apache/pulsar · error · UnsupportedOperationException

The only supported ActionType is DELETE

Error message

The only supported ActionType is DELETE

What it means

validateActionType guards writes to the topic-policies system topic: the PulsarEvent's ActionType is missing or is not DELETE, the only action this writer supports, so the malformed policy event is rejected.

Source

Thrown at pulsar-broker/src/main/java/org/apache/pulsar/broker/systopic/TopicPoliciesSystemTopicClient.java:157

                systemTopicClient.getWriters().remove(TopicPolicyWriter.this);
            });
        }

        @Override
        public SystemTopicClient<PulsarEvent> getSystemTopicClient() {
            return systemTopicClient;
        }
    }

    private static void setReplicateCluster(PulsarEvent event, TypedMessageBuilder<PulsarEvent> builder) {
        if (event.getReplicateTo() != null) {
            builder.replicationClusters(new ArrayList<>(event.getReplicateTo()));
        }
    }

    private static void validateActionType(PulsarEvent event) {
        if (event == null || !ActionType.DELETE.equals(event.getActionType())) {
            throw new UnsupportedOperationException("The only supported ActionType is DELETE");
        }
    }

    private static class TopicPolicyReader implements Reader<PulsarEvent> {

        private final org.apache.pulsar.client.api.Reader<PulsarEvent> reader;
        private final TopicPoliciesSystemTopicClient systemTopic;

        private TopicPolicyReader(org.apache.pulsar.client.api.Reader<PulsarEvent> reader,
                                  TopicPoliciesSystemTopicClient systemTopic) {
            this.reader = reader;
            this.systemTopic = systemTopic;
        }

        @Override
        public Message<PulsarEvent> readNext() throws PulsarClientException {
            return reader.readNext();
        }

View on GitHub (pinned to 820761864e)

Solutions

1. Emit only DELETE action events on this code path

When it happens

Trigger: Thrown at pulsar-broker/src/main/java/org/apache/pulsar/broker/systopic/TopicPoliciesSystemTopicClient.java:157 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of apache/pulsar@820761864e (2026-09-06). Data as JSON: /api/errors/c39d69e14c2f6f14. Report an issue: GitHub.