Jenkins java.io.NotSerializableException when running slave on AWS ECS - jenkins

Question

A weird problem I came across: I run my slave as a docker image, sometimes as docker container on master node and other times on ECS(Fargate) using Amazon Elastic Container Service plugin.
I run this below piece of code
publishLambda(
awsAccessKeyId:"${env.AWS_ACCESS_KEY_ID}",
awsSecretKey:"${env.AWS_SECRET_ACCESS_KEY}",
awsRegion:"${lambda_config.region}",
functionARN:lambda_name,
functionAlias:"DEV"
)
It works fine when I’m running the slave as docker container but when run on ECS, I get the following error after the lambda gets published successfully. I suspect its something with the hudson.remoting api when its trying to get a response across the network.
IMO hudson.remoting should be behaving the same irrespective of where the containers are running. How am i getting such discrepencies?
java.io.NotSerializableException:
com.xti.jenkins.plugin.awslambda.publish.LambdaPublishServiceResponse
at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1184)
at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
at hudson.remoting.UserRequest._serialize(UserRequest.java:264)
at hudson.remoting.UserRequest.serialize(UserRequest.java:273) Also: hudson.remoting.Channel$CallSiteStackTrace: Remote call to
JNLP4-connect connection from
ec2-18-224-68-207.us-east-2.compute.amazonaws.com/18.224.68.207:40038
at hudson.remoting.Channel.attachCallSiteStackTrace(Channel.java:1741)
at hudson.remoting.UserRequest$ExceptionResponse.retrieve(UserRequest.java:357)
at hudson.remoting.Channel.call(Channel.java:955)
at com.xti.jenkins.plugin.awslambda.publish.LambdaPublishBuildStep.perform(LambdaPublishBuildStep.java:58)
at com.xti.jenkins.plugin.awslambda.publish.LambdaPublishBuildStep.perform(LambdaPublishBuildStep.java:46)
at org.jenkinsci.plugins.workflow.steps.CoreStep$Execution.run(CoreStep.java:80)
at org.jenkinsci.plugins.workflow.steps.CoreStep$Execution.run(CoreStep.java:67)
at org.jenkinsci.plugins.workflow.steps.SynchronousNonBlockingStepExecution.lambda$start$0(SynchronousNonBlockingStepExecution.java:47)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
Caused: java.io.IOException: Unable to serialize
com.xti.jenkins.plugin.awslambda.publish.LambdaPublishServiceResponse#4ec0e00f
at hudson.remoting.UserRequest.serialize(UserRequest.java:275)
at hudson.remoting.UserRequest.perform(UserRequest.java:223)
at hudson.remoting.UserRequest.perform(UserRequest.java:54)
at hudson.remoting.Request$2.run(Request.java:369)
at hudson.remoting.InterceptingExecutorService$1.call(InterceptingExecutorService.java:72)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at hudson.remoting.Engine$1.lambda$newThread$0(Engine.java:93)
Caused: java.lang.RuntimeException
at com.xti.jenkins.plugin.awslambda.publish.LambdaPublishBuildStep.perform(LambdaPublishBuildStep.java:66)
at com.xti.jenkins.plugin.awslambda.publish.LambdaPublishBuildStep.perform(LambdaPublishBuildStep.java:46)
at org.jenkinsci.plugins.workflow.steps.CoreStep$Execution.run(CoreStep.java:80)
at org.jenkinsci.plugins.workflow.steps.CoreStep$Execution.run(CoreStep.java:67)
at org.jenkinsci.plugins.workflow.steps.SynchronousNonBlockingStepExecution.lambda$start$0(SynchronousNonBlockingStepExecution.java:47)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748) Finished: FAILURE

Answer 1

The reason for this was Class LambdaPublishServiceResponse in Amazon Elastic Container Service plugin was not inheriting java.io.Serializable.
And since java remoting over network from slave running on ECS(fargate) had to be serialized to be retrieved by master, this change had to be done. Have raised a PR https://github.com/XT-i/aws-lambda-jenkins-plugin/pull/100