| project | string | no | no | GCP project where the subscription exists. |
| credentials_json | string | no | no | JSON credentials for authenticating with GCP. |
| subscription | string | no | no | The ID of the subscription to consume messages from. |
| endpoint | string | yes | no | Allows you to specify a custom endpoint for the GCP API. For a list of valid values, see this document. The value defaults to ``. |
| sync | bool | yes | no | Whether to consume messages synchronously. If set to true, messages will be consumed one at a time and the next message will not be consumed until the current message has been acknowledged. If set to false, messages will be consumed in parallel and the next message will be consumed immediately after the current message has been acknowledged. This can improve throughput but may result in out-of-order message delivery. The value defaults to false. |
| max_outstanding_messages | int | yes | no | The maximum number of unacknowledged messages to allow before pausing consumption. If set to 0, consumption will never pause. This can be used to control the rate of consumption and prevent out-of-memory errors in the case of slow message processing. The value defaults to 1000. |
| max_outstanding_bytes | int | yes | no | The maximum number of unacknowledged bytes to allow before pausing consumption. If set to 0, consumption will never pause. This can be used to control the rate of consumption and prevent out-of-memory errors in the case of slow message processing. The value defaults to 1e+08. |
