Understand connectors

Workflows publishes connectors to make it easier to access other Google Cloud products within a workflow. For a detailed reference of available connectors, see the Connectors reference.

Connectors can be used to connect to other Google Cloud APIs within a workflow, and to integrate your workflows with those Google Cloud products. For example, you can use connectors to publish Pub/Sub messages, read or write data to a Firestore database, or retrieve authentication keys from Secret Manager. Learn how to use a connector.

Connectors simplify calling services because they handle the formatting of requests for you, providing methods and arguments so that you don't need to know the details of a Google Cloud API.

Connectors have built-in behavior for handling retries and long-running operations.


Connectors use built-in Identity and Access Management authentication to interact with other Google Cloud products. Note that a workflow using a connector still needs to have proper permissions assigned to its service account to properly authenticate to a given API. For example, to publish a message to Pub/Sub, the service account associated with your workflow needs to be granted the roles/pubsub.publisher role. To learn more about authenticating to other Google Cloud products, see Grant a workflow permission to access Google Cloud resources.


All connectors apply the following retry policy and error handling configurations:

  • Workflows uses an idempotent retry policy for GET requests.

  • Workflows uses a non-idempotent retry policy for all other HTTP methods.

  • By default, requests time out after 30 minutes. Note that for long-running operations, this applies to individual requests (for example, starting the operation or checking its status) within the long-running operation. The timeout for the entire operation can be configured using the connector_params field. See the Connectors reference.

Long-running operations

For calls performing a long-running operation, the following behaviors apply:

  • Workflows blocks the workflow execution until the operation completes successfully or fails.

  • By default, calls time out after 30 minutes. The timeout of the call can be changed using the connector_params field (to a maximum of one year). See the Connectors reference.

  • Connectors poll long-running operations periodically. By default, Workflows uses an exponential backoff of 1.25 when polling, starting with 1 second and slowing to 60 seconds between polls. Each polling attempt counts as a billable step. The polling parameters can be changed using the connector_params field. See the Connectors reference.

  • The preceding retry mechanism applies to a failed polling attempt.

  • Poll responses are checked and if the response payload is invalid, a ResponseTypeError error is returned.

  • When an error occurs during a long-running operation, Workflows raises an OperationError error. The error includes an additional attribute, error, which contains operation-specific details.

If a long-running operation fails, the connector call throws an exception with the following attributes:

  • message: Human-readable error message.
  • tags: A list of tags. For a long-running operation connector call, the list includes OperationError.
  • operation: The failed long-running operation object.

For a detailed list of supported long-running operation types, see the Connectors reference.

What's next