public void WebMetricsHttpModule_WillRewriteBodyEndTag()
{
// arrange
var inputBuffer = Encoding.UTF8.GetBytes(
$"const foo = \"</body>\";</body>{Environment.NewLine}</html>");
var httpApplication = new HttpApplication();
var httpContext = TestHttpContextFactory.Create();
var httpModule = new WebMetricsHttpModule();
httpModule.Init(httpApplication);
var staticBindingFlags =
System.Reflection.BindingFlags.NonPublic |
System.Reflection.BindingFlags.Static;
var beginRequestKey = typeof(HttpApplication)
.GetField("EventBeginRequest", staticBindingFlags)
.GetValue(httpApplication);
var preRequestHandlerExecuteKey = typeof(HttpApplication)
.GetField("EventPreRequestHandlerExecute", staticBindingFlags)
.GetValue(httpApplication);
var postRequestHandlerExecuteKey = typeof(HttpApplication)
.GetField("EventPostRequestHandlerExecute", staticBindingFlags)
.GetValue(httpApplication);
var instanceBindingFlags =
System.Reflection.BindingFlags.NonPublic |
System.Reflection.BindingFlags.Instance;
var httpApplicationEvents = typeof(HttpApplication)
.GetProperty("Events", instanceBindingFlags)
.GetMethod
.Invoke(httpApplication, null)
as EventHandlerList;
var initResponseWriter = typeof(HttpResponse)
.GetMethod("InitResponseWriter", instanceBindingFlags);
var typeOfHttpResponseStreamFilterSink = typeof(HttpApplication)
.Assembly
.GetTypes()
.FirstOrDefault(e => e.FullName.StartsWith("System.Web.HttpResponseStreamFilterSink"));
var filteringField = typeOfHttpResponseStreamFilterSink
.GetField("_filtering", instanceBindingFlags);
initResponseWriter.Invoke(HttpContext.Current.Response, null);
var httpResponseStreamFilterSink = HttpContext.Current
.Response
.Filter;
// execute
httpApplicationEvents[beginRequestKey].DynamicInvoke(httpApplication, new EventArgs());
httpApplicationEvents[preRequestHandlerExecuteKey].DynamicInvoke(httpApplication, new EventArgs());
// swap in a stream we can observe
var actualStream = new MemoryStream();
typeof(HtmlRewriteFilterStream)
.GetField("_outputStream", instanceBindingFlags)
.SetValue(HttpContext.Current.Response.Filter, actualStream);
HttpContext.Current
.Response
.Filter
.Write(inputBuffer, 0, inputBuffer.Length);
filteringField.SetValue(
httpResponseStreamFilterSink,
true);
HttpContext.Current
.Response
.Filter
.Flush();
// verify
Assert.AreNotEqual(0, actualStream.Length);
var actualBuffer = new byte[actualStream.Length];
actualStream.Seek(0, SeekOrigin.Begin);
actualStream.Read(actualBuffer, 0, actualBuffer.Length);
var actualString = Encoding.UTF8.GetString(actualBuffer);
if (!actualString.Contains("x4d-webmetrics"))
{
Assert.Fail("The resulting string did not contain expected content.");
}
if (!actualString.Contains("\"</body>\""))
{
Assert.Fail("The resulting string did not contain expected quoted `</body>` text.");
}
}
public void WebMetricsHttpModule_WillNotRewriteUnsupportedContentType()
{
// arrange
var inputBuffer = Encoding.UTF8.GetBytes(
$"const foo = \"</body>\";</body>{Environment.NewLine}</html>");
var httpApplication = new HttpApplication();
var httpContext = TestHttpContextFactory.Create();
var httpModule = new WebMetricsHttpModule();
httpModule.Init(httpApplication);
var staticBindingFlags =
System.Reflection.BindingFlags.NonPublic |
System.Reflection.BindingFlags.Static;
var beginRequestKey = typeof(HttpApplication)
.GetField("EventBeginRequest", staticBindingFlags)
.GetValue(httpApplication);
var preRequestHandlerExecuteKey = typeof(HttpApplication)
.GetField("EventPreRequestHandlerExecute", staticBindingFlags)
.GetValue(httpApplication);
var postRequestHandlerExecuteKey = typeof(HttpApplication)
.GetField("EventPostRequestHandlerExecute", staticBindingFlags)
.GetValue(httpApplication);
var instanceBindingFlags =
System.Reflection.BindingFlags.NonPublic |
System.Reflection.BindingFlags.Instance;
var httpApplicationEvents = typeof(HttpApplication)
.GetProperty("Events", instanceBindingFlags)
.GetMethod
.Invoke(httpApplication, null)
as EventHandlerList;
var initResponseWriter = typeof(HttpResponse)
.GetMethod("InitResponseWriter", instanceBindingFlags);
var typeOfHttpResponseStreamFilterSink = typeof(HttpApplication)
.Assembly
.GetTypes()
.FirstOrDefault(e => e.FullName.StartsWith("System.Web.HttpResponseStreamFilterSink"));
var filteringField = typeOfHttpResponseStreamFilterSink
.GetField("_filtering", instanceBindingFlags);
initResponseWriter.Invoke(HttpContext.Current.Response, null);
var httpResponseStreamFilterSink = HttpContext.Current
.Response
.Filter;
// execute
httpApplicationEvents[beginRequestKey].DynamicInvoke(httpApplication, new EventArgs());
HttpContext.Current.Response.ContentType = "image/png";
httpApplicationEvents[preRequestHandlerExecuteKey].DynamicInvoke(httpApplication, new EventArgs());
// swap in a stream we can observe
var actualStream = new MemoryStream();
typeof(HtmlRewriteFilterStream)
.GetField("_outputStream", instanceBindingFlags)
.SetValue(HttpContext.Current.Response.Filter, actualStream);
HttpContext.Current
.Response
.Filter
.Write(inputBuffer, 0, inputBuffer.Length);
filteringField.SetValue(
httpResponseStreamFilterSink,
true);
HttpContext.Current
.Response
.Filter
.Flush();
// verify
var actualBuffer = new byte[actualStream.Length];
actualStream.Seek(0, SeekOrigin.Begin);
actualStream.Read(actualBuffer, 0, actualBuffer.Length);
var actualString = Encoding.UTF8.GetString(actualBuffer);
Assert.AreEqual(inputBuffer.Length, actualBuffer.Length);
for (int i = 0; i < actualBuffer.Length; i++)
{
if (inputBuffer[i] != actualBuffer[i])
{
Assert.Fail($"Data at buffer position {i} did not match, expected:<{inputBuffer[i]}>, actual:<{actualBuffer[i]}>.");
}
}
}