[
https://issues.apache.org/jira/browse/KAFKA-12704?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Kalpesh Patel reassigned KAFKA-12704:
-------------------------------------
Assignee: Kalpesh Patel
> Concurrent calls to AbstractHerder::getConnector can potentially create two
> connector instances
> -----------------------------------------------------------------------------------------------
>
> Key: KAFKA-12704
> URL: https://issues.apache.org/jira/browse/KAFKA-12704
> Project: Kafka
> Issue Type: Bug
> Components: KafkaConnect
> Reporter: Kalpesh Patel
> Assignee: Kalpesh Patel
> Priority: Minor
>
> Requests to the {{PUT /connector-plugins/\{connectorType}/config/validate}}
> endpoint are [delegated to the
> herder|https://github.com/apache/kafka/blob/16ee326755e3f13914a0ed446c34c84e65fc0bc4/connect/runtime/src/main/java/org/apache/kafka/connect/runtime/rest/resources/ConnectorPluginsResource.java#L81],
> which [caches connector
> instances|https://github.com/apache/kafka/blob/16ee326755e3f13914a0ed446c34c84e65fc0bc4/connect/runtime/src/main/java/org/apache/kafka/connect/runtime/AbstractHerder.java#L536-L544]
> that are used [during config
> validation|https://github.com/apache/kafka/blob/16ee326755e3f13914a0ed446c34c84e65fc0bc4/connect/runtime/src/main/java/org/apache/kafka/connect/runtime/AbstractHerder.java#L310].
> This has the effect that, should concurrent requests to that endpoint occur
> for the same connector type, the same connector instance may be responsible
> for [validating those
> configurations|https://github.com/apache/kafka/blob/16ee326755e3f13914a0ed446c34c84e65fc0bc4/connect/runtime/src/main/java/org/apache/kafka/connect/runtime/AbstractHerder.java#L334]
> concurrently _(may_ instead of _will_ because there is also a race condition
> in the {{AbstractHerder::getConnector}} method that potentially fails to
> detect that an instance of the connector has already been created and, as a
> result, creates a second instance).
> This is slightly problematic because the
> [Connector::validate|https://github.com/apache/kafka/blob/16ee326755e3f13914a0ed446c34c84e65fc0bc4/connect/api/src/main/java/org/apache/kafka/connect/connector/Connector.java#L122-L127]
> method is not marked as thread-safe. However, because a lot of connectors
> out there tend to use the default implementation for that method, it's
> probably not super urgent that we patch this immediately.
> A couple of options are:
> # Update the docs for that method to specify that it must be thread-safe
> # Rewrite the connector validation logic in the framework to avoid
> concurrently invoking {{Connector::validate}} on the same instance.
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
