MockHttpHandlers.md

Testing/Mocks: HTTP Handlers

Once registered, handlers continue to serve matching requests until canceled or until the transport mocks are reset/uninstalled.

Registering a handler to match requests by URI

The expected URI must match exactly, including scheme, host, path, and query.

MockTransports.http.when(
    Uri.parse('https://example.org/resource'),
    (FinalizedRequest request) async {
      if (request.method == 'GET') {
        return new MockResponse.ok(body: '...');
      }
      if (request.method == 'DELETE') {
        return new MockResponse(204);
      }
      ...
    });

Registering a handler to match requests by URI and method

MockTransports.http.when(
    Uri.parse('https://example.org/resource'),
    (FinalizedRequest request) async => new MockResponse.ok(body: '...'),
    method: 'GET');

Registering a handler to match requests by a URI pattern

Just like HTTP expectations, there is an alternate way to register handlers that allows matching via a Pattern for greater flexibility. This is especially useful for handlers since it essentially lets you define mock endpoints that can handle dynamic parameters in the path or query.

MockTransports.http.whenPattern(
    new RegExp('.*/notes/(\w+)$'),
    (FinalizedRequest request, Match match) async {
      var id = match.group(1);
      if (id == null) {
        // return all notes
      } else {
        // return note identified by the ID from the URI
      }
    });

Canceling a handler

Both when() and whenPattern() return a MockHttpHandler instance that can be used to cancel/unregister the handler.

var mockHandler = MockTransports.http.when(...);
...
mockHandler.cancel();