Using the UVCI

[jkiddo]

The UVCI is described as an identifer and its usage is stated in both the vaccine entry, test entry and recovery entry. However, in Annex 2, Option 2 the following is stated:

This single field serves as the unique identifier of the vaccination in the national vaccination registry of the corresponding country. It is the Member states’ responsibility to come up with the mechanism for generating and indexing the forementioned single unique vaccination identifiers.

I have a hard time seeing how the (national) vaccination registry should hold any identifiers in relation to an episode of obtained recovery.

Bottomline: The UVCI is by Annex 2 bound to the use of vaccine, but it is also used in the context of test and recovery

[jkiddo]

@dirkx - being a guy who knows a bit about legal stuff: Is it really allowed to have a reference to a specific vaccination event embodied in the DGC? Doesn't that make it a PII?

[martin-lindstrom]

Another question. When checking some of the data in https://github.com/eu-digital-green-certificates/dgc-testdata I notice that BG has a DGC with two different entries, both containing the same UVCI. My understanding is that this ID should identity the vaccination event, not the entire DGC.

[jkiddo]

Another question. When checking some of the data in https://github.com/eu-digital-green-certificates/dgc-testdata I notice that BG has a DGC with two different entries, both containing the same UVCI. My understanding is that this ID should identity the vaccination event, not the entire DGC.

Agree - this is also my understanding

[martin-lindstrom]

This needs to be sorted out. It is an issue when interop-testing - https://github.com/eu-digital-green-certificates/dgc-testdata/issues/66

@gabywh Could you shed some light on the issue?

[gabywh]

Bottomline: The UVCI is by Annex 2 bound to the use of vaccine, but it is also used in the context of test and recovery

Yes. It all started with vaccination. The name UVCI stuck. I did raise this as an issue but it will not be changed. HTH.

[martin-lindstrom]

@gabywh And your view on the use of the same UVCI for several entries? I claim that each ID should be unique per the event. But @SchulzeStTSI has another opinion (https://github.com/eu-digital-green-certificates/dgc-testdata/issues/66).

[gabywh]

Another question. When checking some of the data in https://github.com/eu-digital-green-certificates/dgc-testdata I notice that BG has a DGC with two different entries, both containing the same UVCI.

Then this is an error in the test. I created #59 and assigned to myself, in which I need to review all these no doubt well-intentioned bulk-submissions of test data and examples for both correctness and consistency.

My understanding is that this ID should identity the vaccination event, not the entire DGC. Correct. There is only a "certificate id" field per certificate type instance. The DGC "container" is simply that: a container, there is no medical event associated with it, but with the certificate(s) it contains

[gabywh]

@gabywh And your view on the use of the same UVCI for several entries?

This is incorrect. As above.

I claim that each ID should be unique per the event.

Correct.

[jkiddo]

Just so I can understand. Please express the desired behaviour in absolute terms

[gabywh]

Just so I can understand. Please express the desired behaviour in absolute terms

Not sure what you mean by "absolute terms" but here goes:

1. a certificate is issued for a medical event.
2. it will have a certificate id (the UVCI, which despite the V in the name is also same format for Test and Recovery, as above)
3. this certificate id is issued per medical event, thus unique to that medical event.
4. The DGC itself only has "root" properties of name + dob.

Did that help?

[SchulzeStTSI]

@gabywh The paper certificate is defined with one unique certificate identifier. Which ID of the multiple entries should then be the printed one? I think here is still the id in the root missing, next to the dob etc.

[MartinMitev]

As decided in the technical subgroup, we just support one event per certificate. So there is one event per certificate and one UVCI.

[gabywh]

As decided in the technical subgroup, we just support one event per certificate.

Yes, I know it was decided there, I'm in that subgroup ;) - and the statement is absolutely correct.

You cannot do anything other than support one event per certificate, that is already given by the medical workflow. There can only ever be one event per certificate by definition since one unique atomic medical event generates one unique certificate with its corresponding unique certificate id.

So there is one event per certificate and one UVCI.

Per certificate, yes.

However, the DGC Schema payload (and thus by extension the QR Code) can ('can' and not 'must') contain multiple certificates. Each certificate has its own certificate id in the UVCI format.

The DGC container (DGC.schema.json) is not a certificate in itself but may contain zero or more certificates (as defined in DGC.Types.schema.json). This specific entry in the FAQ may also help: https://github.com/ehn-digital-green-development/ehn-dgc-schema/wiki/FAQ#why-are-the-certificate-type-entries-specified-as-an-array

[chris2286266]

Can someone be so kind and verify the following UVCIs?

URN:UVCI:01:AT:10807843F94AEE0EE5093FBC254BD813#B URN:UVCI:01:AT:71EE2559DE38C6BF7304FB65A1A451EC#3 URN:UVCI:01:AT:B5921A35D6A0D696421B3E2462178297#I URN:UVCI:01:AT:858CC18CFCF5965EF82F60E493349AA5#K and URN:UVCI:01:AT:ABCDEFG988#/ URN:UVCI:01:AT:ABCDEFG997#:

Thanks

[gabywh]

one way amongst many using the examples/Luhn-Mod-N Python code (branch: next):

from luhn_mod_n import LuhnModN

UVCI = ["URN:UVCI:01:AT:10807843F94AEE0EE5093FBC254BD813#B",
        "URN:UVCI:01:AT:71EE2559DE38C6BF7304FB65A1A451EC#3",
        "URN:UVCI:01:AT:B5921A35D6A0D696421B3E2462178297#I",
        "URN:UVCI:01:AT:858CC18CFCF5965EF82F60E493349AA5#K",
        "URN:UVCI:01:AT:ABCDEFG988#/",
        "URN:UVCI:01:AT:ABCDEFG997#:"]

for uvci in UVCI:
    cert_id, _, check = uvci.rpartition('#')
    txt = cert_id + check
    is_valid = LuhnModN.validate_check_character(txt=txt)
    print(f"uvci '{cert_id}' with checksum '{check}' validates as: {is_valid}")