fix: set expires_in the proxy token response

[aramase]

Signed-off-by: Anish Ramasekar [email protected]

Reason for Change:

• msal-go returns AuthResult which doesn't contain the expires_in value. Computing that in the proxy based on current time and expires_on. This change is to make the response consistent with the IMDS response and also AAD response for token request.

This is the AAD response:

{
    "token_type": "Bearer",
    "expires_in": 86399,
    "ext_expires_in": 86399,
    "access_token": "<token>"
}

xref: https://learn.microsoft.com/en-us/azure/active-directory/develop/v2-oauth2-auth-code-flow#successful-response-2

Requirements

• squashed commits
• included documentation
• added unit tests and e2e tests (if applicable).

Issue Fixed:

fixes #624

Please answer the following questions with yes/no:

Does this change contain code from or inspired by another project? If so, did you notify the maintainers and provide attribution?

• yes
• no

Notes for Reviewers:
Opened AzureAD/microsoft-authentication-library-for-go#358 to request adding this as part of AuthResult, so we don't have to compute it.

[akshaysngupta]

Thanks! Is there a way to test this with the addon ?

[aramase]

Thanks! Is there a way to test this with the addon ?

Once this is merged, you can use the nightly image build from here in your pod spec by manually editing the pod. This will be part of next release (2 weeks from now) post which AKS will update the add-on to use the new release.