How to allow my user to reset their password on Cognito User Pools?

Resetting the password with forgot password flow has two steps:

1. Start the process by requesting for a verification code from the service. A code will be delivered to the user's phone/email.
2. Set the new password using the delivered verification code.

Use these two functions to perform the above steps and reset the password:

1. cognitoUser.forgotPassword(): This will start the forgot password process flow. The service generates a verification code and sends it to the user. The "data", returned through callback.inputVerificationCode(data), indicates where the verification code was sent.

2. cognitoUser.confirmPassword(): Use the delivered verification code with this function to set a new password.

AWS' docs are terrible on this topic (Cognito). You basically need to setup cognitoUser, then call forgotPassword

export function resetPassword(username) {
    // const poolData = { UserPoolId: xxxx, ClientId: xxxx };
    // userPool is const userPool = new AWSCognito.CognitoUserPool(poolData);

    // setup cognitoUser first
    cognitoUser = new AWSCognito.CognitoUser({
        Username: username,
        Pool: userPool
    });

    // call forgotPassword on cognitoUser
    cognitoUser.forgotPassword({
        onSuccess: function(result) {
            console.log('call result: ' + result);
        },
        onFailure: function(err) {
            alert(err);
        },
        inputVerificationCode() { // this is optional, and likely won't be implemented as in AWS's example (i.e, prompt to get info)
            var verificationCode = prompt('Please input verification code ', '');
            var newPassword = prompt('Enter new password ', '');
            cognitoUser.confirmPassword(verificationCode, newPassword, this);
        }
    });
}

// confirmPassword can be separately built out as follows...  
export function confirmPassword(username, verificationCode, newPassword) {
    cognitoUser = new AWSCognito.CognitoUser({
        Username: username,
        Pool: userPool
    });

    return new Promise((resolve, reject) => {
        cognitoUser.confirmPassword(verificationCode, newPassword, {
            onFailure(err) {
                reject(err);
            },
            onSuccess() {
                resolve();
            },
        });
    });
}