Adds "Sign in with Google" as an additive auth path next to email and
password. When GOOGLE_CLIENT_ID and GOOGLE_CLIENT_SECRET are set, the
Google button appears on the sign-in page and the SSO settings page
shows an env-driven status panel. Access is restricted to Workspace
domains listed in GOOGLE_ALLOWED_DOMAINS (CSV); the hd claim is
re-verified server-side on every callback so a misconfigured Google
consent screen cannot bypass it.
New users from an allowed domain are JIT-provisioned in the default
account (oldest, or pinned via GOOGLE_DEFAULT_ACCOUNT_ID). Existing
users with a matching email get linked to their Google identity on
first sign-in; identity collisions (same email, different Google uid)
are rejected.
Google's MFA is trusted: users signed in via Google do not see the
WaboSign OTP prompt or the FORCE_MFA setup redirect. Password sign-in
keeps working unchanged, including its existing OTP gate.
Implementation:
- Devise gains :omniauthable when SSO is enabled; users get
provider/uid columns with a partial unique index that allows NULL
for password-only rows.
- Users::OmniauthCallbacksController handles /users/auth/google_oauth2/
callback, sets session[:bypass_otp_for_sso], and redirects on failure.
- SessionsController#destroy clears the bypass flag on sign-out.
- DashboardController#maybe_redirect_mfa_setup honours the flag and
User#signed_in_via_sso?.
- The previously empty _omniauthable.html.erb stub now renders the
Google button.
Request specs cover happy path, link-existing-user, domain rejection,
identity collision, and 2FA bypass.
GOOGLE_SSO.md is the operator-facing setup, behaviour, verification,
and troubleshooting guide. README links to it.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>