json_schema: {
      "$schema": "http://json-schema.org/draft-04/schema#",
      "title": "CAP Files Schema v1.0.0",
      "type": "object",
      "properties": {
          "_buckets": {
              "type": "object",
              "properties": {
                  "record": {
                      "type": "string",
                      "description": "Record bucket ID."
                  },
                  "deposit": {
                      "type": "string",
                      "description": "Deposit bucket ID."
                  }
              }
          },
          "_files": {
              "items": {
                  "type": "object",
                  "description": "Describe information needed for files in records.",
                  "properties": {
                      "checksum": {
                          "type": "string"
                      },
                      "bucket": {
                          "type": "string"
                      },
                      "version_id": {
                          "type": "string"
                      },
                      "key": {
                          "type": "string"
                      },
                      "type": {
                          "type": "string",
                          "description": "File type extension."
                      },
                      "size": {
                          "type": "integer"
                      }
                  }
              },
              "type": "array"
          }
      }
  }