@lafken/auth

@lafken/auth simplifies the creation and management of Amazon Cognito User Pools and User Pool Clients. It allows you to configure authentication flows, password policies, and standard attributes, as well as extend functionality using Lambda triggers through extensions.

Installation

npm install @lafken/auth

Configuration

Add the AuthResolver from the @lafken/auth/resolver library to your application configuration.

import { AuthResolver } from '@lafken/auth/resolver';

createApp({
  name: 'awesome-app',
  resolvers: [
    new AuthResolver({
      name: 'my-auth',
      userPool: {
        // ... user pool configuration
      },
      userClient: {
        // ... user client configuration
      }
    }),
  ],
  ...
});

Features

Configuring User Pool and Client

You can fully customize the User Pool and Client behaviors using userPool and userClient options.

new AuthResolver({
  name: 'customer-auth',
  userPool: {
    selfSignUpEnabled: true,
    signInAliases: { email: true },
    passwordPolicy: {
      minimumLength: 8,
      requireUppercase: true,
    },
  },
  userClient: {
    generateSecret: false,
    authFlow: ['ALLOW_USER_PASSWORD_AUTH', 'ALLOW_REFRESH_TOKEN_AUTH'],
  }
})

Extensions (Triggers)

@lafken/auth supports extending Cognito functionality using Lambda triggers. You can define "Extensions" which are classes decorated with @AuthExtension, containing methods decorated with @Trigger.

1. Define an Extension:

import { AuthExtension, Trigger } from '@lafken/auth';

@AuthExtension()
export class AuthTriggers {
  @Trigger({ type: 'preSignUp' })
  async preSignUp(event: any) {
    console.log('User is signing up:', event.userName);
    return event;
  }

  @Trigger({ type: 'postConfirmation' })
  async postConfirmation(event: any) {
    console.log('User confirmed:', event.userName);
    return event;
  }
}

2. Register the Extension:

Pass the extension class to the extensions property in AuthResolver.

new AuthResolver({
  name: 'app-auth',
  // ... other config
  extensions: [AuthTriggers],
})

Extending with Custom Logic

You can also use the extend callback to directly access the underlying CDK/Terraform resources (depending on the provider) or add custom resources related to the auth stack.

new AuthResolver({
  name: 'extended-auth',
  extend: ({ userPool, userPoolClient, scope }) => {
    // Access underlying constructs to add advanced configurations
    // or add related resources to the scope
  }
})