Pub/Sub

The Cloud Pub/Sub connector lets you perform insert, delete, update, and read operations on Google Cloud Pub/Sub data.

Before you begin

Before using the Pub/Sub connector, do the following tasks:

  • In your Google Cloud project:
    • Ensure that network connectivity is set up. For information about network patterns, seeNetwork connectivity.
    • Grant theroles/connectors.admin IAM role to the user configuring the connector.
    • Grant the following IAM roles to the service account that you want to use for the connector:
      • roles/pubsub.publisher

      A service account is a special type of Google account intended to represent a non-human user that needs to authenticate and be authorized to access data in Google APIs. If you don't have a service account, you must create a service account. The connector and the service account must belong to the same project. For more information, seeCreating a service account.

    • Enable the following services:
      • secretmanager.googleapis.com (Secret Manager API)
      • connectors.googleapis.com (Connectors API)

      To understand how to enable services, seeEnabling services.

    If these services or permissions have not been enabled for your project previously, you are prompted to enable them when configuring the connector.

Configure the connector

A connection is specific to a data source. Itmeans that if you have many data sources, you must create a separate connectionfor each data source. To create a connection, do the following:

  1. In theCloud console, go to theIntegration Connectors > Connections page and then select or create a Google Cloud project.

    Go to the Connections page

  2. Click+ CREATE NEW to open theCreate Connection page.
  3. In theLocation section, choose the location for the connection.
    1. Region: Select a location from the drop-down list.

      For the list of all the supported regions, seeLocations.

    2. ClickNEXT.
  4. In theConnection Details section, complete the following:
    1. Connector: SelectPub/Sub from the drop down list of available Connectors.
    2. Connector version: Select the Connector version from the drop down list of available versions.
    3. In theConnection Name field, enter a name for the Connection instance.

      Connection names must meet the following criteria:

      • Connection names can use letters, numbers, or hyphens.
      • Letters must be lower-case.
      • Connection names must begin with a letter and end with a letter or number.
      • Connection names cannot exceed 49 characters.
    4. Optionally, enter aDescription for the connection instance.
    5. Optionally, enableCloud logging, and then select a log level. By default, the log level is set toError.
    6. Service Account: Select a service account that has therequired roles.
    7. Optionally, configure theConnection node settings:

      • Minimum number of nodes: Enter the minimum number of connection nodes.
      • Maximum number of nodes: Enter the maximum number of connection nodes.

      A node is a unit (or replica) of a connection that processes transactions. More nodes are required to process more transactions for a connection and conversely, fewer nodes are required to process fewer transactions. To understand how the nodes affect your connector pricing, see Pricing for connection nodes. If you don't enter any values, by default the minimum nodes are set to 2 (for better availability) and the maximum nodes are set to 50.

    8. Note: You can customize the connection node values only if you are a Pay-as-you-go customer.
    9. Project ID: Google Cloud project ID where the Pub/Sub instance resides.
    10. Topic ID: Optionally, enter the name of the Pub/Sub topic where the message should be published.

      If you don't specify a topic name here, you can specify the topic at runtime by configuring thetopic parameter in thePublishMessage action.

    11. Optionally, click+ ADD LABEL to add a label to the Connection in the form of a key/value pair.
    12. ClickNEXT.
  5. In theAuthentication section, enter the authentication details.
    1. The Pub/Sub connection doesn't require any authentication.
    2. ClickNEXT.
  6. Review: Review your connection and authentication details.
  7. ClickCreate.

Entities, operations, and actions

All the Integration Connectors provide a layer of abstraction for the objects ofthe connected application. You can access an application's objects only through this abstraction. The abstraction is exposed to you as entities, operations, and actions.

Note: You can view the entities, operations, and actions of a connector in theConnectors task.
  • Entity:An entity can be thought of as an object, or a collection of properties, in theconnected application or service. The definition of an entity differs from a connector to a connector. For example, in a database connector, tables are the entities, in a file server connector, folders are the entities, and in a messaging system connector, queues are the entities.

    However, it is possible that a connector doesn't support or have any entities, in which case theEntities list will be empty.

  • Operation:An operation is the activity that you can perform on an entity. You can performany of the following operations on an entity:

    Selecting an entity from the available list, generates a list ofoperations available for the entity. For a detailed description of the operations, see the Connectors task'sentity operations. However, if a connector doesn't support any of the entity operations, such unsupported operations aren't listed in theOperations list.

  • Action:An action is a first class function that is made available to the integrationthrough the connector interface. An action lets you make changes to an entity or entities, and vary from connector to connector. Normally, an action will have some input parameters, and an output parameter. However, it is possible that a connector doesn't support any action, in which case theActions list will be empty.
Note:All entities and actions will have a schema associated with them. For example, an action schema will have the parameter details such as; the parameternames, and its corresponding data type. The schema (metadata) for entities and actions is fetched by the connection atruntime from your backend. If there are any updates to the schema, such updates won't be automatically reflected in your existing connections; you must manually refresh the schema. To refreshthe schema for a connection, open theConnection details page of the connection, and then clickRefresh connection schema.

System limitations

The Pub/Sub connector can process a maximum of 27 transactions per second, pernode, andthrottles any transactions beyond this limit. By default, Integration Connectors allocates 2 nodes (for better availability) for a connection.

For information on the limits applicable to Integration Connectors, seeLimits.

Note: The number ofIntegration Connectors nodes will autoscale dynamically based on your usage. However, if you want to reserve capacity for large volumes without waiting for autoscaling, you can adjust the minimum node value for a connection. More nodes are required to process more transactions for a connection. Conversely, fewer nodes are required if a connection processes fewer transactions. To configure the node values, do the following:
  • If you are a pay-as-you-go customer, configure the minimum and maximum node value in the edit connection page.
  • If you are a subscription based customer,contact support.

The maximum transactions that a node can handle depends on various factors. So, before adjusting the minimum nodes for better throughput, it is recommended you check if your backend systems are set up optimally to handle the required traffic.

Actions

This section describes the actions supported by the Pub/Sub connector.

PublishMessage action

This action publishes a message to a Pub/Sub topic. The following table describes the input parameters of thePublishMessage action.

Parameter nameRequiredData typeDescription
topicNoStringName of the topic to which you want to publish the message.
messageYesStringThe message you want to publish. The message should be a stringified JSON and the maximum message size supported is 10 MB.
attributesNoStringCustom metadata (in the form of stringified JSON) as key-value pairs.
Note: The results of all the entity operations and actions will be available as a JSON response in theConnectors task'sconnectorOutputPayload response parameter after you run your integration.

Schema validation for messages

When you create a topic in Pub/Sub, you can choose to assign the topic a new or an existing schema. For more information, seecreate and manage schemas in Pub/Sub. If you have assigned a schema to a topic, your published messages are automatically validated against the schema and if a message doesn't confirm to the schema, the message isn't published.

Examples

This examples in this section describe the following operations:

  • Publish a message to a topic

The following table lists the sample scenarios and the corresponding configuration in the Connectors task:

TaskConfiguration
Publish a message to a topic
  1. In theConfigure connector task dialog, clickActions.
  2. Select thePublishMessage action, and then clickDone.
  3. In theTask Input section of theConnectors task, clickconnectorInputPayload and then enter a value similar to the following in theDefault Value field:
    {"message":"This is a test message.","topic":"mytopic","attributes":"{\"key1\":\"value1\"}"}
  4. ClickSave.

This example publishes the specifiedmessage to themytopic topic.

Running this example, returns a response smiliar to the following in the Connector task'sconnectorOutputPayload output variable:

{"messageIds":["7865292560686229"]}

Create connections using Terraform

You can use theTerraformresource to create a new connection.

To learn how to apply or remove a Terraform configuration, seeBasic Terraform commands.

To view a sample terraform template for connection creation, seesample template.

When creating this connection by using Terraform, you must set the following variables in your Terraform configuration file:

Parameter nameData typeRequiredDescription
project_idSTRINGTrueGoogle Cloud project ID where the Pub/Sub instance resides.
topic_idSTRINGFalseName of the Pub/Sub topic where the message should be published.

Use the Pub/Sub connection in an integration

After you create the connection, it becomes available in bothApigee Integration and Application Integration. You can use the connectionin an integration through the Connectors task.

  • To understand how to create and use the Connectors task in Apigee Integration, seeConnectors task.
  • To understand how to create and use the Connectors task in Application Integration, seeConnectors task.

Get help from the Google Cloud community

You can post your questions and discuss this connector in the Google Cloudcommunity atCloud Forums.

What's next

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Last updated 2026-02-18 UTC.