Export filterDefaultIdTokenClaims and update beforeSessionSaved docs

[frederikprijck]

📋 Changes

We have the following code here:

if (this.beforeSessionSaved) {
    const updatedSession = await this.beforeSessionSaved(
      session,
      oidcRes.id_token ?? null
    );
    session = {
      ...updatedSession,
      internal: session.internal
    };
  } else {
    session.user = filterClaims(idTokenClaims);
 }

What we can see here is that if the user does not pass a beforeSessionSaved handler, the session.user is set to a filtered list of claims to only contain the default tokens.

However, when a beforeSessionSaved handler is passed, the claims aren't filtered, and the session.user object passed to this.beforeSessionSaved has a non-filtered list of claims.

This means, that the following code would include all claims:

export const auth0 = new Auth0Client({
  async beforeSessionSaved(session, idToken) {
    return session
  },
})

However, this isn't clear from the docs. Additionally, if a user wants to only include a single claim, they currently need to ensure they provide all the default claims manually:

export const auth0 = new Auth0Client({
  async beforeSessionSaved(session, idToken) {
    return {
      ...session,
      user: {
        sub: session.user.sub,
        name: session.user.name,
        nickname: session.user.nickname,
        given_name: session.user.given_name,
        family_name: session.user.family_name,
        picture: session.user.picture,
        email: session.user.email,
        email_verified: session.user.email_verified,
        org_id: session.user.org_id,
        foo: session.user.foo, // add the foo claim
      },
    }
  },
})

This is way to complicated and not the kind of experience we want. Therefore this PR exports the filterClaims (and renames it to filterDefaultIdTokenClaims, so it can be used in custom beforeSessionSaved handlers accordingly.

📎 References

🎯 Testing

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 82.48%. Comparing base (7bd8398) to head (5dc224c).
Report is 3 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2119      +/-   ##
==========================================
+ Coverage   82.46%   82.48%   +0.02%     
==========================================
  Files          21       21              
  Lines        2024     2027       +3     
  Branches      355      356       +1     
==========================================
+ Hits         1669     1672       +3     
  Misses        348      348              
  Partials        7        7              

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[deepu105]

refactor fixes