pass rejection reason to onDropRejected callback

Do you want to request a feature or report a bug?

• I found a bug
• I want to propose a feature

I’d like to get a reason for rejection in the onDropRejected callback currently I only get the file that was rejected. There was a request opened up previously #735, but it was closed. I am not sure why because the request was valid one and the response didn’t really help the reporter.

From what I can see there can be 3 reasons:

• you dragged multiple files to multiple={false} dropzone
• bad mime type
• file too big

Sure I can have a series of if statements in my callback to recognize what was the reason for rejection, but why do this work again when react-dropzone already done it?

Also it would be nice to have default error messages for those 3 scenarios, I’d propose:

• File ${file.name} is not supported
• Only accepts a single file
• File ${file.name} is ${bytes(file.size)}, the upper limit for file size is ${bytes(maxFileSize)}

[DominikSerafin]

Thanks for looking into it @rolandjitsu

Any implementation for this will be step forward in my opinion - but I have one suggestion - maybe it would be better to keep the error/validation as a string code that can be easily compared by a developer if he wants to show their own error messages?

I mean something like I’ve previously suggested: file-invalid-type, file-too-large, file-too-small, file-overflow/file-excessive, etc.

Or maybe even combined approach? Like this:

interface FileError extends Error {
  message: string; // e.g. 'File is larger than {maxSize}', 'File type does not meet {accept} criteria', etc.
  code: string; // e.g.  'file-too-large' 
  file: File;
}

[omcg33]

HEllo. Any news about PR?