Export last user helper functions (setLastUserLoginId, removeLastUserLoginId, etc.)

[meirarmon]

Problem

The storeLastAuthenticatedUser feature stores the last authenticated user in localStorage, which is useful for pre-filling login forms. However, there's no way to programmatically set or clear this data from outside the SDK.

The helper functions exist internally in packages/sdks/web-js-sdk/src/enhancers/withLastLoggedInUser/helpers.ts:

• setLastUserLoginId(loginId: string)
• setLastUserDisplayName(displayName: string)
• removeLastUserLoginId()
• removeLastUserDisplayName()

But they are not exported from the package's public API.

Use Case

When a user authenticates through a separate flow (e.g., backoffice login, SSO redirect, or impersonation), the application needs to update the "last authenticated user" to reflect the new session. Without exported setters, the only workaround is to directly access the internal localStorage keys (dls_last_user_login_id, dls_last_user_display_name), which is fragile and could break if the keys change.

Proposed Solution

Export the existing helper functions from packages/sdks/web-js-sdk/src/index.ts, following the same pattern used for fingerprint helpers:

export {
  getLastUserLoginId,
  getLastUserDisplayName,
  setLastUserLoginId,
  setLastUserDisplayName,
  removeLastUserLoginId,
  removeLastUserDisplayName,
} from './enhancers/withLastLoggedInUser/helpers';

This is a minimal change since the functions already exist and are well-tested.

PR: #1332

Alternative Approach

Another approach would be to use cookies instead of localStorage, which would allow setting the last user from the server side. However, for simplicity we chose the localStorage export approach. If the Descope team prefers the cookie-based solution or has other suggestions, we're open to that as well.

[asafshen]

@meirarmon thanks for opening this issue, but I think there is a better way to have this without needing to interact with this

the Decsope component have form (and client) props - which can be used in flows for various of things (espeically for assiningn the email / loginId component

[meirarmon]

@meirarmon thanks for opening this issue, but I think there is a better way to have this without needing to interact with this

the Decsope component have form (and client) props - which can be used in flows for various of things (espeically for assiningn the email / loginId component

There needs to be a solution for when the SDK is used to finalize the login and not the frontent component

[meirarmon]

@asafshen I don't always want to go through the Descope login components. I think that giving your users a choice of how to consume your sdk, without limiting certain features to arbitrary implementation details would be a good thing.
In my codebase I created a file (included at the end) based on what I understood in the Descope sdk code. IMO exposing this functionality and ensuring that it does not break (right now my code became brittle because you don't export the logic that I need) would probably help more users than just me.

const STORAGE_KEY_LOGIN_ID = 'dls_last_user_login_id';
const STORAGE_KEY_DISPLAY_NAME = 'dls_last_user_display_name';
const STORAGE_KEY_LAST_AUTH = 'dls_last_auth';

interface LastAuthState {
  loginId: string;
  name: string;
  authMethod: string;
  oauthProvider: string;
  ssoTenantId: string;
  tenantId: string;
  ssoId: string;
}

const setLastUserLoginId = (loginId: string): void => {
  localStorage.setItem(STORAGE_KEY_LOGIN_ID, loginId);
};

const getLastUserLoginId = (): string | null => {
  return localStorage.getItem(STORAGE_KEY_LOGIN_ID);
};

const removeLastUserLoginId = (): void => {
  localStorage.removeItem(STORAGE_KEY_LOGIN_ID);
};

const setLastUserDisplayName = (displayName: string): void => {
  localStorage.setItem(STORAGE_KEY_DISPLAY_NAME, displayName);
};

const getLastUserDisplayName = (): string | null => {
  return localStorage.getItem(STORAGE_KEY_DISPLAY_NAME);
};

const removeLastUserDisplayName = (): void => {
  localStorage.removeItem(STORAGE_KEY_DISPLAY_NAME);
};

const setLastAuth = (lastAuth: LastAuthState): void => {
  localStorage.setItem(STORAGE_KEY_LAST_AUTH, JSON.stringify(lastAuth));
};

const getLastAuth = (): LastAuthState | undefined => {
  const value = localStorage.getItem(STORAGE_KEY_LAST_AUTH);
  if (!value) return undefined;
  try {
    return JSON.parse(value) as LastAuthState;
  } catch {
    return undefined;
  }
};

const removeLastAuth = (): void => {
  localStorage.removeItem(STORAGE_KEY_LAST_AUTH);
};

/** Convenience function to set all last user data (login ID, display name, and auth state) */
const setLastUser = (
  loginId: string,
  displayName?: string,
  authState?: Partial<Omit<LastAuthState, 'loginId'>>,
): void => {
  setLastUserLoginId(loginId);
  if (displayName) {
    setLastUserDisplayName(displayName);
  }
  if (authState) {
    setLastAuth({
      loginId,
      name: displayName ?? '',
      authMethod: authState.authMethod ?? '',
      oauthProvider: authState.oauthProvider ?? '',
      ssoTenantId: authState.ssoTenantId ?? '',
      tenantId: authState.tenantId ?? '',
      ssoId: authState.ssoId ?? '',
    });
  }
};

/** Convenience function to clear all last user data */
const clearLastUser = (): void => {
  removeLastUserLoginId();
  removeLastUserDisplayName();
  removeLastAuth();
};

export {
  clearLastUser,
  getLastAuth,
  getLastUserDisplayName,
  getLastUserLoginId,
  removeLastAuth,
  removeLastUserDisplayName,
  removeLastUserLoginId,
  setLastAuth,
  setLastUser,
  setLastUserDisplayName,
  setLastUserLoginId,
};

export type { LastAuthState };