I am trying to run the akka-sample-cluster-kubernetes-scala as it is recommended to deploy an Akka cluster on to minikube using akka-management-cluster-bootstrap. After run every step recommended on the README file I can see the pods running on my kubectl output:
$ kubectl get pods
NAME READY STATUS RESTARTS AGE
appka-8b88f7bdd-485nx 1/1 Running 0 48m
appka-8b88f7bdd-4blrv 1/1 Running 0 48m
appka-8b88f7bdd-7qlc9 1/1 Running 0 48m
When I execute the ./scripts/test.sh it seems to fail on the last step:
"No 3 MemberUp log events found"
And I cannot connect to the given address said on the README file. The error:
$ curl http://127.0.0.1:8558/cluster/members/
curl: (7) Failed to connect to 127.0.0.1 port 8558: Connection refused
From now on I describe how I try to find the reason that I cannot use the sample akka + kubernetes project. I am trying to find the cause of the error above mentioned. I suppose I have to execute sbt run, even it is not mentioned on the sample project. And them I get the following error with respect to the ${REQUIRED_CONTACT_POINT_NR} variable at application.conf:
[error] Exception in thread "main" com.typesafe.config.ConfigException$UnresolvedSubstitution: application.conf @ jar:file:/home/felipe/workspace-idea/akka-sample-cluster-kubernetes-scala/target/bg-jobs/sbt_12a05599/job-1/target/d9ddd12d/64fe375d/akka-sample-cluster-kubernetes_2.13-0.0.0-70-49d6a855-20210104-1057.jar!/application.conf: 19: Could not resolve substitution to a value: ${REQUIRED_CONTACT_POINT_NR}
#management-config
akka.management {
cluster.bootstrap {
contact-point-discovery {
# pick the discovery method you'd like to use:
discovery-method = kubernetes-api
required-contact-point-nr = ${REQUIRED_CONTACT_POINT_NR}
}
}
}
#management-config
So, I suppose that it is not getting the configuration from the kubernetes/akka-cluster.yml file: name: REQUIRED_CONTACT_POINT_NR. Changing it to required-contact-point-nr = 3 or 4 I get the error:
[error] SLF4J: A number (4) of logging calls during the initialization phase have been intercepted and are
[error] SLF4J: now being replayed. These are subject to the filtering rules of the underlying logging system.
[error] SLF4J: See also http://www.slf4j.org/codes.html#replay
...
[info] [2021-01-04 11:00:57,373] [INFO] [akka.remote.RemoteActorRefProvider$RemotingTerminator] [] [appka-akka.actor.default-dispatcher-3] - Shutting down remote daemon. MDC: {akkaAddress=akka://appka@127.0.0.1:25520, sourceThread=appka-akka.remote.default-remote-dispatcher-9, akkaSource=akka://appka@127.0.0.1:25520/system/remoting-terminator, sourceActorSystem=appka, akkaTimestamp=10:00:57.373UTC}
[info] [2021-01-04 11:00:57,376] [INFO] [akka.remote.RemoteActorRefProvider$RemotingTerminator] [] [appka-akka.actor.default-dispatcher-3] - Remote daemon shut down; proceeding with flushing remote transports. MDC: {akkaAddress=akka://appka@127.0.0.1:25520, sourceThread=appka-akka.remote.default-remote-dispatcher-9, akkaSource=akka://appka@127.0.0.1:25520/system/remoting-terminator, sourceActorSystem=appka, akkaTimestamp=10:00:57.375UTC}
[info] [2021-01-04 11:00:57,414] [INFO] [akka.remote.RemoteActorRefProvider$RemotingTerminator] [] [appka-akka.actor.default-dispatcher-3] - Remoting shut down. MDC: {akkaAddress=akka://appka@127.0.0.1:25520, sourceThread=appka-akka.remote.default-remote-dispatcher-9, akkaSource=akka://appka@127.0.0.1:25520/system/remoting-terminator, sourceActorSystem=appka, akkaTimestamp=10:00:57.414UTC}
[error] Nonzero exit code returned from runner: 255
[error] (Compile / run) Nonzero exit code returned from runner: 255
[error] Total time: 6 s, completed Jan 4, 2021 11:00:57 AM
The answer and the comments on my questions are right. I don't need to run sbt run to visualize the output at the web browser. What I was missing is to port-forward the current port of the cluster nodes to the output port. This is not specified on the akka-sample-cluster-kubernetes-scala, but I believe that is because they run directly on the Google Kubernetes Engine platform and not inside minikube first.
$ kubectl get pods -A
NAMESPACE NAME READY STATUS RESTARTS AGE
appka-1 appka-8b88f7bdd-97zfl 1/1 Running 0 9m10s
appka-1 appka-8b88f7bdd-bhv44 1/1 Running 0 9m10s
appka-1 appka-8b88f7bdd-ff76s 1/1 Running 0 9m10s
$ #### THIS COMMAND IS NOT IN THE README FILE OF THE DEMO ####
$ kubectl port-forward appka-8b88f7bdd-ff76s 8080
Forwarding from 127.0.0.1:8080 -> 8080
Forwarding from [::1]:8080 -> 8080
now I can see the output:
$ http GET http://127.0.0.1:8080/
HTTP/1.1 200 OK
Content-Length: 11
Content-Type: text/plain; charset=UTF-8
Date: Wed, 06 Jan 2021 10:59:40 GMT
Server: akka-http/10.2.1
Hello world