Buffer is undefined in the linear-view

[AcaDemIQ]

Hello,
I use JBrowse2 embedded version of the Linear View (v2.7.0)
And I've got this strange error:

ReferenceError: Buffer is not defined
    _fetchFromIndexEntry indexedFasta.ts:216
    getResiduesByName indexedFasta.ts:183
    getSequence indexedFasta.ts:193
    fill IndexedFastaAdapter.js:15
    fill AbortablePromiseCache.js:48
    get AbortablePromiseCache.js:135
    getFeatures IndexedFastaAdapter.js:73
    RxJS 22
    getFeatures FeatureRendererType.js:111
    render FeatureRendererType.js:133
    execute CoreRender.js:41
    call MainThreadRpcDriver.js:30

Can you help me with this problem?

Best regards, Aleksey.

[cmdcolin]

Hi there,
Generally a lot of our modules will require 'polyfilling' the Buffer module.

You can for example

npm install buffer

Then in your react code, maybe at app startup, write

import {Buffer} from 'buffer'
window.Buffer= buffer

There are also more 'automatic' ways to do this within the bundler system with e.g. the webpack NodePolyfillPlugin, but the above way is the easiest approach.

Example of NodePolyfillPlugin here https://github.com/GMOD/jbrowse-react-linear-genome-view-cra5-demo/blob/main/craco.config.js#L10-L12

Example of the window.Buffer=Buffer approach here https://github.com/GMOD/jbrowse-react-linear-genome-view-vite-demo/blob/main/src/main.tsx#L5-L7

Just curious, was this issue something new that happened when using v2.7.0?

[cmdcolin]

random side note: We may in the future try to make it so that we don't need the Buffer polyfill but it may take awhile as it is part of many of our data parsing packages

[AcaDemIQ]

Okey, I get it, close this ticket
Thanks a lot.