Sign-in with custom flow

? Do you want to use the default authentication and security configuration? Manual configuration?
    `Select the authentication/authorization services that you want to use: User Sign-Up, Sign-In, connected with AWS IAM controls (Enables per-user Storage features for images or other content, Analytics, and more)`
? Please provide a friendly name for your resource that will be used to label this category in the project:
    `<hit enter to take default or enter a custom label>`
? Please enter a name for your identity pool.
    `<hit enter to take default or enter a custom name>`
? Allow unauthenticated logins? (Provides scoped down permissions that you can control via AWS IAM)
    `No`
? Do you want to enable 3rd party authentication providers in your identity pool?
    `No`
? Please provide a name for your user pool:
    `<hit enter to take default or enter a custom name>`
? How do you want users to be able to sign in?
    `Username`
? Do you want to add User Pool Groups?
    `No`
? Do you want to add an admin queries API?
    `No`
? Multifactor authentication (MFA) user login options:
    `OFF`
? Email based user registration/forgot password:
    `Enabled (Requires per-user email entry at registration)`
? Please specify an email verification subject:
    `Your verification code`
? Please specify an email verification message:
    `Your verification code is {####}`
? Do you want to override the default password policy for this User Pool?
    `No`
? What attributes are required for signing up?
    `Email`
? Specify the app's refresh token expiration period (in days):
    `30`
? Do you want to specify the user attributes this app can read and write?
    `No`
? Do you want to enable any of the following capabilities?
    `NA`
? Do you want to use an OAuth flow?
    `No`
? Do you want to configure Lambda Triggers for Cognito?
    `Yes`
? Which triggers do you want to enable for Cognito?
    `Create Auth Challenge, Define Auth Challenge, Verify Auth Challenge Response`
? What functionality do you want to use for Create Auth Challenge?
    `Custom Auth Challenge Scaffolding (Creation)`
? What functionality do you want to use for Define Auth Challenge?
    `Custom Auth Challenge Scaffolding (Definition)`
? What functionality do you want to use for Verify Auth Challenge Response?
    `Custom Auth Challenge Scaffolding (Verification)`

? Do you want to edit your boilerplate-create-challenge function now?
    `Yes`
? Please edit the file in your editor: <local file path>/src/boilerplate-create-challenge.js

//crypto-secure-random-digit is used here to get random challenge code - https://github.com/ottokruse/crypto-secure-random-digit
const digitGenerator = require('crypto-secure-random-digit');

function sendChallengeCode(emailAddress, secretCode) {
  // Use SES or custom logic to send the secret code to the user.
}

function createAuthChallenge(event) {
  if (event.request.challengeName === 'CUSTOM_CHALLENGE') {
    // Generate a random code for the custom challenge
    const challengeCode = digitGenerator.randomDigits(6).join('');

    // Send the custom challenge to the user
    sendChallengeCode(event.request.userAttributes.email, challengeCode);

    event.response.privateChallengeParameters = {};
    event.response.privateChallengeParameters.answer = challengeCode;
  }
}

exports.handler = async (event) => {
  createAuthChallenge(event);
};

"dependencies": {
    "crypto-secure-random-digit": "^1.0.9"
}

? Press enter to continue
    `Hit Enter`

? Do you want to edit your boilerplate-define-challenge function now?
    `Yes`
? Please edit the file in your editor: <local file path>/src/boilerplate-define-challenge.js

exports.handler = async function (event) {
  if (
    event.request.session.length == 1 &&
    event.request.session[0].challengeName == 'SRP_A'
  ) {
    event.response.issueTokens = false;
    event.response.failAuthentication = false;
    event.response.challengeName = 'CUSTOM_CHALLENGE';
  } else if (
    event.request.session.length == 2 &&
    event.request.session[1].challengeName == 'CUSTOM_CHALLENGE' &&
    event.request.session[1].challengeResult == true
  ) {
    event.response.issueTokens = true;
    event.response.failAuthentication = false;
    event.response.challengeName = 'CUSTOM_CHALLENGE';
  } else {
    event.response.issueTokens = false;
    event.response.failAuthentication = true;
  }
};

? Press enter to continue
    `Hit Enter`

? Do you want to edit your boilerplate-verify function now?
    `Yes`
? Please edit the file in your editor: <local file path>/src/boilerplate-verify.js

function verifyAuthChallengeResponse(event) {
  if (
    event.request.privateChallengeParameters.answer ===
    event.request.challengeAnswer
  ) {
    event.response.answerCorrect = true;
  } else {
    event.response.answerCorrect = false;
  }
}

exports.handler = async (event) => {
  verifyAuthChallengeResponse(event);
};

? Press enter to continue
    `Hit Enter`

Confirm signUp succeeded

exports.handler = (event, context) => {
  if (event.request.session.length === 1 && 
    event.request.session[0].challengeName === 'SRP_A') {
    event.response.issueTokens = false;
    event.response.failAuthentication = false;
    event.response.challengeName = 'CUSTOM_CHALLENGE';
  } else if (
    event.request.session.length === 2 &&
    event.request.session[1].challengeName === 'CUSTOM_CHALLENGE' &&
    event.request.session[1].challengeResult === true
  ) {
    event.response.issueTokens = true;
    event.response.failAuthentication = false;
  } else {
    event.response.issueTokens = false;
    event.response.failAuthentication = true;
  }
  context.done(null, event);
};

Sign in succeeded