Validation of file types

[Nnachevvv]

Closes #515

This PR provides mechanism to validate the file type uploaded to the backend. I added two types of validation , since using only the extension is not secure enough. Now we will support the following extension and mime types:

  const allowedExtensions = /txt|json|jpeg|jpg|png|xml|xlsx|xls|docx/
  const mimeAllowlist = [
    'text/plain',
    'application/json',
    'application/pdf',
    'image/png',
    'image/jpeg',
    'application/xml',
    'text/xml',
    'application/msword',
    'application/vnd.ms-excel',
    'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet',
  ]

Motivation and context

Testing

Tried to upload one valid and invalid file:

Failed with:

Allowed mime type and not allowed extension:

[github-actions]

✅ Tests will run for this PR. Once they succeed it can be merged.

[igoychev]

let's add a pdf as allowed too

[Nnachevvv]

Added

[igoychev]

Looks great!