User urn based on email should not be case-sensitive

Describe the bug A clear and concise description of what the bug is.

To Reproduce Steps to reproduce the behavior:

1. Go to datahub and have the identity provider create your user
2. Ingest some metadata into datahub using the CLI, but have username email in all caps
3. Observe you are not owner of the dataset you just ingested because it’s case-sensitive

Expected behavior II think [e-mail] and [e-mail] should be the same. In general, we should not allow usernames that only differ in the casing.

Possible solution Lower-case all usernames that are emails.

If user [e-mail] adds themselves as a dataset owner in an ingestion recipe, the dataset is not owned by them if their email in the identity provider is something like [e-mail] even though in terms of email address this is the same. I think in the case of users, the behavior should be to always lowercase, and we should not allow duplicate usernames in datahub which only differ by casing.

[iasoon]

I’m also running into this issue. My org doesn’t use a consistent casing for primary email identifiers in Azure AD, so it is not possible to transform ingested emails to the correct form without doing lookups. Being able to downcase usernames would solve this, either in all ingestion sources and identity providers, or as a setting in datahub itself. Alternatively, maybe we could have an option to use the ‘mail’ field that exists today in datahub as an identifier as well? In this case we’d know for sure that it’s an email and shouldn’t be case-sensitive.

[dingobar]

I don’t use DataHub anymore 😦 If anyone faces this issue I assume they will create their own ticket on the new issue tracker.