Request Results Management in Flutter

This project introduces a custom solution for efficiently handling request results in Flutter applications. Leveraging the Either abstraction, the system elegantly manages both success and failure scenarios, allowing for detailed handling of each case. Additionally, it includes a robust global error management system to ensure a seamless user experience without interruptions.

Requests

Defining URLs

In ApiService, define the base URLs that will be used, using http in the same scheme as http:

class ApiService {
  static ApiMethods get http => ApiMethods(
        baseUrl: Urls.httpUrl,
      );
}

Creating an Instance for Requests

Create an instance of ApiService calling the get method on the base URL of the requests:

static final _api = ApiService.http;

HTTP Requests

To make requests, call the corresponding HTTP method as shown below:

final result = await _api.get('[path]');

If there is a header:

final result = await _api.get(
  '[path]',
  headers: <String, dynamic>{},
);

When there is a body:

final result = await _api.post(
  '[path]',
  headers: <String, dynamic>{},
  data: <String, dynamic>{},
);

Handling Results

The result of the requests will be an instance of Either, which can be either a success or a failure. To handle the result, access the handle method, passing a function to obtain the current context, what to do when a success occurs, and what to do when a failure occurs:

result.handle(
  getContext: _getContext,
  success: (value) {},
  failure: (type, message, handleError) {},
);

When a failure occurs and you want the default handling to be performed, call the handleError function:

result.handle(
  getContext: _getContext,
  success: (value) {},
  failure: (type, message, handleError) {
    handleError();
  },
);

The default handling will only be applied when handleError is called, allowing for local handling as follows:

result.handle(
  getContext: _getContext,
  success: (value) {},
  failure: (type, message, handleError) {
    switch (type) {
      case FailureType.badGateway:
        // Local Error Handling
      default:
        handleError();
    }
  },
);