pgaref commented on code in PR #22468: URL: https://github.com/apache/flink/pull/22468#discussion_r1318966093
########## docs/content/docs/deployment/advanced/failure_enrichers.md: ########## @@ -0,0 +1,106 @@ +--- +title: "Failure Enrichers" +nav-title: failure-enrichers +nav-parent_id: advanced +nav-pos: 3 +--- +<!-- +Licensed to the Apache Software Foundation (ASF) under one +or more contributor license agreements. See the NOTICE file +distributed with this work for additional information +regarding copyright ownership. The ASF licenses this file +to you under the Apache License, Version 2.0 (the +"License"); you may not use this file except in compliance +with the License. You may obtain a copy of the License at + http://www.apache.org/licenses/LICENSE-2.0 +Unless required by applicable law or agreed to in writing, +software distributed under the License is distributed on an +"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +KIND, either express or implied. See the License for the +specific language governing permissions and limitations +under the License. +--> + +## Custom failure enrichers +Flink provides a pluggable interface for users to register their custom logic and enrich failures with extra metadata labels (string key-value pairs). +This enables users to implement their own failure enrichment plugins to categorize job failures, expose custom metrics, or make calls to external notification systems. + +FailureEnrichers are triggered every time an exception is reported at runtime by the JobManager. +Every FailureEnricher may asynchronously return labels associated with the failure that are then exposed via the JobManager's REST API (e.g., a 'type:System' label implying the failure is categorized as a system error). + + +### Implement a plugin for your custom enricher + +To implement a custom FailureEnricher plugin, you need to: + +- Add your own FailureEnricher by implementing the {{< gh_link file="/flink-core/src/main/java/org/apache/flink/core/failure/FailureEnricher.java" name="FailureEnricher" >}} interface. + +- Add your own FailureEnricherFactory by implementing the {{< gh_link file="/flink-core/src/main/java/org/apache/flink/core/failure/FailureEnricherFactory.java" name="FailureEnricherFactory" >}} interface. + +- Add a service entry. Create a file `META-INF/services/org.apache.flink.core.failure.FailureEnricherFactory` which contains the class name of your failure enricher factory class (see [Java Service Loader](https://docs.oracle.com/en/java/javase/17/docs/api/java.base/java/util/ServiceLoader.html) docs for more details). + + +Then, create a jar which includes your `FailureEnricher`, `FailureEnricherFactory`, `META-INF/services/` and all external dependencies. +Make a directory in `plugins/` of your Flink distribution with an arbitrary name, e.g. "failure-enrichment", and put the jar into this directory. +See [Flink Plugin]({% link deployment/filesystems/plugins.md %}) for more details. + +{{< hint warning >}} +Note that every FailureEnricher should have defined a set of {{< gh_link file="/flink-core/src/main/java/org/apache/flink/core/failure/FailureEnricher.java" name="output keys" >}} that may be associated with values. This set of keys has to be unique across enrichers otherwise values associated with them may be ignored. +{{< /hint >}} + +FailureEnricherFactory example: + +``` java +public class TestFailureEnricherFactory implements FailureEnricherFactory { + + @Override + public FailureEnricher createFailureEnricher(Configuration conf) { + return new CustomEnricher(); + } +} +``` + +FailureEnricher example: + +``` java +public class CustomEnricher implements FailureEnricher { + private final Set<String> outputKeys; + + public CustomEnricher() { + this.outputKeys = Collections.singleton("labelKey"); + } + + @Override + public Set<String> getOutputKeys() { + return outputKeys; + } + + @Override + public CompletableFuture<Map<String, String>> processFailure( + Throwable cause, Context context) { + return CompletableFuture.completedFuture(Collections.singletonMap("labelKey", "labelValue")); + } +} +``` + +### Configuration + +The JobManager loads FailureEnricher plugins at startup. To make sure your FailureEnrichers are loaded all class names should be defined as part of [jobmanager.failure-enrichers configuration]({{< ref "docs/deployment/config#jobmanager-failure-enrichers" >}}). + If this configuration is empty, NO enrichers will be started. Example: +``` + jobmanager.failure-enrichers = org.apache.flink.test.plugin.jar.failure.CustomEnricher Review Comment: Yes, this is the first version of the feature -- if many enrichers are loaded we could easily change that to what metrics reporters do but looked like an overkill for now -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
