golang httpmock augmented with assertions

mock.go

import (
	"testing"

	"github.com/jarcoal/httpmock"
	"net/http"
	"io/ioutil"
)

type Call struct {
	req  *http.Request
	resp *http.Response
}

type MockEndpoint struct {
	responder httpmock.Responder
	Calls     []Call
}

func NewMockEndpoint(wrappedResponder httpmock.Responder) MockEndpoint {
	mock := MockEndpoint{
		responder: wrappedResponder,
		Calls:     []Call{},
	}

	return mock
}

func (r *MockEndpoint) GetResponder() httpmock.Responder {
	return func(req *http.Request) (resp *http.Response, err error) {

		resp, err = r.responder(req)

		r.Calls = append(r.Calls, Call{req: req, resp: resp})

		return
	}
}

func (r MockEndpoint) AssertCalled() bool {
	return len(r.Calls) > 0
}

func (r MockEndpoint) AssertCalledWithBody(body string) bool {
	for _, call := range r.Calls {
		b, err := ioutil.ReadAll(call.req.Body)

		if err != nil {
			continue
		}

		if string(b) == body {
			return true
		}
	}

	return false
}

func (r MockEndpoint) AssertCalledWithQueryParam(key string, value string) bool {
	for _, call := range r.Calls {

		if call.req.URL.Query().Get(key) == value {
			return true
		}
	}

	return false
}

func (r MockEndpoint) AssertCalledOnce() bool {
	return r.AssertCallCount(1)
}

func (r MockEndpoint) AssertCallCount(count int) bool {
	return r.CallCount() == count
}

func (r MockEndpoint) CallCount() int {
	return len(r.Calls)
}

var baseURL = "..."

func TestFoo(t *testing.T) {
  httpmock.Activate()
  defer httpmock.Deactivate()
  
  mock := NewMockEndpoint(httpmock.NewStringResponder(200, "bar"))
	httpmock.RegisterResponder(
		"GET",
		baseURL + "/foo",
		mock.GetResponder(),
	)
	
	// do something which invokes the /foo endpoint
	
	// Assertions:
	if !mock.AssertCalled() {
	  t.Errorf("/foo not called")
	 }
}