BE: can't inflate test data

[simonh1000]

Affected Country: BE

Issue Description

I am able to decode the data in my own QR Code (covidsafe app), but while the prefix data here can be base45 decoded, it cannot be Inflated, nor can it be converted into cbor.

Proposed Solution

[PeterEbraert]

Hello there,

Don't understand what the problem is... Can you get into contact with me on slack to elaborate on this?

Thanks,

Peter Ebraert (team BE)

[simonh1000]

Hi, I can't find a way to join Slack, so let me try to be clearer.

I'm trying to get the data from the QR Code.

My own certificate has content of HC1:.... If I pass it through a multi stage process of

• drop "HC1:" from front
• decode base45
• inflateZLib
• decode the binary cbor data

I get the expected json.

But with the test data, this pipeline fails. The base45 decode reports a success but the inflate fails, and just skipping the inflate is not a workaround.

So I am wondering whether the test data has constructed using some other sequence?

[krlnokrl]

Hello,

I believe there might be an issue with your implementation. Using the python trivial implementation the testdata decompresses fine. I have tested the string with a few implementations of zlib and they all pass.

The specification requires the use of zlib compression format. Gzip is not the same as Zlib.

	zlib	Gzip
Headers	0x78	1F8B

[simonh1000]

My mistake - it is inflateZLib that I am using, so that's not the error.

I'm doing this in Elm using https://package.elm-lang.org/packages/folkertdev/elm-tiny-inflate/latest/Inflate so there could be a bug there i guess

I'll play around some more

[daniel-eder]

@simonh1000 to join slack visit https://github.com/eu-digital-green-certificates/dgc-overview, the table contains an invite link

[simonh1000]

It's somewhere in my own base45 decoding - apologies