Connecting to DSE Graph running on a Docker Container results into No host found - scala

Question

I am running my DSE Graph inside a Docker container with this command.
docker run -e DS_LICENSE=accept -p 9042:9042 --name my-dse -d datastax/dse-server -g -k -s
On my Scala Code I am referencing it as follows
object GrDbConnection {
val dseCluster = DseCluster.builder()
.addContactPoints("127.0.0.1").withPort(9042)
.build()
val graphName = "graphName"
val graphOptions = new GraphOptions()
.setGraphName(graphName)
var graph:ScalaGraph = null
try {
val session = dseCluster.connect()
// The following uses the DSE graph schema API, which is currently only supported by the string-based
// execution interface. Eventually there will be a programmatic API for making schema changes, but until
// then this needs to be used.
// Create graph
session.executeGraph("system.graph(name).ifNotExists().create()", ImmutableMap.of("name", graphName))
// Clear the schema to drop any existing data and schema
session.executeGraph(new SimpleGraphStatement("schema.clear()").setGraphName(graphName))
// Note: typically you would not want to use development mode and allow scans, but it is good for convenience
// and experimentation during development.
// Enable development mode and allow scans
session.executeGraph(new SimpleGraphStatement("schema.config().option('graph.schema_mode').set('development')")
.setGraphName(graphName))
session.executeGraph(new SimpleGraphStatement("schema.config().option('graph.allow_scan').set('true')")
.setGraphName(graphName))
// Create a ScalaGraph from a remote Traversal Source using withRemote
// See: http://tinkerpop.apache.org/docs/current/reference/#connecting-via-remotegraph for more details
val connection = DseRemoteConnection.builder(session)
.withGraphOptions(graphOptions)
.build()
graph = EmptyGraph.instance().asScala
.configure(_.withRemote(connection))
} finally {
dseCluster.close()
}
}
Then In one of my controllers I have used this to invoke a query to the DSE Graph.
def test = Action {
val r = GrDbConnection.graph.V().count()
print(r.iterate())
Ok
}
This returns an error
lay.api.http.HttpErrorHandlerExceptions$$anon$1: Execution exception[[NoHostAvailableException: All host(s) tried for query failed (no host was tried)]]
at play.api.http.HttpErrorHandlerExceptions$.throwableToUsefulException(HttpErrorHandler.scala:251)
at play.api.http.DefaultHttpErrorHandler.onServerError(HttpErrorHandler.scala:178)
at play.core.server.AkkaHttpServer$$anonfun$1.applyOrElse(AkkaHttpServer.scala:363)
at play.core.server.AkkaHttpServer$$anonfun$1.applyOrElse(AkkaHttpServer.scala:361)
at scala.concurrent.Future.$anonfun$recoverWith$1(Future.scala:413)
at scala.concurrent.impl.Promise.$anonfun$transformWith$1(Promise.scala:37)
at scala.concurrent.impl.CallbackRunnable.run(Promise.scala:60)
at akka.dispatch.BatchingExecutor$AbstractBatch.processBatch(BatchingExecutor.scala:55)
at akka.dispatch.BatchingExecutor$BlockableBatch.$anonfun$run$1(BatchingExecutor.scala:91)
at scala.runtime.java8.JFunction0$mcV$sp.apply(JFunction0$mcV$sp.java:12)
Caused by: com.datastax.driver.core.exceptions.NoHostAvailableException: All host(s) tried for query failed (no host was tried)
at com.datastax.driver.core.RequestHandler.reportNoMoreHosts(RequestHandler.java:221)
at com.datastax.driver.core.RequestHandler.access$1000(RequestHandler.java:41)
at com.datastax.driver.core.RequestHandler$SpeculativeExecution.findNextHostAndQuery(RequestHandler.java:292)
at com.datastax.driver.core.RequestHandler.startNewExecution(RequestHandler.java:109)
at com.datastax.driver.core.RequestHandler.sendRequest(RequestHandler.java:89)
at com.datastax.driver.core.SessionManager.executeAsync(SessionManager.java:124)
at com.datastax.driver.dse.DefaultDseSession.executeGraphAsync(DefaultDseSession.java:123)
at com.datastax.dse.graph.internal.DseRemoteConnection.submitAsync(DseRemoteConnection.java:74)
at org.apache.tinkerpop.gremlin.process.remote.traversal.step.map.RemoteStep.promise(RemoteStep.java:89)
at org.apache.tinkerpop.gremlin.process.remote.traversal.step.map.RemoteStep.processNextStart(RemoteStep.java:65)

Answer 1

Turns out all I needed to do was to remove
finally {
dseCluster.close()
}