使用Akka/Akka Streams/Akka HTTP时的Akka版本冲突

Question

libraryDependencies ++= Seq(
  "com.typesafe.akka" %% "akka-actor" % "2.5.4",
  "com.typesafe.akka" %% "akka-stream" % "2.5.4",
  "com.typesafe.akka" %% "akka-stream-testkit" % "2.5.4" % Test,
  "com.typesafe.akka" %% "akka-http" % "10.0.9",
  "com.typesafe.akka" %% "akka-http-core" % "10.0.9",
  "org.scalatest" %% "scalatest" % "3.0.1" % Test)

[warn] Found version conflict(s) in library dependencies; some are 
suspected to be binary incompatible:
[warn] 
[warn]  * com.typesafe.akka:akka-stream_2.12:2.5.4 is selected over 
2.4.19
[warn]      +- com.typesafe.akka:akka-http-core_2.12:10.0.9       
(depends on 2.4.19)
[warn]      +- com.werner.opttech:dependency-test_2.12:0.0.0      
(depends on 2.4.19)
[warn] 
[warn]  * com.typesafe.akka:akka-actor_2.12:2.5.4 is selected over 
2.4.19
[warn]      +- com.werner.opttech:dependency-test_2.12:0.0.0      
(depends on 2.5.4)
[warn]      +- com.typesafe.akka:akka-stream_2.12:2.5.4           
(depends on 2.5.4)
[warn]      +- com.typesafe.akka:akka-parsing_2.12:10.0.9         
(depends on 2.4.19)

关于如何解决此错误的建议，以便我可以使用最新版本的akka、akka streams和akka HTTP？谢了！

Answer 1

您的配置是正确的，因为它遵循了您提到的兼容性准则。我认为你把警告信息误解为错误；您使用的是这些库的2.5.4版本。仔细看一下这个片段：

[warn]  * com.typesafe.akka:akka-actor_2.12:2.5.4 is selected over 2.4.19

sbt实际上选择了Akka-actor库的2.5.4版本，而不是2.4.19版本。

此外，在sbt控制台中运行show update将输出以下内容：

[info]  com.typesafe.akka:akka-actor_2.12
[info]          - 2.5.4
[info]                  status: release
[info]                  publicationDate: Thu Aug 10 09:17:00 EDT 2017
....
[info]          - 2.4.19
[info]                  evicted: true
[info]                  evictedData: latest-revision