Ionic 3 pdf rendering issue

I am working on an app using ionic 3 in which I am downloading a pdf file from server to local file directory in Ionic 3 (file.dataDirectory). I am trying to render the file to the screen using PDFJS library.
I am unable to render the page as I am getting the error:" fetch api cannot load url scheme “file” is not supported".
Please help me how to fetch the file from local file url and load in our app.