Version: 0.1.10

Debug Pulsar connectors

This document describes how to debug Pulsar connectors through Pod logs, connector log topics, and pulsar-admin commands.

Use Pod logs

Logs in Kubernetes give you insight into resources such as nodes, Pods, containers, deployments and replica sets. This insight allows you to observe the interactions between those resources and see the effects that one action has on another. Pod logs record events happening in a cluster, which can be very useful for debugging. Before debugging a Pod, you need to ensure the Pod is already scheduled and running.

The built-in way to check logs on your Kubernetes cluster is with kubectl CLI commands. You can use the kubectl logs pod POD_NAME -n NAMESPACE_NAME to check logs of the affected container. In addition, you can use kubectl logs pod POD_NAME -n NAMESPACE_NAME --previous to retrieve logs from a previous instantiation of a container.

In addition, you can use the following command to check the specific Pod.

  • kubectl get pod POD_NAME -n NAMESPACE_NAME: check Pod status.

  • kubectl describe pod POD_NAME -n NAMESPACE_NAME: check the current state of the Pod and recent events.

For the use of kubectl commands, see kubectl command reference.

Use log topics

In Pulsar connectors, you can generate log information defined in connectors to a specified log topic. You can configure consumers to consume messages from a specified log topic to check the log information.

  • This example shows how to specify the log topic through the YAML file.

    apiVersion: cloud.streamnative.io/v1alpha1
    kind: Source
    metadata:
    name: source-sample
    spec:
    className: org.apache.pulsar.io.debezium.mongodb.DebeziumMongoDbSource
    replicas: 1
    maxReplicas: 3
    output:
    producerConf:
    maxPendingMessages: 1000
    maxPendingMessagesAcrossPartitions: 50000
    useThreadLocalProducers: true
    topic: persistent://public/default/destination
    typeClassName: org.apache.pulsar.common.schema.KeyValue
    resources:
    limits:
    cpu: "0.2"
    memory: 1.1G
    requests:
    cpu: "0.1"
    memory: 1G
    # Other source configs
  • This example shows how to specify the log topic through the pulsar-admin CLI tool.

    Note

    To use the pulsar-admin CLI tool to monitor Pulsar functions and connectors, you should start Function Mesh Worker service in advance. For details, see work with pulsar-admin CLI tool.

    bin/pulsar-admin sinks create \
    --log-topic persistent://public/default/logging-sink-logs \
    # Other sink configs

Use pulsar-admin CLI tool

Note

To use the pulsar-admin CLI tool to monitor Pulsar functions and connectors, you should start Function Mesh Worker service in advance. For details, see work with pulsar-admin CLI tool.

To debug a Pulsar connector, you can perform the following operations.

For more information, see Pulsar source CLIs and Pulsar sink CLIs.

get

You can get the information of a Pulsar connector.

  • The pulsar-admin sources get command is used to get the information of a Pulsar source connector.

    pulsar-admin sources get options
  • The pulsar-admin sinks get command is used to get the information of a Pulsar sink connector.

    pulsar-admin sinks get options

status

You can get the current status of a Pulsar connector.

  • The pulsar-admin sources status command is used to check the current status of a Pulsar source connector.

    pulsar-admin sources status options
  • The pulsar-admin sinks status command is used to check the current status of a Pulsar sink connector.

    pulsar-admin sinks status options

topics stats

The pulsar-admin topics stats command is used to check the stats for the input or output topic of a connector, and the connected producer and consumer, including information about received messages and backlog, and available permits.

pulsar-admin topics stats options

For more information about the pulsar-admin topic stats command, see topic stats.