Getting ChannelException when adding Google cloud client library to Play 2.5

Question

Here is some of the stack trace

io.netty.channel.ChannelException: Unable to create Channel from class class io.netty.channel.socket.nio.NioServerSocketChan         


        

Answer 1

The version of netty that google-cloud uses conflicts with the version of netty that Play uses. This will exclude google-cloud's netty in favor of Play's.

libraryDependencies += ("com.google.cloud" % "google-cloud" % "0.3.0").excludeAll(ExclusionRule(organization = "io.netty"))

However if you try to use a feature which needs gRPC it'll fail. Details:

https://groups.google.com/forum/#!topic/play-framework/UUDZZRpAv3w https://github.com/playframework/netty-reactive-streams/pull/17

There are two solutions:

A. Downgrading google-cloud to 0.2.2 which you can do by renaming the artifact to gcloud-java:

"com.google.cloud" % "gcloud-java" % "0.2.2"

B. Downgrading Play back to 2.4.6