fetch_test2.go

func TestConfiguration_FetchData(t *testing.T) {
	t.Run("errors when invalid api version", func(t *testing.T) {
		c := Configuration{
			baseURL:    "",
			apiVersion: 3,
			fetcher:    nil,
		}
		_, err := c.FetchData()
		assert.Error(t, ErrInvalidAPIVersion, err)
	})

	t.Run("errors when fetcher returns error", func(t *testing.T) {
		errFromFetcher := errors.New("mock error")
		mf := &mockFetcher{func(string) (io.ReadCloser, error) {
			return ioutil.NopCloser(bytes.NewBufferString("")), errFromFetcher
		}, 0}
		c := Configuration{
			baseURL:    "",
			apiVersion: 1,
			fetcher:    mf,
		}
		_, err := c.FetchData()
		assert.Error(t, errFromFetcher, err)
		assert.Equal(t, 1, mf.calls)
	})

	t.Run("decodes and maps from v1 response", func(t *testing.T) {
		mf := &mockFetcher{func(string) (io.ReadCloser, error) {
			return ioutil.NopCloser(bytes.NewBufferString(`
{"user_name":"test_user",
"dob":"1999-05-23T18:25:43.511Z",
"fav_sports":[{"name":"football","order":2},{"name":"hockey", "order":1}]}
					`)), nil
		}, 0}
		c := Configuration{
			baseURL:    "",
			apiVersion: 1,
			fetcher:    mf,
		}
		got, err := c.FetchData()
		assert.Nil(t, err)
		assert.Equal(t, 1, mf.calls)
		want := Person{
			Name:   "test_user",
			Age:    21,
			Sports: []string{"hockey", "football"},
		}
		assert.Equal(t, want, got)
	})

	t.Run("decodes and maps from v2 response", func(t *testing.T) {
		mf := &mockFetcher{func(string) (io.ReadCloser, error) {
			return ioutil.NopCloser(bytes.NewBufferString(`
{"name":"test_user",
"age":21,
"sports":["football","hockey"]}
					`)), nil
		}, 0}
		c := Configuration{
			baseURL:    "",
			apiVersion: 2,
			fetcher:    mf,
		}
		got, err := c.FetchData()
		assert.Nil(t, err)
		assert.Equal(t, 1, mf.calls)
		want := Person{
			Name:   "test_user",
			Age:    21,
			Sports: []string{"football", "hockey"},
		}
		assert.Equal(t, want, got)
	})
}