{
  "additionalProperties": false,
  "properties": {
    "upload_type": {
      "type": "string",
      "enum": [
        "avatar",
        "profile_background",
        "card_background",
        "custom_emoji",
        "composer"
      ]
    },
    "file_name": {
      "type": "string",
      "example": "IMG_2021.jpeg"
    },
    "file_size": {
      "type": "integer",
      "description": "File size should be represented in bytes.",
      "example": 4096
    },
    "metadata": {
      "type": "object",
      "additionalProperties": false,
      "properties": {
        "sha1-checksum": {
          "type": "string",
          "description": "The SHA1 checksum of the upload binary blob. Optionally be provided and serves as an additional security check when later processing the file in complete-external-upload endpoint."
        }
      }
    }
  },
  "required": [
    "upload_type",
    "file_name",
    "file_size"
  ]
}