File input element

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Fields

Fields	Type	Description	Required?
type	String	The type of element. In this case type is always file_input.	Required
action_id	String	An identifier for the input value when the parent modal is submitted. You can use this when you receive a view_submission payload to identify the value of the input element. Should be unique among all other action_ids in the containing block. Maximum length is 255 characters.	Optional
filetypes	String[]	An array of valid file extensions that will be accepted for this element. All file extensions will be accepted if filetypes is not specified. This validation is provided for convenience only, and you should perform your own file type validation based on what you expect to receive.	Optional
max_files	Integer	Maximum number of files that can be uploaded for this file_input element. Minimum of 1, maximum of 10. Defaults to 10 if not specified.	Optional

Usage info

In order to use the file_input element within your app, your app must have the files:read scope. There is a 10MB file size limit.

Example

An input block containing a file_input input element.

{
  "type": "input",
  "block_id": "input_block_id",
  "label": {
    "type": "plain_text",
    "text": "Upload Files"
  },
  "element": {
    "type": "file_input",
    "action_id": "file_input_action_id_1",
    "filetypes": ["jpg", "png"],
    "max_files": 5,
  },
}