{
  "$id": "https://opendatafabric.org/schemas/datasets/v1alpha1/MetadataBlock",
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "description": "An individual block in the metadata chain that captures the history of modifications of a dataset.",
  "type": "object",
  "required": [
    "systemTime",
    "event",
    "sequenceNumber"
  ],
  "properties": {
    "systemTime": {
      "type": "string",
      "format": "date-time",
      "description": "System time when this block was written."
    },
    "prevBlockHash": {
      "type": "string",
      "format": "multihash",
      "description": "Hash sum of the preceding block."
    },
    "sequenceNumber": {
      "type": "integer",
      "format": "uint64",
      "description": "Block sequence number, starting from zero at the seed block."
    },
    "event": {
      "$ref": "https://opendatafabric.org/schemas/datasets/v1alpha1/MetadataEvent",
      "description": "Event data.",
      "unevaluatedProperties": false
    }
  }
}