Updated on 2025-02-27 GMT+08:00

Creating a Topic

Scenarios

A topic serves as a message sending channel, where publishers and subscribers can interact with each other.

You can create your own topic.

Creating a Topic

  1. Log in to the management console.
  2. In the upper left corner, select a region and project.
  3. In the service list, select Simple Message Notification.

    The SMN console is displayed.

  4. In the navigation pane on the left, choose Topic Management > Topics.

    The Topics page is displayed.

  5. Click Create Topic.

    The Create Topic dialog box is displayed.

    Figure 1 Creating a topic
  6. Enter a topic name and display name (topic description).
    Table 1 Parameters required for creating a topic

    Parameter

    Description

    Topic Name

    Specifies the topic name, which

    • Contains only letters, digits, hyphens (-), and underscores (_) and must start with a letter or a digit.
    • Must contain 1 to 255 characters.
    • Must be unique and cannot be modified once the topic is created.

    Display Name

    Specifies the message sender name, which can contain up to 192 bytes.

    NOTE:

    After you specify a display name in Display name<username@example.com> format, the name you specify will be displayed as the email sender. Otherwise, the sender will be username@example.com.

    Enterprise Project

    Centrally manages cloud resources and members by project.

    CTS Log

    Specifies whether to enable CTS log.

    Log Group

    Select a log group.

    A log group is a group of log streams which share the same log retention settings. For details, see Managing Log Groups.

    Log Stream

    Select a log stream in the specified log group.

    A log stream is the basic unit for reading and writing logs. Sorting logs into different log streams makes it easier to find specific logs when you need them. For details, see Managing Log Streams.

    Tag

    Tags identify cloud resources so that they can be categorized easily and searched quickly.

    • For each resource, each tag key must be unique, and each tag key can have only one tag value.
    • A tag key can contain a maximum of 36 characters, including digits, letters, underscores (_), and hyphens (-).
    • A tag value can contain a maximum of 43 characters, including digits, letters, underscores (_), periods (.), and hyphens (-).
    • You can add up to 20 tags to a topic.
  7. Click OK.

    The topic you created is displayed in the topic list.

    After you create a topic, the system generates a uniform resource name (URN) for the topic, which uniquely identifies the topic and cannot be changed.

  8. Click a topic name to view the topic details and the total number of topic subscriptions.

Follow-up Operations

After you create a topic, add subscriptions. After the subscriptions have been confirmed, alarm notifications will be sent to the subscription endpoints via SMN.