> ## Documentation Index
> Fetch the complete documentation index at: https://getconvoy.io/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Google PubSub

To ingest events using Google PubSub, follow the steps outlined below:

<Steps>
  <Step title="Create a PubSub Topic">
    <Frame>
      <img src="https://mintcdn.com/convoy/Ckv6F6QCAG1QB-UF/images/google-pubsub.png?fit=max&auto=format&n=Ckv6F6QCAG1QB-UF&q=85&s=02e88bcd6c317f243dc7ed02cfbd9377" alt="create google pubsub topic" width="1086" height="994" data-path="images/google-pubsub.png" />
    </Frame>
  </Step>

  <Step title="Create a Subscription">
    <Frame>
      <img src="https://mintcdn.com/convoy/Ckv6F6QCAG1QB-UF/images/create-google-subscription.png?fit=max&auto=format&n=Ckv6F6QCAG1QB-UF&q=85&s=0159c79579ad740674648afbee0f4232" alt="create a subscription" width="1178" height="1282" data-path="images/create-google-subscription.png" />
    </Frame>
  </Step>

  <Step title="Create a Service Account with PubSub Admin Role">
    <Frame>
      <img src="https://mintcdn.com/convoy/Ckv6F6QCAG1QB-UF/images/create-service-account.png?fit=max&auto=format&n=Ckv6F6QCAG1QB-UF&q=85&s=80b649980a90d48a543438e75a62aa2e" alt="create service account" width="1576" height="1292" data-path="images/create-service-account.png" />
    </Frame>
  </Step>

  <Step title="Generate Service Account JSON Key">
    <Frame>
      <img src="https://mintcdn.com/convoy/Ckv6F6QCAG1QB-UF/images/create-service-account-key.png?fit=max&auto=format&n=Ckv6F6QCAG1QB-UF&q=85&s=0d609c0e4f2907a67c21e01bc3ef6d3e" alt="generate service account json key" width="1164" height="760" data-path="images/create-service-account-key.png" />
    </Frame>
  </Step>

  <Step title="Configure Source">
    Supply your `Project ID`, `Topic Name`, `Subscription` and upload your service account json key.
  </Step>

  <Step title="Ingest Events">
    Continue to the next section to see how to format the event payload.
  </Step>
</Steps>

## Ingestion Options

There are two ways to ingest events into Convoy from Google PubSub:

* Format the payload using the structure below as a guide and write it to your topic.
  ```json5 reference payload theme={null}
   {
      "event_type": "string, required",
      "data": "object, required",
      "custom_headers": { // optional
          "x-convoy-message-type": "single",
          "sample-header": "sample-value"
      },
      "idempotency_key": "string, optional",
      "owner_id": "string, optional", // if included, the event is sent to all endpoints with the owner-id
      "endpoint_id": "string, optional" // if included, the event is sent to a single endpoint
   }
  ```
  > If `x-convoy-message-type` set to **broadcast**, the event will be sent to all endpoints in the project, ignoring both the `endpoint_id` and `owner_id` values.

For a full list of reference payloads, see [our guide on ingesting events](../../product-manual/events-and-event-deliveries#ingesting-events)

* Send your arbitrarily formatted event payloads to your topic and use Convoy’s transform functions to mutate them at the point of ingestion.
  ```js transform function theme={null}
  function transform(payload) {
      return {
          "endpoint_id": "",
          "owner_id": "",
          "event_type": "sample",
          "data": payload, // payload contains arbitrary message data read from your queue
          "custom_headers": {
              "sample-header": "sample-value"
          },
          "idempotency_key": ""
      }
  }
  ```

## Things to note

* Messages are read of the PubSub topic in chunks by each worker.
* Acknowledgements are done automatically, this is handled by Google's Go library.