# Google Cloud Pub/Sub ## Overview Google Cloud Pub/Sub provides messaging between applications reliably and asynchronously by sending publishing messages to a topic and subscribing to that topic to receive messages. ## \*\*API Information \*\* The Base URL used for the Google Cloud Pub/Sub connector is \*\*. \*\*More information can be found on their main [API documentation (v1.0)](https://cloud.google.com/pubsub/docs/apis) site. ## Authentication Within the builder, click on the Google Cloud Pub/Sub connector to display the connector properties panel. Select the 'Authentication' tab and click on the 'New authentication' button. In the Tray.io authentication pop-up modal, name the authentication in a way that will quickly identify it within a potentially large list. For example, whether it is a Sandbox or Production auth, etc. Consider who/ how many people will need access to this authentication when choosing where to create this authentication ('Personal' or 'Organisational'). The second page asks you for your 'Service Account' credentials. ![2nwGkmYqfLJkugCzSuwMrG](https://tray.ai/documentation/images/connectors/service/google-cloud-pub-sub/2nwGkmYqfLJkugCzSuwMrG_Screenshot%202022-06-21%20at%2017.35.33.png) To create a service account, head to the Google Cloud Pub/Sub [dashboard](https://console.cloud.google.com/projectselector/iam-admin/serviceaccounts/create?supportedpurview=project) and create a new service account for your selected project. Once created, please copy and paste the entire contents of your service account JSON file. For more information and advice on authenticating with a service account please refer to the Google Cloud documentation [here.](https://cloud.google.com/pubsub/docs/reference/libraries) Once you have added these fields to your Tray.io authentication pop-up window, click the 'Create authentication' button.  Your connector authentication setup should now be complete. ## Google Cloud Pub/Sub Trigger The Google Cloud Pub/Sub trigger allows you to receive notifications and trigger workflows when messages are published to a topic that has an associated subscription. ### Trigger Operations available: * Subscribe ### Subscribe Setup Select the Google Cloud Pub/Sub trigger. This can be done at the create new workflow stage or updated within the workflow builder itself. Highlight the Google Cloud Pub/Sub trigger. In the Google Cloud Pub/Sub trigger properties panel to the right of the builder, click on the Authenticate tab and the 'Add new authentication' button. The Google Cloud Pub/Sub trigger authentication follows the same steps as the connector. Follow the instructions above to authenticate your trigger. Select 'Subscribe' to create a subscription to a given topic in Google Cloud Pub/Sub. ![Google Cloud Pub/Sub Trigger](https://tray.ai/documentation/images/connectors/service/google-cloud-pub-sub/pBW7YXhBU3zkM5CvjjHlF_google-cloud-pubsub-trigger.png) As you can see, the 'Subscription', 'Project' and 'Topic' fields are required in order to subscribe to a topic. ## Available Operations The examples below show one or two of the available connector operations in use. Please see the [Full Operations Reference](#operationsFull) at the end of this page for details on all available operations for this connector. ## Notes on using Google Cloud Pub/Sub ### Publish/Subscribe In order to use the trigger in conjunction with the connector, please ensure that the topic subscribed in the trigger matches the topic published in the connector. ## Example Usage > **Info:** **TRAY POTENTIAL:** Tray is extremely flexible. By design there is no fixed way of working with it - you can pull whatever data you need from other services and work with it using our core and helper connectors. Below is an example of a way in which you could use the Google Cloud Pub/Sub connector to publish a message to a topic and trigger a workflow that has subscribed to the same topic to receive messages. The overall workflow would look like so: ![Google Cloud Pub/Sub Workflow complete](https://tray.ai/documentation/images/connectors/service/google-cloud-pub-sub/3gW0MATny6UGf70DRSMsAo_google-cloud-pub-sub.png) As you can see the 'Topic' is required and matches the Topic passed in the trigger. The message additionally must be provided and encoded as a base64 string. Once published, this will trigger the workflow we added the Google Cloud Pub/Sub trigger to with the data we published. ![google-cloud-pubsub-complete](https://tray.ai/documentation/images/connectors/service/google-cloud-pub-sub/5FlzQMoGRJlFnyPMijn37y_google-cloud-pubsub-complete.png) > **Info:** \*\*BEST PRACTICES: \*\*Whenever you do decide to create your own workflow, be sure to check out some of our key articles such as:- [Using callable workflows](https://tray.ai/documentation/platform/automation-integration/building-workflows/composable-workflows/calling-other-workflows) > - [Pagination](https://tray.ai/documentation/platform/automation-integration/advanced-use-cases/batching-queueing/pagination) > - [Data transformation guide](https://tray.ai/documentation/platform/automation-integration/building-workflows/mapping-data/data-transformation-guide)