Azure AAD B2C: manage different datetime formats on custom claims

Stefano Sapienti 65

Hi, I created a custom signup-signin policy in Azure B2C that asks the user for birth date. I store the date in a custom attribute named extension_birthday of type string.
We decided to use DateTimeDropdown as UserInputType and we found that if DataType of the claim is not "date" we receive an error creating final JWT, dunno why, if you have an idea it would be appreciated. Btw, the main problem is that we are integrating with a third party openid provider that returns birth date in DD/MM/YYYY format so, when we receive the JWT B2C raise the following error: "The date "24/2/1991" being used to initialize the instance is not in a recognized format." How it is supposed to handle this scenario? Is it possible to convert dates between different formats? Thanks in advance for the help.

JamesTran-MSFT 36,541 Reputation points Microsoft Employee

2023-04-21T17:13:38.1+00:00
@Stefano Sapienti

Thank you for your post and I apologize for the delayed response!

Error Message: The date "24/2/1991" being used to initialize the instance is not in a recognized format.

My teammate is currently looking into your issue but in the meantime can you share any documentation that you followed in order to set up your Birth Date custom policy?

Additional Links:

Date claims transformations

Convert DateTime claim to string in Azure AD B2C custom policy

DateTimeComparison

AssertBooleanClaimIsEqualToValue

If you have any other questions, please let me know. Thank you for your time and patience throughout this issue.
Stefano Sapienti 65 Reputation points

2023-04-27T13:29:32.31+00:00

Hi @JamesTran-MSFT thanks for answering.

The birth date was previously implemented like a simple extension attribute https://learn.microsoft.com/en-us/azure/active-directory-b2c/user-flow-custom-attributes?pivots=b2c-custom-policy#create-a-custom-attribute-through-azure-portal

It was entered by the end user that could insert the date in different format based on his location. Mainly dd/mm/yyyy or mm/dd/yyyy

Now we decided to use the standard dropdown date picker https://learn.microsoft.com/en-us/azure/active-directory-b2c/claimsschema#datetimedropdown without defining a new extension attribute but by re-using the old one.

When we load data from AD we receive an error if the stored date is in dd/mm/yyyy format. otherwise is converted in yyyy-mm-dd correctly and everything works fine.

If we set the ClaimType DataType to string instead of date we do not have the conversion error but we receive an error (Microsoft.Cpim.Common.CpimException) creating final JWT even if the entered date is correct.

Hope this helps clarifying the problem. Thanks in advance.

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Azure AAD B2C: manage different datetime formats on custom claims