Cognito Dart Auth SDK

Backend/admin AWS Cognito SDK for Dart.

This package is intended for server-side use where requests are signed for Amazon Cognito Identity Provider. The SDK exposes both direct request APIs and consumer/builder-style helpers through package:cognito_dart_auth_sdk/cognito_dart_auth_sdk.dart.

Installation

dependencies:
  cognito_dart_auth_sdk: ^0.0.3

Recommended Initialization Model

Use CognitoAuth (a public alias of Cognito) with:

1. an AWS region
2. a CognitoHttpClient implementation that signs requests for cognito-idp

If you already have request-sending and SigV4-signing logic, CognitoSigV4HttpClient can wrap it.

Preferred Backend Initialization

import 'package:cognito_dart_auth_sdk/cognito_dart_auth_sdk.dart';

Future<void> main() async {
  final httpClient = CognitoSigV4HttpClient(
    ({
      required Uri uri,
      required Map<String, String> headers,
      required String body,
      Duration? timeout,
    }) async {
      throw UnimplementedError('Provide your HTTP sender.');
    },
    ({
      required String region,
      required String service,
      required String method,
      required Uri uri,
      required Map<String, String> headers,
      required String body,
    }) async {
      throw UnimplementedError('Provide your SigV4 signer.');
    },
  );

  final auth = CognitoAuth(
    region: 'us-east-1',
    httpClient: httpClient,
  );

  await auth.adminCreateUser(
    userPoolId: 'us-east-1_example',
    username: 'alice@example.com',
  );
}

Common Backend Operations

Create or inspect a user

await auth.adminCreateUser(
  userPoolId: 'us-east-1_example',
  username: 'alice@example.com',
);

final user = await auth.adminGetUser(
  userPoolId: 'us-east-1_example',
  username: 'alice@example.com',
);

print(user);

Add custom attributes to a user pool

await auth.addCustomAttributes(
  userPoolId: 'us-east-1_example',
  customAttributes: [
    CognitoSchemaAttributeType(
      name: 'custom:department',
      attributeDataType: CognitoAttributeDataType.string,
    ),
  ],
);

Record adaptive-auth feedback

await auth.adminUpdateAuthEventFeedback(
  userPoolId: 'us-east-1_example',
  username: 'alice@example.com',
  eventId: 'event-id',
  feedbackValue: 'Valid',
);

Consumer/Builder APIs

Many operations are also exposed in consumer-style variants such as:

• adminCreateUserWith(...)
• adminRespondToAuthChallengeWith(...)
• adminUpdateAuthEventFeedbackWith(...)

Use those when you want builder validation or a more fluent payload setup.

Security Guidance

• Keep AWS credentials and SigV4 signing on the backend.
• Grant only the Cognito actions your service needs.
• Do not ship privileged signing logic or admin credentials in browser/mobile apps.
• Treat the sample apps as integration references, not as a secure admin deployment model.

Examples

See the example/ directory for current frontend sample apps and integration references.