Im trying to test Cassandra Sink with use of TestContainers in a simple Flink pipeline which use DataStreamTestBase for tests:
public class CassandraPojoSinkExampleTest extends DataStreamTestBase {
@Rule
public CassandraContainer cassandra = new CassandraContainer<>().withInitScript("testInit3.cql")
.withCreateContainerCmdModifier(cmd -> cmd.getHostConfig()
.withCpuCount(2L));
@Override
public void initialize() throws Exception {
super.initialize();
testEnv.getConfig().disableObjectReuse();
testEnv.setStreamTimeCharacteristic(TimeCharacteristic.EventTime);
testEnv.setRestartStrategy(RestartStrategies.fixedDelayRestart(1, Time.of(1, TimeUnit.SECONDS)));
}
@Test
public void test() throws Throwable {
ArrayList<Message> messages = new ArrayList<>(20);
for (long i = 0; i < 20; i++) {
messages.add(new Message("cassandra-" + i));
}
Cluster cluster = cassandra.getCluster();
try (Session session = cluster.connect()) {
CassandraPojoSinkExample cassandraPojoSinkExample= new CassandraPojoSinkExample();
cassandraPojoSinkExample.doIt(cassandra.getHost(), testEnv.fromCollection(messages));
MappingManager manager= new MappingManager(session);
Mapper<Message> mapper=manager.mapper(Message.class);
String word ="cassandra-1";
Message message= mapper.get(word);
System.out.println(message);
}
}
Flink pipeline looks like (its only sink in doIt method):
public class CassandraPojoSinkExample {
private static final ArrayList<Message> messages = new ArrayList<>(20);
static {
for (long i = 0; i < 20; i++) {
messages.add(new Message("cassandra-" + i));
}
}
public static void main(String[] args) throws Exception {
// the main method is not used in tests
StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
DataStreamSource<Message> source = env.fromCollection(messages);
CassandraPojoSinkExample cassandraPojoSinkExample=new CassandraPojoSinkExample();
cassandraPojoSinkExample.doIt("127.0.0.1", source);
}
public void doIt(String address, DataStreamSource<Message> source) throws Exception {
CassandraSink.addSink(source)
.setClusterBuilder(new ClusterBuilder() {
@Override
protected Cluster buildCluster(Builder builder) {
return builder.addContactPoint(address).build();
}
})
.setMapperOptions(() -> new Mapper.Option[]{Mapper.Option.saveNullFields(true)})
.build();
}
When i run the test i got error:
16:41:57,675 ERROR org.apache.flink.streaming.runtime.tasks.StreamTask - Error during disposal of stream operator.
java.lang.NullPointerException
at org.apache.flink.streaming.connectors.cassandra.CassandraSinkBase.checkAsyncErrors(CassandraSinkBase.java:162)
at org.apache.flink.streaming.connectors.cassandra.CassandraSinkBase.close(CassandraSinkBase.java:96)
at org.apache.flink.api.common.functions.util.FunctionUtils.closeFunction(FunctionUtils.java:43)
at org.apache.flink.streaming.api.operators.AbstractUdfStreamOperator.dispose(AbstractUdfStreamOperator.java:117)
at org.apache.flink.streaming.runtime.tasks.StreamTask.disposeAllOperators(StreamTask.java:651)
at org.apache.flink.streaming.runtime.tasks.StreamTask.cleanUpInvoke(StreamTask.java:562)
at org.apache.flink.streaming.runtime.tasks.StreamTask.invoke(StreamTask.java:480)
at org.apache.flink.runtime.taskmanager.Task.doRun(Task.java:708)
at org.apache.flink.runtime.taskmanager.Task.run(Task.java:533)
at java.lang.Thread.run(Thread.java:748)
16:41:57,683 INFO org.apache.flink.runtime.taskmanager.Task - Source: Collection Source -> Sink: Cassandra Sink (1/1) (721a02e3c1345d640bf03b67eff0aba7) switched from RUNNING to FAILED.
com.datastax.driver.core.exceptions.NoHostAvailableException: All host(s) tried for query failed (tried: localhost/127.0.0.1:9042 (com.datastax.driver.core.exceptions.TransportException: [localhost/127.0.0.1] Cannot connect))
at com.datastax.driver.core.ControlConnection.reconnectInternal(ControlConnection.java:231)
at com.datastax.driver.core.ControlConnection.connect(ControlConnection.java:77)
at com.datastax.driver.core.Cluster$Manager.init(Cluster.java:1414)
at com.datastax.driver.core.Cluster.init(Cluster.java:162)
at com.datastax.driver.core.Cluster.connectAsync(Cluster.java:333)
at com.datastax.driver.core.Cluster.connect(Cluster.java:283)
at org.apache.flink.streaming.connectors.cassandra.CassandraPojoSink.createSession(CassandraPojoSink.java:123)
at org.apache.flink.streaming.connectors.cassandra.CassandraSinkBase.open(CassandraSinkBase.java:87)
at org.apache.flink.streaming.connectors.cassandra.CassandraPojoSink.open(CassandraPojoSink.java:106)
at org.apache.flink.api.common.functions.util.FunctionUtils.openFunction(FunctionUtils.java:36)
at org.apache.flink.streaming.api.operators.AbstractUdfStreamOperator.open(AbstractUdfStreamOperator.java:102)
at org.apache.flink.streaming.api.operators.StreamSink.open(StreamSink.java:48)
at org.apache.flink.streaming.runtime.tasks.StreamTask.initializeStateAndOpen(StreamTask.java:990)
at org.apache.flink.streaming.runtime.tasks.StreamTask.lambda$beforeInvoke$0(StreamTask.java:453)
at org.apache.flink.streaming.runtime.tasks.StreamTaskActionExecutor$SynchronizedStreamTaskActionExecutor.runThrowing(StreamTaskActionExecutor.java:94)
at org.apache.flink.streaming.runtime.tasks.StreamTask.beforeInvoke(StreamTask.java:448)
at org.apache.flink.streaming.runtime.tasks.StreamTask.invoke(StreamTask.java:460)
at org.apache.flink.runtime.taskmanager.Task.doRun(Task.java:708)
at org.apache.flink.runtime.taskmanager.Task.run(Task.java:533)
at java.lang.Thread.run(Thread.java:748)
What am I doing wrong here?
From the stacktrace above, com.datastax.driver.core.exceptions.NoHostAvailableException: All host(s) tried for query failed (tried: localhost/127.0.0.1:9042 it seems that the cassandra hosts are not available.
I would say you need to expose the ports to outside :
@Rule
public CassandraContainer cassandra = new CassandraContainer<>().withInitScript("testInit3.cql")
.withCreateContainerCmdModifier(cmd -> cmd.getHostConfig()
.withCpuCount(2L))
.withExposedPorts(9042);
Also, I would ensure manually via telnet to the corresponding host/port to make sure that service started.