Changes in URL branching

[Jureamer]

• when both a custom policy and tenant name are present, handle the branching for assigning the token URL and authorize URL.

[Jureamer]

I have updated the code to support B2C login.
You can refer to the related documentation here: Request a Token.

While the existing README includes examples and references related to the custom_policy environment variable,
the implementation in the code was not fully accurate.

To support the URL change, the tenant_name environment variable is now also required.

It seems that the README may need to be updated accordingly. If you would like, I can make additional modifications to the documentation.

[pond]

@Jureamer

Sorry for the delay here. Just as I was getting around to this (a month late, sigh) some very valid points came up in #33 and I was thinking that this might all get folded into a V3.

OTOH, you might not want to take that leap, and might prefer this to go into V2 ASAP.

Any preference?

On the PR itself - code and test coverage all looks good and I can add a bit into README.md myself, or if you wanna throw it into this PR, be my guest. Either way, once the above is answered, I'd say we're good to merge.

[pond]

This will go into V3 under the rename omniauth-entra-id - to be released soon, I hope

[pond]

Thanks, merged. I think I see an error where if custom provider is given but tenant name isn't, it used to build an appropriate URL but your updated logic does not. Changed to:

EDIT - reverted - originally I said this:

base_url = if options.custom_policy && options.tenant_name
  "https://#{options.tenant_name}.b2clogin.com/#{options.tenant_name}.onmicrosoft.com/#{options.custom_policy}"
elsif options.custom_policy
  "#{options.base_azure_url}/#{options.tenant_id}/#{options.custom_policy}/#{oauth2}/token"
else
  "#{options.base_url}/#{options.tenant_id}"
end

EDIT: however I've read and re-read docs and searched extensively; it seems custom policies only are documented for the still-not-renamed Azure Active Directory B2C stuff, where a tenant name is also required. Entra doesn't seem to have that concept. Presumably, custom policy names wouldn't have worked if given in that use case, but wouldn't have been given anyway because they wouldn't have worked.

[Jureamer]

@pond
Sorry for the delayed response. First, thank you for reviewing and merging my work. If I have any further questions while using it, I'll raise them in the issue tracker. Thank you again.