Read and validate Digital Corona Covid Certificate in Expo?

How to / Third Party Tooling
1

Hi all,

anyone got a a certificate reader (eudgc, eudcc) up and running in Expo? The QR code reader is the easy part (example with Webview), but so far I did not get any of the Github decoding examples to run within Expo Snack.

Mostly dependencies won’t load, won’t be found, they need need basic stuff like Buffer, crypto or BigInt. Below some examples. I already played around further, tried to replace some of the multiple decrypting libraries (base45, zlib, cbor), but did not succeed.

Any snack that works to decode and validate the certificates in Expo Snack?

Scopevisio/eudgc (Snack)
TypeError: undefined is not an object (evaluating ‘_eudgc.EuDgc.parse’)

FUUbi/digital-covid-certificate-lib (Snack)
ReferenceError: Can’t find variable: Buffer

miguelgrinberg/eudcc-decoder (Snack)
Cannot resolve module crypto after installing it as a dependency

VerHext/decode-dcc (Snack)
Unable to resolve module ‘module://zlib_bindings.js’

ministero-salute/dcc-utils (Snack)
Won’t even resolve dependencies

2

Is there a particular reason you want to use snack for this?

It looks like all of those require custom native code that won’t work in a snack. But you might be able to get them to work using EAS Build.

3

Good question. I am just used to developing my tiny apps within Expo Snack.

covidpass-org/covidpass (Snack) (Table-Snack)
Finally a working decoder

Next step is validation…

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