Add tests for mismatching accept headers

examples/handler_test.go

@@ -84,3 +84,19 @@ func TestExampleHandler_get_list(t *testing.T) {
 		t.Fatalf("Expected a status of %d, got %d", e, a)
 	}
 }
+
+func TestHttpErrorWhenHeaderDoesNotMatch(t *testing.T) {
+	r, err := http.NewRequest(http.MethodGet, "/blogs", nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	r.Header.Set(headerAccept, "application/xml")
+
+	rr := httptest.NewRecorder()
+	handler := &ExampleHandler{}
+	handler.ServeHTTP(rr, r)
+
+	if rr.Code != http.StatusUnsupportedMediaType {
+		t.Fatal("expected Unsupported Media Type staus error")
+	}
+}