Trigger for Object Storage that sends messages to WebSocket connections

A trigger for Object Storage sends messages to WebSocket connections when a specific event occurs with an Object Storage object. The trigger must be in the same cloud as the bucket whose events it is subscribed to.

A trigger for Object Storage requires a service account to send messages to WebSocket connections.

For more information about creating a trigger for Object Storage, see Creating a trigger for Object Storage that sends messages to WebSocket connections.

Events for setting up a triggerEvents for setting up a trigger

Events with bucket objects that can be tracked using a trigger:

• Creating an object.
• Editing an object ACL.
• Deleting an object.

Filtering events by objectFiltering events by object

Events are filtered using prefixes and suffixes for an object key.

• The prefix is a part at the beginning of the object key.
• The suffix is a part at the end of the object key.

Prefixes and suffixes can be of any length. When using a prefix and suffix at the same time, filtering is based on the logical AND: for the trigger to fire, the object key must match both the prefix and suffix.

Event batchingEvent batching

The grouping settings allow sending several events to WebSocket connections in one go. They set a top limit on event group size and on event group accumulation time. For example, if the event group size is 3, WebSocket connections can receive groups containing from 1 to 3 events.

Roles required for the proper operation of a trigger for Object StorageRoles required for the proper operation of a trigger for Object Storage

• To create a trigger, you need a permission for the service account under which the trigger runs the operation. This permission comes with the iam.serviceAccounts.user and editor roles or higher.
• For the trigger to fire, the service account needs the api-gateway.websocketBroadcaster role for the folder containing the API gateway.

Read more about access management.

Object Storage trigger message formatObject Storage trigger message format

After the trigger fires, it will send the following message to WebSocket connections:

{
  "messages": [
    {
      "event_metadata": {
        "event_id": "bb1dd06d-a82c-49b4-af98-d8e0********",
        "event_type": "yandex.cloud.events.storage.ObjectDelete",
        "created_at": "2019-12-19T14:17:47.847365Z",
        "tracing_context": {
          "trace_id": "dd52ace7********",
          "span_id": "",
          "parent_span_id": ""
        },
        "cloud_id": "b1gvlrnlei4l********",
        "folder_id": "b1g88tflru0e********"
      },
      "details": {
        "bucket_id": "s3-for-trigger",
        "object_id": "dev/0_15a775_972dbde4_orig12.jpg"
      }
    }
  ]
}

Useful linksUseful links

• Trigger for Object Storage that runs a Serverless Containers container
• Trigger for Object Storage that runs a Cloud Functions function