从带有依赖关系的 jar-with-dependencies 阴影 jar 中获取未找到密钥“akka.version”的配置设置答案

【问题标题】：Getting No configuration setting found for key 'akka.version' from jar-with-dependencies shaded jar从带有依赖关系的 jar-with-dependencies 阴影 jar 中获取未找到密钥“akka.version”的配置设置
【发布时间】：2016-08-03 20:14:52
【问题描述】：

我使用了akka docs 中给出的 maven-shade-plugin，它创建了一个阴影 jar，maven build 的以下输出证明了这一点：

[INFO] --- maven-shade-plugin:2.4.2:shade (default) @ remoting.example ---
[INFO] Including com.typesafe.akka:akka-remote_2.11:jar:2.4.8 in the shaded jar.
[INFO] Including org.scala-lang:scala-library:jar:2.11.8 in the shaded jar.
[INFO] Including com.typesafe.akka:akka-protobuf_2.11:jar:2.4.8 in the shaded jar.
[INFO] Including io.netty:netty:jar:3.10.6.Final in the shaded jar.
[INFO] Including org.uncommons.maths:uncommons-maths:jar:1.2.2a in the shaded jar.
[INFO] Including com.typesafe.akka:akka-actor_2.11:jar:2.4.8 in the shaded jar.
[INFO] Including com.typesafe:config:jar:1.3.0 in the shaded jar.
[INFO] Including org.scala-lang.modules:scala-java8-compat_2.11:jar:0.7.0 in the shaded jar.
[INFO] Replacing original artifact with shaded artifact.
[INFO] Replacing /home/dschulze/src/java/akka/remoting.example/target/remoting.example-0.0.1-SNAPSHOT.jar with /home/dschulze/src/java/akka/remoting.example/target/remoting.example-0.0.1-SNAPSHOT-shaded.jar
[INFO] Dependency-reduced POM written at: /home/dschulze/src/java/akka/remoting.example/dependency-reduced-pom.xml

当我运行 jar-with-dependencies 我仍然得到

Exception in thread "main" com.typesafe.config.ConfigException$Missing: No configuration setting found for key 'akka.version'

我还尝试了其他几种我在网络上的各种帖子中找到的方法，但它们都没有创建一个有效的 jar-with-dependencies。如何创建一个使用 akka 的 jar-with-dependencies？

【问题讨论】：

试过-Dakka.version?
添加-Dakka.version 得到No configuration setting found for key 'akka.actor.provider'。所以看起来它只是将问题转移到下一个属性。您的方法是否记录在任何地方？我要像这样在命令行上覆盖多少属性？
看我的回答。我怀疑您需要在提供最低配置的类路径上提供 application.conf。
我的回答有帮助吗？如果是这样，你能成为一个好公民并接受吗？

标签： akka maven-shade-plugin jar-with-dependencies

【解决方案1】：

根据有关使用jar or bundle 的文档：

Akka 的配置方法在很大程度上依赖于每个模块/jar 都有自己的 reference.conf 文件的概念，所有这些都将被配置发现并加载。不幸的是，这也意味着如果您将多个 jar 放入/合并到同一个 jar 中，您还需要合并所有 reference.confs。否则所有默认值都将丢失，Akka 将无法运行。

您可以提供自定义application.conf，如here 所述：

akka {

  # Loggers to register at boot time (akka.event.Logging$DefaultLogger logs
  # to STDOUT)
  loggers = ["akka.event.slf4j.Slf4jLogger"]

  # Log level used by the configured loggers (see "loggers") as soon
  # as they have been started; before that, see "stdout-loglevel"
  # Options: OFF, ERROR, WARNING, INFO, DEBUG
  loglevel = "DEBUG"

  # Log level for the very basic logger activated during ActorSystem startup.
  # This logger prints the log messages to stdout (System.out).
  # Options: OFF, ERROR, WARNING, INFO, DEBUG
  stdout-loglevel = "DEBUG"

  # Filter of log events that is used by the LoggingAdapter before
  # publishing log events to the eventStream.
  logging-filter = "akka.event.slf4j.Slf4jLoggingFilter"

  actor {
    provider = "akka.cluster.ClusterActorRefProvider"

    default-dispatcher {
      # Throughput for default Dispatcher, set to 1 for as fair as possible
      throughput = 10
    }
  }

  remote {
    # The port clients should connect to. Default is 2552.
    netty.tcp.port = 4711
  }
}

这涵盖了它所抱怨的 akka.actor.provider 设置等。

【讨论】：

【解决方案2】：

在您使用 Akka 提供的插件设置时，应该有一个以 -allinone.jar 结尾的新 jar 可用。这个罐子是带阴影的罐子。

【讨论】：