您的 test.conf 可能如下所示:

slick.dbs {
  default {
    // in memory configuration
  }
}

在您的测试中,将 WithApplicationLoader 与您的自定义应用程序加载器一起使用,仅此而已。

@RunWith(classOf[JUnitRunner])
class ApplicationSpec extends Specification {

    "Application" should {

        "return text/html ok for home" in new WithApplicationLoader(new CustomApplicationLoader) {
          val home = route(FakeRequest(routes.ApplicationController.home())).get
          status(home) must equalTo(OK)
          contentType(home) must beSome.which(_ == "text/html")
        }

    }

}

在测试本身中,您可以访问 app: Application 值:

val service = app.injector.instanceOf(classOf[IService])