[msal-node] Confidential Client - Client Assertion implementation should accept callback instead of string argument

[KarishmaGhiya]

Core Library

MSAL Node (@azure/msal-node)

Wrapper Library

Not Applicable

Public or Confidential Client?

Confidential

Description

The client assertion implementation for confidential client should take a user callback that returns a string instead of accepting a string assertion. This will extend the usability of the API to allow users for refreshing the assertion token etc. .NET and Java implementation of MSAL already support this.

Source

Internal (Microsoft)

[KarishmaGhiya]

cc: @Robbie-Microsoft @bgavrilMS

[bgavrilMS]

Thanks, @KarishmaGhiya .

@Robbie-Microsoft - can you please propose an API here similar to what .NET has, something like WithClientAssertion(await GetAssertion()). The key point is that it needs to be async.

[Robbie-Microsoft]

@bgavrilMS sure. Before you left that comment, I made my own implementation. See my draft PR here. I didn't take async into account though.