With the REST API component, you can send binary data as attachment. You just need to choose
multipart/form-data Content type and attachments from the input message will be
included to the request payload automatically.
REST API component automatically load binary data to attachments with next content types in response headers:
image/*text/csvapplication/mswordapplication/msexcgelapplication/pdfapplication/octet-streamapplication/x-binaryapplication/binaryapplication/macbinary