Unhandled Rejection (TypeError): fsOpen is not a function about bbi-js

[cmdcolin]

Hi @lidaof

I am glad you are interested in this module! Sorry it is under-documented at the moment. The reason you saw this error is because it was trying to open your url as a "LocalFile" using nodejs functions, which don't exist in the webbrowser

I have published a new version of this module to npm that contains a "url" argument instead of "path" that can be used with remote url files

This module is under active development for use in JBrowse 2 and but I hope it can serve a function for you!

[lidaof]

Thank you so much for fast response @cmdcolin .
Do you think it will be easy to implement support of accept file Blob as input as well? since you can use web form to 'upload' a local bigwig file.

[cmdcolin]

Yes, that should be possible as well. Ideally concept of filehandles should ideally be abstracted into some module. Currently you could make a class that basically implemets a read method like this for the blob file object https://github.com/GMOD/bbi-js/blob/master/src/localFile.ts#L22-L37

This is done in the jbrowse source code using something like this https://github.com/GMOD/jbrowse/blob/master/src/JBrowse/Model/FileBlob.js

Ideally there would be a nice npm module for abstracting this...if you know of one let me know

[cmdcolin]

Then essentially you can pass your custom blob filehandle class with new BigWig({ filehandle: yourfilehandle_for_blob })

It should match the interface for this read function instead of the callback method from the FileBlob I listed https://github.com/GMOD/bbi-js/blob/master/src/localFile.ts#L22-L37

[lidaof]

Thank you @cmdcolin , the links are very helpful. I will do some tests my side see if I could figure it out.
Thanks again.

[cmdcolin]

Sounds good. If there is any new issue feel free to open a new thread

[cmdcolin]

@lidaof just FYI we are now making this module with common filehandles and it has a concept of a BlobFile https://www.npmjs.com/package/generic-filehandle !

[lidaof]

Hi @cmdcolin this is very good. Thank you for the hard work!