TDMQ for Apache Pulsar

TDMQ for Apache Pulsar
Glossary
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TDMQ for Apache Pulsar

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TDMQ for Apache Pulsar

Glossary：

Last updated 2024-01-03 14:27:38

Scheduled Message
After a message is sent to the server, the business may want the consumer to receive it at a later time point rather
than immediately. This type of message is called "scheduled message".

Subscription TypeA subscription type (subscriptionType) is a type of topic subscription by a consumer. You can specify multiple
subscription types, such as exclusive, failover, and shared.

Subscription Name
A subscription name (subscriptionName) uniquely identifies a group of subscribers.

Partition Index
A partition index (partionindex) denotes the number of a partition in a topic.

Shared TypeThe shared type is a subscription type where a subscriber group can have multiple concurrent active consumer
connections, and a message consumed by one of the consumers will not be consumed again by other consumers.

Namespace
In TSF, a namespace is an abstract collection of resources and objects. It isolates resources in the same cluster, so
you can use the same account to create different environments.
A cluster can have multiple namespaces, but a resource in the cluster can belong to only one namespace. With
namespaces, you can divide a cluster into the development environment, test environment, etc. If there are active
network connections, services in the same namespace can discover and call each other.
In TCR, a namespace is a directory hierarchy in an instance like an organization in Docker Hub or a project in Harbor,which can be used to isolate image repositories of different projects, teams, or other organizations. A namespace falls
between an instance and a repository, and its access level attribute directly determines the public or private attributeof image repositories in it. Image repositories and Helm chart repositories can share a namespace.
In TDMQ, a namespace manages associated topics as a group. It is the basic unit of topic management. Each tenant
can have multiple namespaces which correspond to different Tencent Cloud environments.

Exclusive TypeThe exclusive type is a subscription type where a subscriber group can have only one active consumer.

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Batch ID
A batch ID (batchid) denotes the number of a message in a batch of messages.

Producer
A producer refers to a role that sends messages.

TDMQ
See TDMQ.

Entry
An entry is an element of a ledger, and a ledger is composed of a set of entries.

Consumer
A consumer refers to a role that receives messages.

Message ID
A message ID is the unique identifier of a message, which consists of four parts: ledgerid , entryid ,partionindex , and batchid .
Each message will receive a message ID assigned by the Tencent Cloud system, which can be returned to you
through the SendMessage API request.

Message Retention Period
The message retention period refers to the retention period of a message that has been acknowledged by the
consumer.

TDMQ
Tencent Distributed Message Queue (TDMQ) for Pulsar is a proprietary finance-grade distributed message
middleware developed based on Pulsar, a top open-source project of Apache. It features high cross-region
consistency, reliability, and concurrency. Currently, it is widely used in Tencent's most billing scenarios, including
primary payment process as well as real-time reconciliation, monitoring, and big data analysis.

Message Expiry Time
Message expiry time refers to the time to live (TTL) of an unacknowledged message.

Message TypeA message type is used to identify the type of a topic. Two topic types are supported: persistent and non-persistent. A
persistent topic will return an ack for successful delivery after the message is stored to the disk.

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TDMQ for Apache Pulsar

Delayed Message
After a message is sent to the server, the business may want the consumer to receive it after a period of time rather
than immediately. This type of message is called "delayed message".

Failover TypeThe failover type is a subscription type where subscribers can exist in a primary/secondary relationship. The primaryconsumer consumes messages under normal conditions, and consumption will be switched to the secondary
consumer when the primary consumer fails.

LedgerA ledger is an element in a topic, and a topic is composed of a set of ledgers.

Topic
In Oceanus, a topic is the smallest unit of stream connection to subscription and publishing. You can use a topic todenote a type of streaming data, just like a table in a database.
In IoT Hub, a topic refers to a message communication topic, acting as the communication intermediary of themessages in the Pub/Sub pattern. It is required when publishing and subscribing to messages, and thecommunication is made based on the specific topic of each device.
In TDMQ, CKafka, and CMQ, a topic refers to a collection of messages of a particular type. It is a logical concept used
to store messages. Topics must be unique in a namespace.
In CLS, a topic refers to the basic management unit provided by CLS. A log topic corresponds to an application orservice and is the smallest management unit in CLS, around which collection, indexing, and delivery are configured. A
logset can contain multiple log topics.
In BI, a topic is a way to batch modify the styles of the overall components in order to make the report design more
uniform. In BI systems, topics are often used for unified settings of chart components and page backgrounds.

TenantA tenant corresponds to an APPID in Tencent Cloud.

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