My team currently has a Component that implements <FileViewer> that works, but our tests warn us that:

console.log node_modules/react-file-viewer/dist/index.js:11
      Deprecated API usage: getDocument is called with pdfDataRangeTransport, passwordCallback or progressCallback argument

Would love to see this updated as react-file-viewer a good library.

Similar issue (but this appears to be a non-functioning component): #83

Relevant information on updating package:
mozilla/pdf.js#8538
mozilla/pdf.js@5135aa9#diff-dd42e9b2d2a652b8e312efa567698aa6

It appears the call to getDocument simply needs to be updated to the simplified parameters, with callbacks being set with onProgress, onPassword, etc.