Hi Ruibin, "metrics.reporter.prom.class" is deprecated in 1.16, maybe " metrics.reporter.prom.factory.class"[1] can solve your problem. After reading the related code[2], I think the root cause is that " metrics.reporter.prom.class" would load the code via flink's classpath instead of MetricReporterFactory, due to "Plugins cannot access classes from other plugins or from Flink that have not been specifically whitelisted"[3], so ClassNotFoundException is thrown.
[1] https://nightlies.apache.org/flink/flink-docs-release-1.16/docs/deployment/metric_reporters/#prometheus [2] https://github.com/apache/flink/blob/release-1.16/flink-runtime/src/main/java/org/apache/flink/runtime/metrics/ReporterSetup.java#L457 [3] https://nightlies.apache.org/flink/flink-docs-stable/docs/deployment/filesystems/plugins/ Matthias Pohl via user <user@flink.apache.org> 于2023年1月2日周一 20:27写道： > Hi Ruibin, > could you switch to using the currently supported way for instantiating > reporters using the factory configuration parameter [1][2]? > > Based on the ClassNotFoundException, your suspicion might be right that > the plugin didn't make it onto the classpath. Could you share the > startup logs of the JM and TMs. That might help getting a bit more context > on what's going on. Your approach on integrating the reporter through the > plugin system [3] sounds about right as far as I can see. > > Matthias > > [1] > https://nightlies.apache.org/flink/flink-docs-master/docs/deployment/metric_reporters/#factory-class > [2] > https://nightlies.apache.org/flink/flink-docs-master/docs/deployment/metric_reporters/#prometheus > [3] > https://nightlies.apache.org/flink/flink-docs-master/docs/deployment/filesystems/plugins/ > > On Fri, Dec 30, 2022 at 11:42 AM Ruibin Xing <xingro...@gmail.com> wrote: > >> Hi community, >> >> I am having difficulty understanding the Flink plugin system. I am >> attempting to enable the Prometheus exporter with the official Flink image >> 1.16.0, but I am experiencing issues with library dependencies. According >> to the plugin documentation ( >> https://nightlies.apache.org/flink/flink-docs-stable/docs/deployment/filesystems/plugins/), >> as long as the library is located in the /opt/flink/plugins/<plugin-name> >> directory, Flink should automatically load it, similar to how it loads >> libraries in the /opt/flink/lib directory. However, Flink does not seem to >> detect the plugin. >> >> Here is the directory structure for /opt/flink: >> > tree /opt/flink >> . >> .... >> ├── plugins >> │ ├── metrics-prometheus >> │ │ └── flink-metrics-prometheus-1.16.0.jar >> ... >> >> And here is the related Flink configuration: >> > metrics.reporter.prom.class: >> org.apache.flink.metrics.prometheus.PrometheusReporter >> >> The error logs in the task manager show the following: >> 2022-12-30 10:03:55,840 WARN >> org.apache.flink.runtime.metrics.ReporterSetup [] - The >> reporter configuration of 'prom' configures the reporter class, which is a >> deprecated approach to configure reporters. Please configure a factory >> class instead: 'metrics.reporter.prom.factory.class: <factoryClass>' to >> ensure that the configuration continues to work with future versions. >> 2022-12-30 10:03:55,841 ERROR >> org.apache.flink.runtime.metrics.ReporterSetup [] - Could not >> instantiate metrics reporter prom. Metrics might not be exposed/reported. >> java.lang.ClassNotFoundException: >> org.apache.flink.metrics.prometheus.PrometheusReporter >> at jdk.internal.loader.BuiltinClassLoader.loadClass(Unknown Source) ~[?:?] >> at jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(Unknown >> Source) ~[?:?] >> at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:?] >> at java.lang.Class.forName0(Native Method) ~[?:?] >> at java.lang.Class.forName(Unknown Source) ~[?:?] >> at >> org.apache.flink.runtime.metrics.ReporterSetup.loadViaReflection(ReporterSetup.java:456) >> ~[flink-dist-1.16.0.jar:1.16.0] >> at >> org.apache.flink.runtime.metrics.ReporterSetup.loadReporter(ReporterSetup.java:409) >> ~[flink-dist-1.16.0.jar:1.16.0] >> at >> org.apache.flink.runtime.metrics.ReporterSetup.setupReporters(ReporterSetup.java:328) >> ~[flink-dist-1.16.0.jar:1.16.0] >> at >> org.apache.flink.runtime.metrics.ReporterSetup.fromConfiguration(ReporterSetup.java:209) >> ~[flink-dist-1.16.0.jar:1.16.0] >> >> The Java commands for Flink process: >> flink 1 3.0 4.6 2168308 765936 ? Ssl 10:03 1:08 >> /opt/java/openjdk/bin/java -XX:+UseG1GC -Xmx697932173 -Xms697932173 >> -XX:MaxDirectMemorySize=300647712 -XX:MaxMetaspaceSize=268435456 >> -Dlog.file=/opt/flink/log/flink--kubernetes-taskmanager-0-checkpoint-ha-example-taskmanager-1-1.log >> -Dlog4j.configuration=file:/opt/flink/conf/log4j-console.properties >> -Dlog4j.configurationFile=file:/opt/flink/conf/log4j-console.properties >> -Dlogback.configurationFile=file:/opt/flink/conf/logback-console.xml >> -classpath >> /opt/flink/lib/flink-cep-1.16.0.jar:/opt/flink/lib/flink-connector-files-1.16.0.jar:/opt/flink/lib/flink-csv-1.16.0.jar:/opt/flink/lib/flink-json-1.16.0.jar:/opt/flink/lib/flink-scala_2.12-1.16.0.jar:/opt/flink/lib/flink-shaded-hadoop-2-uber-2.4.1-10.0.jar:/opt/flink/lib/flink-shaded-zookeeper-3.5.9.jar:/opt/flink/lib/flink-table-api-java-uber-1.16.0.jar:/opt/flink/lib/flink-table-planner-loader-1.16.0.jar:/opt/flink/lib/flink-table-runtime-1.16.0.jar:/opt/flink/lib/log4j-1.2-api-2.17.1.jar:/opt/flink/lib/log4j-api-2.17.1.jar:/opt/flink/lib/log4j-core-2.17.1.jar:/opt/flink/lib/log4j-slf4j-impl-2.17.1.jar:/opt/flink/lib/flink-dist-1.16.0.jar:::: >> org.apache.flink.kubernetes.taskmanager.KubernetesTaskExecutorRunner >> --configDir /opt/flink/conf -Djobmanager.rpc.address=172.17.0.7 >> -Dpipeline.classpaths= -Djobmanager.memory.off-heap.size=134217728b >> -Dweb.tmpdir=/tmp/flink-web-57b9e638-f313-4389-a75b-988509697edb >> -Djobmanager.rpc.port=6123 >> -D.pipeline.job-id=ffffffffa6f1c9fb0000000000000000 >> -Drest.address=172.17.0.7 -Djobmanager.memory.jvm-overhead.max=214748368b >> -Djobmanager.memory.jvm-overhead.min=214748368b >> -Dtaskmanager.resource-id=checkpoint-ha-example-taskmanager-1-1 >> -Dexecution.target=embedded >> -Dpipeline.jars=file:/opt/flink/examples/streaming/StateMachineExample.jar >> -Djobmanager.memory.jvm-metaspace.size=268435456b >> -Djobmanager.memory.heap.size=1530082096b -D >> taskmanager.memory.network.min=166429984b -D taskmanager.cpu.cores=1.0 -D >> taskmanager.memory.task.off-heap.size=0b -D >> taskmanager.memory.jvm-metaspace.size=268435456b -D external-resources=none >> -D taskmanager.memory.jvm-overhead.min=214748368b -D >> taskmanager.memory.framework.off-heap.size=134217728b -D >> taskmanager.memory.network.max=166429984b -D >> taskmanager.memory.framework.heap.size=134217728b -D >> taskmanager.memory.managed.size=665719939b -D >> taskmanager.memory.task.heap.size=563714445b -D >> taskmanager.numberOfTaskSlots=1 -D >> taskmanager.memory.jvm-overhead.max=214748368b >> >> It seems that I must be missing something. Could someone please help me >> clarify this issue? >> >> Thank you, >> >> Ruibin >> > -- Best, Yanfei
