我试图从我的 application.conf 文件中读取数据源,但是每次我运行我的服务器或尝试运行测试用例时,我都会收到一条错误消息,指出没有启动应用程序。
这是我正在尝试做的一个例子:
试图从我的 application.conf
读取属性的单元测试
class DbConfigWebUnitTest extends PlaySpec with OneAppPerSuite {
implicit override lazy val app: FakeApplication = FakeApplication(
additionalConfiguration = Map("db.test.url" -> "jdbc:postgresql://localhost:5432/suredbitswebtest",
"db.test.user" -> "postgres", "db.test.password" -> "postgres", "db.test.driver" -> "org.postgresql.Driver"))
val dbManagementWeb = new DbManagementWeb with DbConfigWeb with DbTestQualifier
"DbConfigWebTest" must {
"have the same username as what is defined in application.conf" in {
dbManagementWeb.username must be("postgres")
}
}
}
这是我的
DbConfigWeb
import play.api.Play.current
trait DbConfigWeb extends DbConfig { qualifier: DbQualifier =>
val url: String = current.configuration.getString(qualifier + ".url").get
val username: String = current.configuration.getString(qualifier + ".user").get
val password: String = current.configuration.getString(qualifier + ".password").get
val driver: String = current.configuration.getString(qualifier + ".driver").get
override def database: DatabaseDef = JdbcBackend.Database.forURL(url, username, password, null, driver)
override implicit val session = database createSession
}
trait DbQualifier {
val qualifier: String
}
trait DbProductionQualifier extends DbQualifier {
override val qualifier = "db.production"
}
trait DbTestQualifier extends DbQualifier {
override val qualifier = "db.test"
}
最后这是我的堆栈跟踪:
[suredbits-web] $ last test:test
[debug] Forking tests - parallelism = false
[debug] Create a single-thread test executor
[debug] Runner for sbt.FrameworkWrapper produced 0 initial tasks for 0 tests.
[debug] Runner for org.scalatest.tools.Framework produced 2 initial tasks for 2 tests.
[debug] Running TaskDef(com.suredbits.web.db.DbConfigWebUnitTest, sbt.ForkMain$SubclassFingerscan@48687c55, false, [SuiteSelector])
[error] Uncaught exception when running com.suredbits.web.db.DbConfigWebUnitTest: java.lang.RuntimeException: There is no started application
sbt.ForkMain$ForkError: There is no started application
at scala.sys.package$.error(package.scala:27)
at play.api.Play$$anonfun$current$1.apply(Play.scala:71)
at play.api.Play$$anonfun$current$1.apply(Play.scala:71)
at scala.Option.getOrElse(Option.scala:120)
at play.api.Play$.current(Play.scala:71)
at com.suredbits.web.db.DbConfigWeb$class.$init$(DbConfigWebProduction.scala:14)
at com.suredbits.web.db.DbConfigWebUnitTest$$anon$1.<init>(DbConfigWebUnitTest.scala:14)
at com.suredbits.web.db.DbConfigWebUnitTest.<init>(DbConfigWebUnitTest.scala:14)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
at java.lang.Class.newInstance(Class.java:379)
at org.scalatest.tools.Framework$ScalaTestTask.execute(Framework.scala:641)
at sbt.ForkMain$Run$2.call(ForkMain.java:294)
at sbt.ForkMain$Run$2.call(ForkMain.java:284)
at java.util.concurrent.FutureTask.run(FutureTask.java:262)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:745)
最佳答案
我认为关键问题是val
Scala 特征中的 s 在构建时初始化,这是在测试 Play 应用程序启动之前(大概它的生命周期与每个规范示例相关联。)您有几个解决方法:
DbConfigWeb
def
或者可能是 lazy val
DbConfigWeb
摘要 play.api.Application
从中提取配置值的字段(而不是使用 current
)并将其显式(假应用程序)传递给任何 DbManagementWeb
作为构造函数参数 这是一个简化版本,使用第一种方法(对我有用):
import play.api.Play.current
trait DbConfig
trait DbConfigWeb extends DbConfig {
self: DbQualifier =>
// Using defs instead of vals
def url: String = current.configuration.getString(qualifier + ".url").get
def username: String = current.configuration.getString(qualifier + ".user").get
def password: String = current.configuration.getString(qualifier + ".password").get
def driver: String = current.configuration.getString(qualifier + ".driver").get
}
trait DbQualifier {
val qualifier: String
}
trait DbTestQualifier extends DbQualifier {
override val qualifier = "db.test"
}
和规范:
import controllers.{DbConfigWeb, DbTestQualifier}
import org.scalatestplus.play.{OneAppPerSuite, PlaySpec}
import play.api.test.FakeApplication
class DbConfigTest extends PlaySpec with OneAppPerSuite {
implicit override lazy val app: FakeApplication = FakeApplication(
additionalConfiguration = Map("db.test.url" -> "jdbc:h2:mem:play",
"db.test.user" -> "sa", "db.test.password" -> "", "db.test.driver" -> "org.h2.Driver"))
val dbManagementWeb = new DbConfigWeb with DbTestQualifier
"DbConfigWebTest" must {
"have the same username as what is defined in application.conf" in {
dbManagementWeb.username must be("sa")
}
}
}
我个人更喜欢第二种方法,它保持应用程序状态明确传递而不是依赖于
play.api.Play.current
, 你不能 依赖总是被启动。您在评论中提到
lazy val
s 不适合您,但我只能推测某些调用链正在强制初始化:再次检查是否不是这种情况。还要注意
val
的初始化顺序s 可能很复杂,虽然有些人可能不同意,但坚持 def
是一个非常安全的赌注。 s 作为特征成员,除非您确定这是一些昂贵的操作(在这种情况下,惰性 val 可能是一种选择。)
关于从application.conf中获取数据源时,Scala Play没有启动应用程序,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/28387203/