Auth.currentSession() returning 'No current User' intermittently

Describe the bug

Context: Angular.io application using cognito user pool and dynamodb.

Everything works find most of the time, and I cannot reproduce the error at will. However, other users are receiving errors in production and we’re capturing them through our implementation of rollbar.

We’ve tracked it down to the following code:

try {
  const cognitoUserSession: CognitoUserSession = await Auth.currentSession();
  const idToken = cognitoUserSession.getIdToken();
  return idToken.getJwtToken();
} catch (e) {
    // dump local storage for review
    const localStorage = window.localStorage;
    for (const key of Object.keys(localStorage)) {
      const value = localStorage[key].substring(0, 20);
      this.messageService.add(`${key} ${value}`);
    }
    throw new Error(`Auth.currentSession - Error ${e}`);
}

Intermittently Auth.currentSession() throws an error: ‘No current user’

I’ve reviewed the amplity-js code, for the error message. It seems to happen when the current user cannot be retrieved from the window.local storage.

/** * Get current authenticated user * @return - A promise resolves to current authenticated CognitoUser if success */ public currentUserPoolUser(params?: CurrentUserOpts): Promise<CognitoUser | any> { if (!this.userPool) { return this.rejectNoUserPool(); } const that = this; return new Promise((res, rej) => { this._storageSync.then(() => { const user = that.userPool.getCurrentUser(); if (!user) { logger.debug(‘Failed to get user from user pool’); rej(‘No current user’); return; }

            // refresh the session if the session expired.
            user.getSession((err, session) => {
                if (err) {
                    logger.debug('Failed to get the user session', err);
                    rej(err);
                    return;
                }

However, in my error handler I’ve logged the key pairs in local storage and they exist.

I’m looking for any help as to what might be causing this. Thanks again for you help.

Desktop (please complete the following information):

• OS: Windows
• Browser chrome
• Version 76

You can turn on the debug mode to provide more info for us by setting window.LOG_LEVEL = ‘DEBUG’; in your app.