I am learning Flink for a new project. I am trying to understand the
development/debug environment to help me step through my code to better
learn Flink. I am using the Intellij community edition for my IDE and Flink
1.17.0.
I am using this simple Flink app to demonstrate my issue.
//===========================================================================
package streamwindowprocessor;
import org.apache.flink.configuration.Configuration;
import org.apache.flink.streaming.api.datastream.DataStream;
import
org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
public class SimpleFlink {
public static void main(String[] args) throws Exception {
Configuration conf = new Configuration();
final StreamExecutionEnvironment env =
StreamExecutionEnvironment.createLocalEnvironmentWithWebUI(conf);
// final StreamExecutionEnvironment env =
StreamExecutionEnvironment.getExecutionEnvironment();
DataStream<String> values = env.socketTextStream("localhost", 9999);
values.print();
env.execute("Alarm Stream Processor");
}
}
//===========================================================================
Before I run this from the IDE, I start up a socket listener on a terminal:
nc -lkp 9999
Then I open a web browser to localhost:8081 and get this output
{
- errors:
[
- "Not found: /"
]
}
If instead, I use ./start-cluster.sh to start a standalone cluster, rebuild
my jar using getExecutionEnvironment() and submit that same simple jar
using ./flink.sh run <path-to-jar>, then I can open the browser to
localhost:8081 and I do see my app running, as expected, and it processes
strings I send via the running netcat.
Someone in SO noted that you should add this dependency, which I did and it
made no difference.
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-runtime-web</artifactId>
<version>${flink.version}</version>
</dependency>
*Can anyone help me understand why the web UI does not work
in createLocalEnvironmentWithWebUI()?*
Thanks,
Mark
