apache/pulsar · error · RestException

maxProducersPerTopic must be 0 or more

Error message

maxProducersPerTopic must be 0 or more

What it means

Thrown by internalSetMaxProducersPerTopic when the provided value is negative. The max-producers-per-topic limit is a count and must be null (unset) or >= 0. The broker rejects the update with HTTP 412 PRECONDITION_FAILED before touching the policies.

Source

Thrown at pulsar-broker/src/main/java/org/apache/pulsar/broker/admin/impl/NamespacesBase.java:2456

                }
            });
    }

    protected void internalSetDeduplicationSnapshotInterval(Integer interval) {
        validateNamespacePolicyOperation(namespaceName, PolicyName.DEDUPLICATION_SNAPSHOT, PolicyOperation.WRITE);
        if (interval != null && interval < 0) {
            throw new RestException(Status.PRECONDITION_FAILED, "interval must be greater than or equal to 0");
        }
        internalSetPolicies("deduplicationSnapshotIntervalSeconds", interval);
    }

    protected void internalSetMaxProducersPerTopic(Integer maxProducersPerTopic) {
        validateNamespacePolicyOperation(namespaceName, PolicyName.MAX_PRODUCERS, PolicyOperation.WRITE);
        validatePoliciesReadOnlyAccess();

        try {
            if (maxProducersPerTopic != null && maxProducersPerTopic < 0) {
                throw new RestException(Status.PRECONDITION_FAILED,
                        "maxProducersPerTopic must be 0 or more");
            }
            updatePolicies(namespaceName, policies -> {
                policies.max_producers_per_topic = maxProducersPerTopic;
                return policies;
            });
            log.info()
                    .attr("namespace", namespaceName)
                    .attr("maxProducersPerTopic", maxProducersPerTopic)
                    .log("Successfully updated maxProducersPerTopic configuration");
        } catch (RestException pfe) {
            throw pfe;
        } catch (Exception e) {
            log.error()
                    .attr("namespace", namespaceName)
                    .exception(e)
                    .log("Failed to update maxProducersPerTopic configuration for namespace");
            throw new RestException(e);

View on GitHub (pinned to 820761864e)

Solutions

1. Pass 0 or a positive integer (0 means no producers allowed; null/omit means no limit)
2. Use null to unset the limit instead of -1
3. Add client-side validation (value == null || value >= 0) before the API call

Example fix

// before
admin.namespaces().setMaxProducersPerTopic("my-tenant/my-ns", -1); // 412
// after
admin.namespaces().setMaxProducersPerTopic("my-tenant/my-ns", null);  // unset / unlimited
admin.namespaces().setMaxProducersPerTopic("my-tenant/my-ns", 100);   // explicit limit

if (maxProducersPerTopic != null && maxProducersPerTopic < 0) {
    throw new IllegalArgumentException("maxProducersPerTopic must be >= 0 or null");
}

boolean isValidCount(Integer v) { return v == null || v >= 0; }

try {
    admin.namespaces().setMaxProducersPerTopic(ns, maxProducersPerTopic);
} catch (PulsarAdminException.PreconditionFailedException e) {
    log.error("Negative maxProducersPerTopic rejected: use null for unlimited");
    throw e;
}

When it happens

Trigger: POST /namespaces/{ns}/maxProducersPerTopic with a negative integer; passing -1 intending 'unlimited' when the correct sentinel is null or 0; variable interpolation bugs in config producing negative numbers.

Common situations: Using -1 as 'no limit' (Pulsar expects null/omit); copying limits from another system with different sentinel conventions; CLI tools that don't validate input.

Related errors

• Topic name is not valid
• Partitioned Topic Name should not contain '-partition-'
• Invalid value for message TTL
• interval must be greater than or equal to 0
• maxConsumersPerTopic must be 0 or more

AI-assisted analysis of apache/pulsar@820761864e (2026-09-06). Data as JSON: /api/errors/c7266ef635194dc3. Report an issue: GitHub.