Create a Strategy

Frontier provides a simple way to create a strategy. First of all you won't need to add frontier as a dependency to your project but instead you will use frontier_strategy as a dependency. To create a strategy you need to create a new class that extends Strategy and implement the authenticate method and the name getter. Below you can see an example of how to create a strategy:

dart

import 'package:frontier_strategy/frontier_strategy.dart';

class MyStrategy extends Strategy {

  MyStrategy(MyStrategyOptions options, StrategyCallback<MyStrategyOptions, Object> callback) : super(options, callback);

  @override
  String get name => 'MyStrategy';

  @override
  Future<void> authenticate(StrategyRequest request) async {
    callback(options, 'Hello World!', done);
  }
}

WARNING

Remember to call the callback function when you are done with the strategy execution. This will allow the user to use the strategy result to, for example, fetch the user data.

In the example above you can see that the MyStrategy class extends Strategy and implements the authenticate method and the name getter. The name getter is used to define the strategy name and the authenticate method is used to execute the strategy logic. The authenticate method receives a StrategyRequest instance with the request data and returns a Future. The result of the strategy must be passed to the callback function that is received in the constructor of the MyStrategy class.

The callback function is a function that receives the strategy options, the result of the strategy and a done function that you need to call when the execution of the strategy is done. Its type signature is StrategyCallback<T extends StrategyOptions, Object> which translates in:

dart


typedef StrategyCallback<T, I> = Future<void> Function(T strategyOptions, I? data, void Function(Object? result) done);

After creating the strategy you can use it in your project by following the Use a Strategy guide.

Create a Strategy ​

Create a Strategy