Intercept APIs

Interceptors (similar to middleware) are a way to modify requests and responses. It is a middle man between your app and the network. They can be used for a variety of purposes such as logging, authentication, and caching.

The HttpAbstraction is made to work with interceptors out of the box. We have added a LoggingInterceptor that will log requests only during development. To activate an interceptor you can pass it in the interceptors parameter of the HttpAbstraction constructor.

1
HttpAbstraction(
2
  interceptors: [
3
    LoggingInterceptor(
4
      logBody: !kReleaseMode, // Only log bodies in debug mode
5
    ),
6
  ],
7
),

Create Your Own Interceptor

You can create your own interceptor by implementing the HttpInterceptor interface. This will have two methods: interceptRequest and interceptResponse.

The interceptRequest method will be called when a request is made. You can modify this request and return it to be used by the HttpAbstraction.

The interceptResponse method will be called when a response is received. You can modify this response and return to be used by the HttpAbstraction.

1
class MyCustomInterceptor implements HttpInterceptor {
2
  @override
3
  Future<http.BaseRequest> interceptRequest(http.BaseRequest request) async {
4
    // do something with the request, maybe refresh a token?
5
    return request;
6
  }
7

8
  @override
9
  Future<http.BaseResponse> interceptResponse(http.BaseResponse response) async {
10
    // do something with the response.
11
    return response;
12
  }
13
}