Skip to main content

Managing persistent topics

Persistent helps to access topic which is a logical endpoint for publishing and consuming messages. Producers publish messages to the topic and consumers subscribe to the topic, to consume messages published to the topic.

In all of the instructions and commands below, the topic name structure is:


persistent://tenant/namespace/topic

Persistent topics resources​

List of topics​

It provides a list of persistent topics exist under a given namespace.

pulsar-admin​

List of topics can be fetched using list command.


$ pulsar-admin topics list \
my-tenant/my-namespace

REST API​

GET /admin/v2/:schema/:tenant/:namespace

Java​


String namespace = "my-tenant/my-namespace";
admin.persistentTopics().getList(namespace);

Grant permission​

It grants permissions on a client role to perform specific actions on a given topic.

pulsar-admin​

Permission can be granted using grant-permission command.


$ pulsar-admin topics grant-permission \
--actions produce,consume --role application1 \
persistent://test-tenant/ns1/tp1 \

REST API​

POST /admin/v2/:schema/:tenant/:namespace/:topic/permissions/:role

Java​


String topic = "persistent://my-tenant/my-namespace/my-topic";
String role = "test-role";
Set<AuthAction> actions = Sets.newHashSet(AuthAction.produce, AuthAction.consume);
admin.persistentTopics().grantPermission(topic, role, actions);

Get permission​

Permission can be fetched using permissions command.

pulsar-admin​


$ pulsar-admin topics permissions \
persistent://test-tenant/ns1/tp1 \

{
"application1": [
"consume",
"produce"
]
}

REST API​

GET /admin/v2/:schema/:tenant/:namespace/:topic/permissions

Java​


String topic = "persistent://my-tenant/my-namespace/my-topic";
admin.persistentTopics().getPermissions(topic);

Revoke permission​

It revokes a permission which was granted on a client role.

pulsar-admin​

Permission can be revoked using revoke-permission command.


$ pulsar-admin topics revoke-permission \
--role application1 \
persistent://test-tenant/ns1/tp1 \

{
"application1": [
"consume",
"produce"
]
}

REST API​

DELETE /admin/v2/:schema/:tenant/:namespace/:topic/permissions/:role

Java​


String topic = "persistent://my-tenant/my-namespace/my-topic";
String role = "test-role";
admin.persistentTopics().revokePermissions(topic, role);

Delete topic​

It deletes a topic. The topic cannot be deleted if there's any active subscription or producers connected to it.

pulsar-admin​

Topic can be deleted using delete command.


$ pulsar-admin topics delete \
persistent://test-tenant/ns1/tp1 \

REST API​

DELETE /admin/v2/:schema/:tenant/:namespace/:topic

Java​


String topic = "persistent://my-tenant/my-namespace/my-topic";
admin.persistentTopics().delete(topic);

Unload topic​

It unloads a topic.

pulsar-admin​

Topic can be unloaded using unload command.


$ pulsar-admin topics unload \
persistent://test-tenant/ns1/tp1 \

REST API​

PUT /admin/v2/:schema/:tenant/:namespace/:topic/unload

Java​


String topic = "persistent://my-tenant/my-namespace/my-topic";
admin.persistentTopics().unload(topic);

Get stats​

It shows current statistics of a given non-partitioned topic.

  • msgRateIn: The sum of all local and replication publishers' publish rates in messages per second

  • msgThroughputIn: Same as above, but in bytes per second instead of messages per second

  • msgRateOut: The sum of all local and replication consumers' dispatch rates in messages per second

  • msgThroughputOut: Same as above, but in bytes per second instead of messages per second

  • averageMsgSize: The average size in bytes of messages published within the last interval

  • storageSize: The sum of the ledgers' storage size for this topic. Space used to store the messages for the topic

  • publishers: The list of all local publishers into the topic. There can be zero or thousands

    • msgRateIn: Total rate of messages published by this publisher in messages per second

    • msgThroughputIn: Total throughput of the messages published by this publisher in bytes per second

    • averageMsgSize: Average message size in bytes from this publisher within the last interval

    • producerId: Internal identifier for this producer on this topic

    • producerName: Internal identifier for this producer, generated by the client library

    • address: IP address and source port for the connection of this producer

    • connectedSince: Timestamp this producer was created or last reconnected

  • subscriptions: The list of all local subscriptions to the topic

    • my-subscription: The name of this subscription (client defined)

      • msgRateOut: Total rate of messages delivered on this subscription (msg/s)

      • msgThroughputOut: Total throughput delivered on this subscription (bytes/s)

      • msgBacklog: Number of messages in the subscription backlog

      • type: This subscription type

      • msgRateExpired: The rate at which messages were discarded instead of dispatched from this subscription due to TTL

      • lastExpireTimestamp: The last message expire execution timestamp

      • lastConsumedFlowTimestamp: The last flow command received timestamp

      • lastConsumedTimestamp: The latest timestamp of all the consumed timestamp of the consumers

      • lastAckedTimestamp: The latest timestamp of all the acked timestamp of the consumers

      • consumers: The list of connected consumers for this subscription

        • msgRateOut: Total rate of messages delivered to the consumer (msg/s)

        • msgThroughputOut: Total throughput delivered to the consumer (bytes/s)

        • consumerName: Internal identifier for this consumer, generated by the client library

        • availablePermits: The number of messages this consumer has space for in the client library's listen queue. A value of 0 means the client library's queue is full and receive() isn't being called. A nonzero value means this consumer is ready to be dispatched messages.

        • unackedMessages: Number of unacknowledged messages for the consumer

        • blockedConsumerOnUnackedMsgs: Flag to verify if the consumer is blocked due to reaching threshold of unacked messages

        • lastConsumedTimestamp: The timestamp of the consumer last consume a message

        • lastAckedTimestamp: The timestamp of the consumer last ack a message

  • replication: This section gives the stats for cross-colo replication of this topic

    • msgRateIn: Total rate of messages received from the remote cluster (msg/s)

    • msgThroughputIn: Total throughput received from the remote cluster (bytes/s)

    • msgRateOut: Total rate of messages delivered to the replication-subscriber (msg/s)

    • msgThroughputOut: Total through delivered to the replication-subscriber (bytes/s)

    • msgRateExpired: Total rate of messages expired (msg/s)

    • replicationBacklog: Number of messages pending to be replicated to remote cluster

    • connected: Whether the outbound replicator is connected

    • replicationDelayInSeconds: How long the oldest message has been waiting to be sent through the connection, if connected is true

    • inboundConnection: The IP and port of the broker in the remote cluster's publisher connection to this broker

    • inboundConnectedSince: The TCP connection being used to publish messages to the remote cluster. If there are no local publishers connected, this connection is automatically closed after a minute.

    • outboundConnection: Address of outbound replication connection

    • outboundConnectedSince: Timestamp of establishing outbound connection


{
"msgRateIn": 4641.528542257553,
"msgThroughputIn": 44663039.74947473,
"msgRateOut": 0,
"msgThroughputOut": 0,
"averageMsgSize": 1232439.816728665,
"storageSize": 135532389160,
"publishers": [
{
"msgRateIn": 57.855383881403576,
"msgThroughputIn": 558994.7078932219,
"averageMsgSize": 613135,
"producerId": 0,
"producerName": null,
"address": null,
"connectedSince": null
}
],
"subscriptions": {
"my-topic_subscription": {
"msgRateOut": 0,
"msgThroughputOut": 0,
"msgBacklog": 116632,
"type": null,
"msgRateExpired": 36.98245516804671,
"consumers": []
}
},
"replication": {}
}

pulsar-admin​

Topic stats can be fetched using stats command.


$ pulsar-admin topics stats \
persistent://test-tenant/ns1/tp1 \

REST API​

GET /admin/v2/:schema/:tenant/:namespace/:topic/stats

Java​


String topic = "persistent://my-tenant/my-namespace/my-topic";
admin.persistentTopics().getStats(topic);

Get internal stats​

It shows detailed statistics of a topic.

  • entriesAddedCounter: Messages published since this broker loaded this topic

  • numberOfEntries: Total number of messages being tracked

  • totalSize: Total storage size in bytes of all messages

  • currentLedgerEntries: Count of messages written to the ledger currently open for writing

  • currentLedgerSize: Size in bytes of messages written to ledger currently open for writing

  • lastLedgerCreatedTimestamp: time when last ledger was created

  • lastLedgerCreationFailureTimestamp: time when last ledger was failed

  • waitingCursorsCount: How many cursors are "caught up" and waiting for a new message to be published

  • pendingAddEntriesCount: How many messages have (asynchronous) write requests we are waiting on completion

  • lastConfirmedEntry: The ledgerid:entryid of the last message successfully written. If the entryid is -1, then the ledger has been opened or is currently being opened but has no entries written yet.

  • state: The state of this ledger for writing. LedgerOpened means we have a ledger open for saving published messages.

  • ledgers: The ordered list of all ledgers for this topic holding its messages

    • ledgerId: Id of this ledger

    • entries: Total number of entries belong to this ledger

    • size: Size of messages written to this ledger (in bytes)

    • offloaded: Whether this ledger is offloaded

  • cursors: The list of all cursors on this topic. There will be one for every subscription you saw in the topic stats.

    • markDeletePosition: All of messages before the markDeletePosition are acknowledged by the subscriber.

    • readPosition: The latest position of subscriber for reading message

    • waitingReadOp: This is true when the subscription has read the latest message published to the topic and is waiting on new messages to be published.

    • pendingReadOps: The counter for how many outstanding read requests to the BookKeepers we have in progress

    • messagesConsumedCounter: Number of messages this cursor has acked since this broker loaded this topic

    • cursorLedger: The ledger being used to persistently store the current markDeletePosition

    • cursorLedgerLastEntry: The last entryid used to persistently store the current markDeletePosition

    • individuallyDeletedMessages: If Acks are being done out of order, shows the ranges of messages Acked between the markDeletePosition and the read-position

    • lastLedgerSwitchTimestamp: The last time the cursor ledger was rolled over

    • state: The state of the cursor ledger: Open means we have a cursor ledger for saving updates of the markDeletePosition.


{
"entriesAddedCounter": 20449518,
"numberOfEntries": 3233,
"totalSize": 331482,
"currentLedgerEntries": 3233,
"currentLedgerSize": 331482,
"lastLedgerCreatedTimestamp": "2016-06-29 03:00:23.825",
"lastLedgerCreationFailureTimestamp": null,
"waitingCursorsCount": 1,
"pendingAddEntriesCount": 0,
"lastConfirmedEntry": "324711539:3232",
"state": "LedgerOpened",
"ledgers": [
{
"ledgerId": 324711539,
"entries": 0,
"size": 0
}
],
"cursors": {
"my-subscription": {
"markDeletePosition": "324711539:3133",
"readPosition": "324711539:3233",
"waitingReadOp": true,
"pendingReadOps": 0,
"messagesConsumedCounter": 20449501,
"cursorLedger": 324702104,
"cursorLedgerLastEntry": 21,
"individuallyDeletedMessages": "[(324711539:3134β€₯324711539:3136], (324711539:3137β€₯324711539:3140], ]",
"lastLedgerSwitchTimestamp": "2016-06-29 01:30:19.313",
"state": "Open"
}
}
}

pulsar-admin​

Topic internal-stats can be fetched using stats-internal command.


$ pulsar-admin topics stats-internal \
persistent://test-tenant/ns1/tp1 \

REST API​

GET /admin/v2/:schema/:tenant/:namespace/:topic/internalStats

Java​


String topic = "persistent://my-tenant/my-namespace/my-topic";
admin.persistentTopics().getInternalStats(topic);

Peek messages​

It peeks N messages for a specific subscription of a given topic.

pulsar-admin​


$ pulsar-admin topics peek-messages \
--count 10 --subscription my-subscription \
persistent://test-tenant/ns1/tp1 \

Message ID: 315674752:0
Properties: { "X-Pulsar-publish-time" : "2015-07-13 17:40:28.451" }
msg-payload

REST API​

GET /admin/v2/:schema/:tenant/:namespace/:topic/subscription/:subName/position/:messagePosition

Java​


String topic = "persistent://my-tenant/my-namespace/my-topic";
String subName = "my-subscription";
int numMessages = 1;
admin.persistentTopics().peekMessages(topic, subName, numMessages);

Skip messages​

It skips N messages for a specific subscription of a given topic.

pulsar-admin​


$ pulsar-admin topics skip \
--count 10 --subscription my-subscription \
persistent://test-tenant/ns1/tp1 \

REST API​

POST /admin/v2/:schema/:tenant/:namespace/:topic/subscription/:subName/skip/:numMessages

Java​


String topic = "persistent://my-tenant/my-namespace/my-topic";
String subName = "my-subscription";
int numMessages = 1;
admin.persistentTopics().skipMessages(topic, subName, numMessages);

Skip all messages​

It skips all old messages for a specific subscription of a given topic.

pulsar-admin​


$ pulsar-admin topics skip-all \
--subscription my-subscription \
persistent://test-tenant/ns1/tp1 \

REST API​

POST /admin/v2/:schema/:tenant/:namespace/:topic/subscription/:subName/skip_all

More info

Java​


String topic = "persistent://my-tenant/my-namespace/my-topic";
String subName = "my-subscription";
admin.persistentTopics().skipAllMessages(topic, subName);

Reset cursor​

It resets a subscription’s cursor position back to the position which was recorded X minutes before. It essentially calculates time and position of cursor at X minutes before and resets it at that position.

pulsar-admin​


$ pulsar-admin topics reset-cursor \
--subscription my-subscription --time 10 \
persistent://test-tenant/ns1/tp1 \

REST API​

POST /admin/v2/:schema/:tenant/:namespace/:topic/subscription/:subName/resetcursor/:timestamp

Java​


String topic = "persistent://my-tenant/my-namespace/my-topic";
String subName = "my-subscription";
long timestamp = 2342343L;
admin.persistentTopics().skipAllMessages(topic, subName, timestamp);

Lookup of topic​

It locates broker url which is serving the given topic.

pulsar-admin​


$ pulsar-admin topics lookup \
persistent://test-tenant/ns1/tp1 \

"pulsar://broker1.org.com:4480"

REST API​

GET /lookup/v2/topic/persistent/:tenant:namespace/:topic

Java​


String topic = "persistent://my-tenant/my-namespace/my-topic";
admin.lookup().lookupDestination(topic);

Get bundle​

It gives range of the bundle which contains given topic

pulsar-admin​


$ pulsar-admin topics bundle-range \
persistent://test-tenant/ns1/tp1 \

"0x00000000_0xffffffff"

REST API​

GET /lookup/v2/topic/:topic_domain/:tenant/:namespace/:topic/bundle

Java​


String topic = "persistent://my-tenant/my-namespace/my-topic";
admin.lookup().getBundleRange(topic);

Get subscriptions​

It shows all subscription names for a given topic.

pulsar-admin​


$ pulsar-admin topics subscriptions \
persistent://test-tenant/ns1/tp1 \

my-subscription

REST API​

GET /admin/v2/:schema/:tenant/:namespace/:topic/subscriptions

Java​


String topic = "persistent://my-tenant/my-namespace/my-topic";
admin.persistentTopics().getSubscriptions(topic);

Unsubscribe​

It can also help to unsubscribe a subscription which is no more processing further messages.

pulsar-admin​


$ pulsar-admin topics unsubscribe \
--subscription my-subscription \
persistent://test-tenant/ns1/tp1 \

REST API​

DELETE /admin/v2/namespaces/:tenant/:namespace/:topic/subscription/:subscription

Java​


String topic = "persistent://my-tenant/my-namespace/my-topic";
String subscriptionName = "my-subscription";
admin.persistentTopics().deleteSubscription(topic, subscriptionName);

Last Message Id​

It gives the last committed message ID for a persistent topic, and it will be available in 2.3.0.


pulsar-admin topics last-message-id topic-name

REST API​

{% endpoint Get /admin/v2/:schema/:tenant/:namespace/:topic/lastMessageId %}

Java​


String topic = "persistent://my-tenant/my-namespace/my-topic";
admin.persistentTopics().getLastMessage(topic);